TY  - JOUR
A1  - Aliu, E.
A1  - Archambault, S.
A1  - Arlen, T.
A1  - Aune, T.
A1  - Beilicke, M.
A1  - Benbow, W.
A1  - Boettcher, Markus
A1  - Bouvier, A.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Cesarini, A.
A1  - Ciupik, L.
A1  - Collins-Hughes, E.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Dickherber, R.
A1  - Duke, C.
A1  - Dumm, J.
A1  - Errando, M.
A1  - Falcone, A.
A1  - Federici, Simone
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Finnegan, G.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Galante, N.
A1  - Gall, D.
A1  - Godambe, S.
A1  - Griffin, S.
A1  - Grube, J.
A1  - Gyuk, G.
A1  - Hanna, D.
A1  - Holder, J.
A1  - Huan, H.
A1  - Kaaret, P.
A1  - Karlsson, N.
A1  - Khassen, Y.
A1  - Kieda, D.
A1  - Krawczynski, H.
A1  - Krennrich, F.
A1  - Lee, K.
A1  - Madhavan, A. S.
A1  - Maier, G.
A1  - Majumdar, P.
A1  - McArthur, S.
A1  - McCann, A.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nelson, T.
A1  - de Bhroithe, A. O'Faolain
A1  - Ong, R. A.
A1  - Orr, M.
A1  - Otte, A. N.
A1  - Park, N.
A1  - Perkins, J. S.
A1  - Pichel, A.
A1  - Pohl, Martin
A1  - Prokoph, H.
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reyes, L. C.
A1  - Reynolds, P. T.
A1  - Roache, E.
A1  - Saxon, D. B.
A1  - Sembroski, G. H.
A1  - Staszak, D.
A1  - Telezhinsky, Igor O.
A1  - Tesic, G.
A1  - Theiling, M.
A1  - Thibadeau, S.
A1  - Tsurusaki, K.
A1  - Varlotta, A.
A1  - Vassiliev, V. V.
A1  - Vincent, S.
A1  - Vivier, M.
A1  - Wakely, S. P.
A1  - Weekes, T. C.
A1  - Weinstein, A.
A1  - Welsing, R.
A1  - Williams, D. A.
A1  - Zitzer, B.
A1  - Fortin, P.
A1  - Horan, D.
A1  - Fumagalli, M.
A1  - Kaplan, K.
A1  - Prochaska, J. X.
T1  - Veritas observations of six bright, hard-spectrum fermi-lat blazars
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - We report on VERITAS very high energy (VHE; E >= 100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band, taking gamma-ray absorption by the extragalactic background light into account. This allowed the selection of six bright, hard-spectrum blazars that were good candidate TeV emitters. Spectroscopic redshift measurements were attempted with the Keck Telescope for the targets without Sloan Digital Sky Survey spectroscopic data. No VHE emission is detected during the observations of the six sources described here. Corresponding TeV upper limits are presented, along with contemporaneous Fermi observations and non-concurrent Swift UVOT and X-Ray Telescope data. The blazar broadband spectral energy distributions (SEDs) are assembled and modeled with a single-zone synchrotron self-Compton model. The SED built for each of the six blazars shows a synchrotron peak bordering between the intermediate-and high-spectrum-peak classifications, with four of the six resulting in particle-dominated emission regions.
KW  - BL Lacertae objects: general
KW  - gamma rays: galaxies
Y1  - 2012
U6  - https://doi.org/10.1088/0004-637X/759/2/102
SN  - 0004-637X
VL  - 759
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Middeldorp, Christel M.
A1  - Mahajan, Anubha
A1  - Horikoshi, Momoko
A1  - Robertson, Neil R.
A1  - Beaumont, Robin N.
A1  - Bradfield, Jonathan P.
A1  - Bustamante, Mariona
A1  - Cousminer, Diana L.
A1  - Day, Felix R.
A1  - De Silva, N. Maneka
A1  - Guxens, Monica
A1  - Mook-Kanamori, Dennis O.
A1  - St Pourcain, Beate
A1  - Warrington, Nicole M.
A1  - Adair, Linda S.
A1  - Ahlqvist, Emma
A1  - Ahluwalia, Tarunveer Singh
A1  - Almgren, Peter
A1  - Ang, Wei
A1  - Atalay, Mustafa
A1  - Auvinen, Juha
A1  - Bartels, Meike
A1  - Beckmann, Jacques S.
A1  - Bilbao, Jose Ramon
A1  - Bond, Tom
A1  - Borja, Judith B.
A1  - Cavadino, Alana
A1  - Charoen, Pimphen
A1  - Chen, Zhanghua
A1  - Coin, Lachlan
A1  - Cooper, Cyrus
A1  - Curtin, John A.
A1  - Custovic, Adnan
A1  - Das, Shikta
A1  - Davies, Gareth E.
A1  - Dedoussis, George V.
A1  - Duijts, Liesbeth
A1  - Eastwood, Peter R.
A1  - Eliasen, Anders U.
A1  - Elliott, Paul
A1  - Eriksson, Johan G.
A1  - Estivill, Xavier
A1  - Fadista, Joao
A1  - Fedko, Iryna O.
A1  - Frayling, Timothy M.
A1  - Gaillard, Romy
A1  - Gauderman, W. James
A1  - Geller, Frank
A1  - Gilliland, Frank
A1  - Gilsanz, Vincente
A1  - Granell, Raquel
A1  - Grarup, Niels
A1  - Groop, Leif
A1  - Hadley, Dexter
A1  - Hakonarson, Hakon
A1  - Hansen, Torben
A1  - Hartman, Catharina A.
A1  - Hattersley, Andrew T.
A1  - Hayes, M. Geoffrey
A1  - Hebebrand, Johannes
A1  - Heinrich, Joachim
A1  - Helgeland, Oyvind
A1  - Henders, Anjali K.
A1  - Henderson, John
A1  - Henriksen, Tine B.
A1  - Hirschhorn, Joel N.
A1  - Hivert, Marie-France
A1  - Hocher, Berthold
A1  - Holloway, John W.
A1  - Holt, Patrick
A1  - Hottenga, Jouke-Jan
A1  - Hypponen, Elina
A1  - Iniguez, Carmen
A1  - Johansson, Stefan
A1  - Jugessur, Astanand
A1  - Kahonen, Mika
A1  - Kalkwarf, Heidi J.
A1  - Kaprio, Jaakko
A1  - Karhunen, Ville
A1  - Kemp, John P.
A1  - Kerkhof, Marjan
A1  - Koppelman, Gerard H.
A1  - Korner, Antje
A1  - Kotecha, Sailesh
A1  - Kreiner-Moller, Eskil
A1  - Kulohoma, Benard
A1  - Kumar, Ashish
A1  - Kutalik, Zoltan
A1  - Lahti, Jari
A1  - Lappe, Joan M.
A1  - Larsson, Henrik
A1  - Lehtimaki, Terho
A1  - Lewin, Alexandra M.
A1  - Li, Jin
A1  - Lichtenstein, Paul
A1  - Lindgren, Cecilia M.
A1  - Lindi, Virpi
A1  - Linneberg, Allan
A1  - Liu, Xueping
A1  - Liu, Jun
A1  - Lowe, William L.
A1  - Lundstrom, Sebastian
A1  - Lyytikainen, Leo-Pekka
A1  - Ma, Ronald C. W.
A1  - Mace, Aurelien
A1  - Magi, Reedik
A1  - Magnus, Per
A1  - Mamun, Abdullah A.
A1  - Mannikko, Minna
A1  - Martin, Nicholas G.
A1  - Mbarek, Hamdi
A1  - McCarthy, Nina S.
A1  - Medland, Sarah E.
A1  - Melbye, Mads
A1  - Melen, Erik
A1  - Mohlke, Karen L.
A1  - Monnereau, Claire
A1  - Morgen, Camilla S.
A1  - Morris, Andrew P.
A1  - Murray, Jeffrey C.
A1  - Myhre, Ronny
A1  - Najman, Jackob M.
A1  - Nivard, Michel G.
A1  - Nohr, Ellen A.
A1  - Nolte, Ilja M.
A1  - Ntalla, Ioanna
A1  - Oberfield, Sharon E.
A1  - Oken, Emily
A1  - Oldehinkel, Albertine J.
A1  - Pahkala, Katja
A1  - Palviainen, Teemu
A1  - Panoutsopoulou, Kalliope
A1  - Pedersen, Oluf
A1  - Pennell, Craig E.
A1  - Pershagen, Goran
A1  - Pitkanen, Niina
A1  - Plomin, Robert
A1  - Power, Christine
A1  - Prasad, Rashmi B.
A1  - Prokopenko, Inga
A1  - Pulkkinen, Lea
A1  - Raikkonen, Katri
A1  - Raitakari, Olli T.
A1  - Reynolds, Rebecca M.
A1  - Richmond, Rebecca C.
A1  - Rivadeneira, Fernando
A1  - Rodriguez, Alina
A1  - Rose, Richard J.
A1  - Salem, Rany
A1  - Santa-Marina, Loreto
A1  - Saw, Seang-Mei
A1  - Schnurr, Theresia M.
A1  - Scott, James G.
A1  - Selzam, Saskia
A1  - Shepherd, John A.
A1  - Simpson, Angela
A1  - Skotte, Line
A1  - Sleiman, Patrick M. A.
A1  - Snieder, Harold
A1  - Sorensen, Thorkild I. A.
A1  - Standl, Marie
A1  - Steegers, Eric A. P.
A1  - Strachan, David P.
A1  - Straker, Leon
A1  - Strandberg, Timo
A1  - Taylor, Michelle
A1  - Teo, Yik-Ying
A1  - Thiering, Elisabeth
A1  - Torrent, Maties
A1  - Tyrrell, Jessica
A1  - Uitterlinden, Andre G.
A1  - van Beijsterveldt, Toos
A1  - van der Most, Peter J.
A1  - van Duijn, Cornelia M.
A1  - Viikari, Jorma
A1  - Vilor-Tejedor, Natalia
A1  - Vogelezang, Suzanne
A1  - Vonk, Judith M.
A1  - Vrijkotte, Tanja G. M.
A1  - Vuoksimaa, Eero
A1  - Wang, Carol A.
A1  - Watkins, William J.
A1  - Wichmann, H-Erich
A1  - Willemsen, Gonneke
A1  - Williams, Gail M.
A1  - Wilson, James F.
A1  - Wray, Naomi R.
A1  - Xu, Shujing
A1  - Xu, Cheng-Jian
A1  - Yaghootkar, Hanieh
A1  - Yi, Lu
A1  - Zafarmand, Mohammad Hadi
A1  - Zeggini, Eleftheria
A1  - Zemel, Babette S.
A1  - Hinney, Anke
A1  - Lakka, Timo A.
A1  - Whitehouse, Andrew J. O.
A1  - Sunyer, Jordi
A1  - Widen, Elisabeth E.
A1  - Feenstra, Bjarke
A1  - Sebert, Sylvain
A1  - Jacobsson, Bo
A1  - Njolstad, Pal R.
A1  - Stoltenberg, Camilla
A1  - Smith, George Davey
A1  - Lawlor, Debbie A.
A1  - Paternoster, Lavinia
A1  - Timpson, Nicholas J.
A1  - Ong, Ken K.
A1  - Bisgaard, Hans
A1  - Bonnelykke, Klaus
A1  - Jaddoe, Vincent W. V.
A1  - Tiemeier, Henning
A1  - Jarvelin, Marjo-Riitta
A1  - Evans, David M.
A1  - Perry, John R. B.
A1  - Grant, Struan F. A.
A1  - Boomsma, Dorret I.
A1  - Freathy, Rachel M.
A1  - McCarthy, Mark I.
A1  - Felix, Janine F.
T1  - The Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia
BT  - design, results and future prospects
JF  - European journal of epidemiology
N2  - The impact of many unfavorable childhood traits or diseases, such as low birth weight and mental disorders, is not limited to childhood and adolescence, as they are also associated with poor outcomes in adulthood, such as cardiovascular disease. Insight into the genetic etiology of childhood and adolescent traits and disorders may therefore provide new perspectives, not only on how to improve wellbeing during childhood, but also how to prevent later adverse outcomes. To achieve the sample sizes required for genetic research, the Early Growth Genetics (EGG) and EArly Genetics and Lifecourse Epidemiology (EAGLE) consortia were established. The majority of the participating cohorts are longitudinal population-based samples, but other cohorts with data on early childhood phenotypes are also involved. Cohorts often have a broad focus and collect(ed) data on various somatic and psychiatric traits as well as environmental factors. Genetic variants have been successfully identified for multiple traits, for example, birth weight, atopic dermatitis, childhood BMI, allergic sensitization, and pubertal growth. Furthermore, the results have shown that genetic factors also partly underlie the association with adult traits. As sample sizes are still increasing, it is expected that future analyses will identify additional variants. This, in combination with the development of innovative statistical methods, will provide detailed insight on the mechanisms underlying the transition from childhood to adult disorders. Both consortia welcome new collaborations. Policies and contact details are available from the corresponding authors of this manuscript and/or the consortium websites.
KW  - Genetics
KW  - Consortium
KW  - Childhood traits and disorders
KW  - Longitudinal
Y1  - 2019
U6  - https://doi.org/10.1007/s10654-019-00502-9
SN  - 0393-2990
SN  - 1573-7284
VL  - 34
IS  - 3
SP  - 279
EP  - 300
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - JOUR
A1  - Chipman, Ariel D.
A1  - Ferrier, David E. K.
A1  - Brena, Carlo
A1  - Qu, Jiaxin
A1  - Hughes, Daniel S. T.
A1  - Schroeder, Reinhard
A1  - Torres-Oliva, Montserrat
A1  - Znassi, Nadia
A1  - Jiang, Huaiyang
A1  - Almeida, Francisca C.
A1  - Alonso, Claudio R.
A1  - Apostolou, Zivkos
A1  - Aqrawi, Peshtewani
A1  - Arthur, Wallace
A1  - Barna, Jennifer C. J.
A1  - Blankenburg, Kerstin P.
A1  - Brites, Daniela
A1  - Capella-Gutierrez, Salvador
A1  - Coyle, Marcus
A1  - Dearden, Peter K.
A1  - Du Pasquier, Louis
A1  - Duncan, Elizabeth J.
A1  - Ebert, Dieter
A1  - Eibner, Cornelius
A1  - Erikson, Galina
A1  - Evans, Peter D.
A1  - Extavour, Cassandra G.
A1  - Francisco, Liezl
A1  - Gabaldon, Toni
A1  - Gillis, William J.
A1  - Goodwin-Horn, Elizabeth A.
A1  - Green, Jack E.
A1  - Griffiths-Jones, Sam
A1  - Grimmelikhuijzen, Cornelis J. P.
A1  - Gubbala, Sai
A1  - Guigo, Roderic
A1  - Han, Yi
A1  - Hauser, Frank
A1  - Havlak, Paul
A1  - Hayden, Luke
A1  - Helbing, Sophie
A1  - Holder, Michael
A1  - Hui, Jerome H. L.
A1  - Hunn, Julia P.
A1  - Hunnekuhl, Vera S.
A1  - Jackson, LaRonda
A1  - Javaid, Mehwish
A1  - Jhangiani, Shalini N.
A1  - Jiggins, Francis M.
A1  - Jones, Tamsin E.
A1  - Kaiser, Tobias S.
A1  - Kalra, Divya
A1  - Kenny, Nathan J.
A1  - Korchina, Viktoriya
A1  - Kovar, Christie L.
A1  - Kraus, F. Bernhard
A1  - Lapraz, Francois
A1  - Lee, Sandra L.
A1  - Lv, Jie
A1  - Mandapat, Christigale
A1  - Manning, Gerard
A1  - Mariotti, Marco
A1  - Mata, Robert
A1  - Mathew, Tittu
A1  - Neumann, Tobias
A1  - Newsham, Irene
A1  - Ngo, Dinh N.
A1  - Ninova, Maria
A1  - Okwuonu, Geoffrey
A1  - Ongeri, Fiona
A1  - Palmer, William J.
A1  - Patil, Shobha
A1  - Patraquim, Pedro
A1  - Pham, Christopher
A1  - Pu, Ling-Ling
A1  - Putman, Nicholas H.
A1  - Rabouille, Catherine
A1  - Ramos, Olivia Mendivil
A1  - Rhodes, Adelaide C.
A1  - Robertson, Helen E.
A1  - Robertson, Hugh M.
A1  - Ronshaugen, Matthew
A1  - Rozas, Julio
A1  - Saada, Nehad
A1  - Sanchez-Gracia, Alejandro
A1  - Scherer, Steven E.
A1  - Schurko, Andrew M.
A1  - Siggens, Kenneth W.
A1  - Simmons, DeNard
A1  - Stief, Anna
A1  - Stolle, Eckart
A1  - Telford, Maximilian J.
A1  - Tessmar-Raible, Kristin
A1  - Thornton, Rebecca
A1  - van der Zee, Maurijn
A1  - von Haeseler, Arndt
A1  - Williams, James M.
A1  - Willis, Judith H.
A1  - Wu, Yuanqing
A1  - Zou, Xiaoyan
A1  - Lawson, Daniel
A1  - Muzny, Donna M.
A1  - Worley, Kim C.
A1  - Gibbs, Richard A.
A1  - Akam, Michael
A1  - Richards, Stephen
T1  - The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima
JF  - PLoS biology
N2  - Myriapods (e. g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific life history.
Y1  - 2014
U6  - https://doi.org/10.1371/journal.pbio.1002005
SN  - 1545-7885
VL  - 12
IS  - 11
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - JOUR
A1  - Acciari, V. A.
A1  - Aliu, E.
A1  - Araya, M.
A1  - Arlen, T.
A1  - Aune, T.
A1  - Beilicke, M.
A1  - Benbow, W.
A1  - Bradbury, S. M.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Byrum, K.
A1  - Cannon, A.
A1  - Cesarini, A.
A1  - Ciupik, L.
A1  - Collins-Hughes, E.
A1  - Cui, W.
A1  - Dickherber, R.
A1  - Duke, C.
A1  - Falcone, A.
A1  - Finley, J. P.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Galante, N.
A1  - Gall, D.
A1  - Godambe, S.
A1  - Griffin, S.
A1  - Guenette, R.
A1  - Gyuk, G.
A1  - Hanna, D.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Hui, C. M.
A1  - Humensky, T. B.
A1  - Imran, A.
A1  - Kaaret, P.
A1  - Kertzman, M.
A1  - Krawczynski, H.
A1  - Krennrich, F.
A1  - Madhavan, A. S.
A1  - Maier, G.
A1  - Majumdar, P.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Pandel, D.
A1  - Park, N.
A1  - Perkins, J. S.
A1  - Pohl, Martin
A1  - Prokoph, H.
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reyes, L. C.
A1  - Reynolds, P. T.
A1  - Roache, E.
A1  - Rose, H. J.
A1  - Saxon, D. B.
A1  - Sembroski, G. H.
A1  - Sentuerk, G. D.
A1  - Smith, A. W.
A1  - Tesic, G.
A1  - Theiling, M.
A1  - Thibadeau, S.
A1  - Varlotta, A.
A1  - Vincent, S.
A1  - Vivier, M.
A1  - Wakely, S. P.
A1  - Ward, J. E.
A1  - Weekes, T. C.
A1  - Weinstein, A.
A1  - Weisgarber, T.
A1  - Weng, S.
A1  - Williams, D. A.
A1  - Wood, M.
A1  - Zitzer, B.
T1  - Gamma-ray observations of the Be/Pulsar binary 1A 0535+262 during a Giant X-Ray outburst
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - Giant X-ray outbursts, with luminosities of about 10(37) erg s(-1), are observed roughly every five years from the nearby Be/pulsar binary 1A 0535+262. In this article, we present observations of the source with VERITAS at very high energies (VHEs; E > 100 GeV) triggered by the X-ray outburst in 2009 December. The observations started shortly after the onset of the outburst and provided comprehensive coverage of the episode, as well as the 111 day binary orbit. No VHE emission is evident at any time. We also examined data from the contemporaneous observations of 1A 0535+262 with the Fermi/Large Area Telescope at high-energy photons (E > 0.1 GeV) and failed to detect the source at GeV energies. The X-ray continua measured with the Swift/X-Ray Telescope and the RXTE/PCA can be well described by the combination of blackbody and Comptonized emission from thermal electrons. Therefore, the gamma-ray and X-ray observations suggest the absence of a significant population of non-thermal particles in the system. This distinguishes 1A 0535+262 from those Be X-ray binaries (such as PSR B1259-63 and LS I +61 degrees 303) that have been detected at GeV-TeV energies. We discuss the implications of the results on theoretical models.
KW  - acceleration of particles
KW  - binaries: general
KW  - gamma rays: general
KW  - stars: individual (1A 0535+262)
Y1  - 2011
U6  - https://doi.org/10.1088/0004-637X/733/2/96
SN  - 0004-637X
VL  - 733
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Archer, A.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brill, A.
A1  - Brose, Robert
A1  - Buckley, J. H.
A1  - Christiansen, Jessie L.
A1  - Chromey, A. J.
A1  - Daniel, M. K.
A1  - Falcone, A.
A1  - Feng, Qi
A1  - Finley, John P.
A1  - Fortson, L.
A1  - Furniss, Amy
A1  - Gillanders, Gerard H.
A1  - Gueta, O.
A1  - Hanna, David
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, Caitlin A.
A1  - Kaaret, Philip
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, David
A1  - Krause, Maria
A1  - Krennrich, F.
A1  - Lang, M. J.
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, N.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, Gregory T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, Marcos
A1  - Scott, S. S.
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Williamson, T. J.
A1  - Zitzer, B.
A1  - Kaur, A.
T1  - VERITAS Observations of the BL Lac Object TXS 0506+056
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters
N2  - On 2017 September 22, the IceCube Neutrino Observatory reported the detection of the high-energy neutrino event IC 170922A, of potential astrophysical origin. It was soon determined that the neutrino direction was consistent with the location of the gamma-ray blazar TXS 0506+056. (3FGL J0509.4+ 0541), which was in an elevated gamma-ray emission state as measured by the Fermi satellite. Very Energetic Radiation Imaging Telescope Array System (VERITAS) observations of the neutrino/blazar region started on 2017 September 23 in response to the neutrino alert and continued through 2018 February 6. While no significant very-high-energy (VHE; E > 100 GeV) emission was observed from the blazar by VERITAS in the two-week period immediately following the IceCube alert, TXS 0506+ 056 was detected by VERITAS with a significance of 5.8 standard deviations (sigma) in the full 35 hr data set. The average photon flux of the source during this period was (8.9 +/- 1.6). x. 10(-12) cm(-2) s(-1), or 1.6% of the Crab Nebula flux, above an energy threshold of 110 GeV, with a soft spectral index of 4.8. +/-. 1.3.
KW  - astroparticle physics
KW  - BL Lacertae objects: individual (TXS 0506+056, VER J0509+057)
KW  - gamma rays: galaxies
KW  - quasars: general
KW  - neutrinos
Y1  - 2018
U6  - https://doi.org/10.3847/2041-8213/aad053
SN  - 2041-8205
SN  - 2041-8213
VL  - 861
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Archer, A.
A1  - Aune, Taylor
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Bugaev, V.
A1  - Cui, Wei
A1  - Daniel, M. K.
A1  - Falcone, A.
A1  - Feng, Qi
A1  - Finley, John P.
A1  - Fleischhack, H.
A1  - Flinders, A.
A1  - Fortson, L.
A1  - Furniss, Amy
A1  - Gotthelf, Eric V.
A1  - Grube, J.
A1  - Hanna, David
A1  - Hervet, O.
A1  - Holder, J.
A1  - Huang, K.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Huetten, M.
A1  - Johnson, Caitlin A.
A1  - Kaaret, Philip
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, David
A1  - Krause, Maria
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, Gernot
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Ong, R. A.
A1  - Otte, Adam Nepomuk
A1  - Pandel, Dirk
A1  - Park, Nahee
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Popkow, Alexis
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, Gregory T.
A1  - Roache, E.
A1  - Rousselle, J.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Tyler, J.
A1  - Vassiliev, V. V.
A1  - Wakely, S. P.
A1  - Ward, J. E.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, David A.
A1  - Zitzer, B.
T1  - A Very High Energy gamma-Ray Survey toward the Cygnus Region of the Galaxy
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - We present results from deep observations toward the Cygnus region using 300 hr of very high energy (VHE)gamma-ray data taken with the VERITAS Cerenkov telescope array and over 7 yr of high-energy.-ray data taken with the Fermi satellite at an energy above 1 GeV. As the brightest region of diffuse gamma-ray emission in the northern sky, the Cygnus region provides a promising area to probe the origins of cosmic rays. We report the identification of a potential Fermi-LAT counterpart to VER J2031+415 (TeV J2032+4130) and resolve the extended VHE source VER J2019+368 into two source candidates (VER J2018+367* and VER J2020+368*) and characterize their energy spectra. The Fermi-LAT morphology of 3FGL J2021.0+4031e (the Gamma Cygni supernova remnant) was examined, and a region of enhanced emission coincident with VER J2019+407 was identified and jointly fit with the VERITAS data. By modeling 3FGL J2015.6+3709 as two sources, one located at the location of the pulsar wind nebula CTB 87 and one at the quasar QSO J2015+371, a continuous spectrum from 1 GeV to 10 TeV was extracted for VER J2016+371 (CTB 87). An additional 71 locations coincident with Fermi-LAT sources and other potential objects of interest were tested for VHE gamma-ray emission, with no emission detected and upper limits on the differential flux placed at an average of 2.3% of the Crab Nebula flux. We interpret these observations in a multiwavelength context and present the most detailed gamma-ray view of the region to date.
KW  - acceleration of particles
KW  - cosmic rays
KW  - gamma rays: general
KW  - ISM: supernova remnants
Y1  - 2018
U6  - https://doi.org/10.3847/1538-4357/aac4a2
SN  - 0004-637X
SN  - 1538-4357
VL  - 861
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Archambault, S.
A1  - Archer, A.
A1  - Benbow, W.
A1  - Bird, R.
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Cerruti, M.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Falcone, A.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fleischhack, H.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Gillanders, G. H.
A1  - Griffin, S.
A1  - Grube, J.
A1  - Huetten, M.
A1  - Hanna, D.
A1  - Hervet, O.
A1  - Holder, J.
A1  - Humensky, T. B.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Krennrich, F.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Maier, G.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nieto, D.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, N.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Popkow, A.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, K.
A1  - Staszak, D.
A1  - Telezhinsky, Igor O.
A1  - Tyler, J.
A1  - Vassiliev, V. V.
A1  - Wakely, S. P.
A1  - Weiner, O. M.
A1  - Weinstein, A.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Zitzer, B.
T1  - Discovery of Very-high-energy Emission from RGB J2243+203 and Derivation of Its Redshift Upper Limit
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Supplement series
N2  - Very-high-energy (VHE; > 100 GeV) gamma-ray emission from the blazar RGB J2243+203 was discovered with the VERITAS Cherenkov telescope array, during the period between 2014 December 21 and 24. The VERITAS energy spectrum from this source can be fitted by a power law with a photon index of 4.6 +/- 0.5, and a flux normalization at 0.15 TeV of (6.3 +/- 1.1) x 10(-10) cm(-2) s(-1) TeV-1. The integrated Fermi-LAT flux from 1 to 100 GeV during the VERITAS detection is (4.1 +/- 0.8) x 10(-8) cm(-2) s(-1), which is an order of magnitude larger than the four-year-averaged flux in the same energy range reported in the 3FGL catalog, (4.0 +/- 0.1 x 10(-9) cm(-2) s(-1)). The detection with VERITAS triggered observations in the X-ray band with the Swift-XRT. However, due to scheduling constraints Swift-XRT observations were performed 67 hr after the VERITAS detection, rather than simultaneously with the VERITAS observations. The observed X-ray energy spectrum between 2 and 10 keV can be fitted with a power law with a spectral index of 2.7 +/- 0.2, and the integrated photon flux in the same energy band is (3.6 +/- 0.6) x 10(-13) cm(-2) s(-1). EBL-model-dependent upper limits of the blazar redshift have been derived. Depending on the EBL model used, the upper limit varies in the range from z < 0.9 to z < 1.1.
KW  - galaxies: individual (RGB J2243+203)
Y1  - 2017
U6  - https://doi.org/10.3847/1538-4365/aa8d76
SN  - 0067-0049
SN  - 1538-4365
VL  - 233
SP  - 1188
EP  - 1204
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Archambault, S.
A1  - Archer, A.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Bourbeau, E.
A1  - Buchovecky, M.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Cerruti, M.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Dwarkadas, Vikram V.
A1  - Errando, M.
A1  - Falcone, A.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fleischhack, H.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Griffin, S.
A1  - Huetten, M.
A1  - Hanna, D.
A1  - Holder, J.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Maier, G.
A1  - McArthur, S.
A1  - McCann, A.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nieto, D.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, Nahee
A1  - Pohl, Martin
A1  - Popkow, A.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, K.
A1  - Slane, P.
A1  - Staszak, D.
A1  - Telezhinsky, Igor O.
A1  - Trepanier, S.
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weinstein, A.
A1  - Weisgarber, T.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Zitzer, B.
T1  - Gamma-ray Observations of Tycho's Supernova Remnant with VERITAS and Fermi
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
KW  - material
KW  - data behind figure
Y1  - 2017
U6  - https://doi.org/10.3847/1538-4357/836/1/23
SN  - 0004-637X
SN  - 1538-4357
VL  - 836
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Archer, A.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brill, A.
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Calderon-Madera, D.
A1  - Christiansen, J. L.
A1  - Cui, W.
A1  - Daniel, M. K.
A1  - Falcone, A.
A1  - Feng, Q.
A1  - Fernandez-Alonso, M.
A1  - Finley, J. P.
A1  - Fortson, Lucy
A1  - Furniss, Amy
A1  - Gent, A.
A1  - Giuri, C.
A1  - Gueta, O.
A1  - Hanna, David
A1  - Hassan, T.
A1  - Hervet, Oliver
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, Caitlin A.
A1  - Kaaret, P.
A1  - Kertzman, M.
A1  - Kieda, David
A1  - Krause, Maria
A1  - Krennrich, F.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Maier, Gernot
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Nievas-Rosillo, M.
A1  - Ong, R. A.
A1  - Pfrang, Konstantin Johannes
A1  - Pohl, Martin
A1  - Prado, R. R.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Ribeiro, D.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rovero, A. C.
A1  - Sadeh, Iftach
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Sushch, Iurii
A1  - Svraka, T.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, Patrick
A1  - Wilhelm, Alina
A1  - Williams, David Arnold
A1  - Williamson, T. J.
A1  - Zitzer, B.
T1  - Measurement of the Extragalactic Background Light Spectral Energy Distribution with VERITAS
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - The extragalactic background light (EBL), a diffuse photon field in the optical and infrared range, is a record of radiative processes over the universe?s history. Spectral measurements of blazars at very high energies (>100 GeV) enable the reconstruction of the spectral energy distribution (SED) of the EBL, as the blazar spectra are modified by redshift- and energy-dependent interactions of the gamma-ray photons with the EBL. The spectra of 14 VERITAS-detected blazars are included in a new measurement of the EBL SED that is independent of EBL SED models. The resulting SED covers an EBL wavelength range of 0.56?56 ?m, and is in good agreement with lower limits obtained by assuming that the EBL is entirely due to radiation from cataloged galaxies.
KW  - Extragalactic astronomy
KW  - Active galactic nuclei
KW  - Diffuse radiation
KW  - Cosmology
Y1  - 2019
U6  - https://doi.org/10.3847/1538-4357/ab4817
SN  - 0004-637X
SN  - 1538-4357
VL  - 885
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Archer, A.
A1  - Benbow, W.
A1  - Bird, R.
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Daniel, M. K.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Gillanders, G.
A1  - Huetten, M.
A1  - Hanna, D.
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Krennrich, F.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, G.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Petrashyk, A.
A1  - Pohl, M.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Staszak, D.
A1  - Sushch, I.
A1  - Wakely, S. P.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Williamson, T. J.
A1  - Zitzer, B.
T1  - Measurement of cosmic-ray electrons at TeV energies by VERITAS
JF  - Physical review : D, Particles, fields, gravitation, and cosmology
N2  - Cosmic-ray electrons and positrons (CREs) at GeV-TeV energies are a unique probe of our local Galactic neighborhood. CREs lose energy rapidly via synchrotron radiation and inverse-Compton scattering processes while propagating within the Galaxy, and these losses limit their propagation distance. For electrons with TeV energies, the limit is on the order of a kiloparsec. Within that distance, there are only a few known astrophysical objects capable of accelerating electrons to such high energies. It is also possible that the CREs are the products of the annihilation or decay of heavy dark matter (DM) particles. VERITAS, an array of imaging air Cherenkov telescopes in southern Arizona, is primarily utilized for gamma-ray astronomy but also simultaneously collects CREs during all observations. We describe our methods of identifying CREs in VERITAS data and present an energy spectrum, extending from 300 GeV to 5 TeV, obtained from approximately 300 hours of observations. A single power-law fit is ruled out in VERITAS data. We find that the spectrum of CREs is consistent with a broken power law, with a break energy at 710 +/- 40(stat) +/- 140(syst) GeV.
Y1  - 2018
U6  - https://doi.org/10.1103/PhysRevD.98.062004
SN  - 2470-0010
SN  - 2470-0029
VL  - 98
IS  - 6
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Benbow, W.
A1  - Bird, R.
A1  - Brill, A.
A1  - Brose, Robert
A1  - Chromey, A. J.
A1  - Daniel, M. K.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Gillanders, G. H.
A1  - Giuri, C.
A1  - Gueta, O.
A1  - Hanna, D.
A1  - Halpern, J. P.
A1  - Hassan, Tarek
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Joyce, Amy M.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, Gernot
A1  - Matthews, N.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nieto, D.
A1  - Nievas-Rosillos, M.
A1  - Ong, R. A.
A1  - Park, N.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Pueschel, Elisa
A1  - Quinn, John
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, Iftach
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, K.
A1  - Sushch, Iurii
A1  - Wakely, S. P.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, David A.
A1  - Williamson, T. J.
T1  - Direct measurement of stellar angular diameters by the VERITAS Cherenkov telescopes
JF  - Nature astronomy
N2  - The angular size of a star is a critical factor in determining its basic properties1. Direct measurement of stellar angular diameters is difficult: at interstellar distances stars are generally too small to resolve by any individual imaging telescope. This fundamental limitation can be overcome by studying the diffraction pattern in the shadow cast when an asteroid occults a star2, but only when the photometric uncertainty is smaller than the noise added by atmospheric scintillation3. Atmospheric Cherenkov telescopes used for particle astrophysics observations have not generally been exploited for optical astronomy due to the modest optical quality of the mirror surface. However, their large mirror area makes them well suited for such high-time-resolution precision photometry measurements4. Here we report two occultations of stars observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS)5 Cherenkov telescopes with millisecond sampling, from which we are able to provide a direct measurement of the occulted stars’ angular diameter at the ≤0.1 mas scale. This is a resolution never achieved before with optical measurements and represents an order of magnitude improvement over the equivalent lunar occultation method6. We compare the resulting stellar radius with empirically derived estimates from temperature and brightness measurements, confirming the latter can be biased for stars with ambiguous stellar classifications.
Y1  - 2019
U6  - https://doi.org/10.1038/s41550-019-0741-z
SN  - 2397-3366
VL  - 3
IS  - 6
SP  - 511
EP  - 516
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Archambault, S.
A1  - Archer, A.
A1  - Benbow, W.
A1  - Buchovecky, M.
A1  - Bugaev, V.
A1  - Cerruti, M.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Falcone, A.
A1  - Alonso, M. Fernandez
A1  - Finley, J. P.
A1  - Fleischhack, H.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Griffin, S.
A1  - Hutten, M.
A1  - Hervet, O.
A1  - Holder, J.
A1  - Humensky, T. B.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Krennrich, F.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, G.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Nieto, D.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Pohl, M.
A1  - Popkow, A.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rovero, A. C.
A1  - Sadeh, I.
A1  - Shahinyan, K.
A1  - Staszak, D.
A1  - Telezhinsky, Igor O.
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weinstein, A.
A1  - Weisgarber, T.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Zitzer, B.
T1  - Search for Magnetically Broadened Cascade Emission from Blazars with VERITAS
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - We present a search for magnetically broadened gamma-ray emission around active galactic nuclei (AGNs), using VERITAS observations of seven hard-spectrum blazars. A cascade process occurs when multi-TeV gamma-rays from an AGN interact with extragalactic background light (EBL) photons to produce electron-positron pairs, which then interact with cosmic microwave background photons via inverse-Compton scattering to produce gamma-rays. Due to the deflection of the electron- positron pairs, a non-zero intergalactic magnetic field (IGMF) would potentially produce detectable effects on the angular distribution of the cascade emission. In particular, an angular broadening compared to the unscattered emission could occur. Through non-detection of angularly broadened emission from 1ES 1218 vertical bar 304, the source with the largest predicted cascade fraction, we exclude a range of IGMF strengths around 10(-14) G at the 95% confidence level. The extent of the exclusion range varies with the assumptions made about the intrinsic spectrum of 1ES. 1218+304 and the EBL model used in the simulation of the cascade process. All of the sources are used to set limits on the flux due to extended emission.
KW  - BL Lacertae objects: general
KW  - galaxies: active
KW  - gamma rays: galaxies
KW  - magnetic fields
Y1  - 2017
U6  - https://doi.org/10.3847/1538-4357/835/2/288
SN  - 0004-637X
SN  - 1538-4357
VL  - 835
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brantseg, T.
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Buckley, J. H.
A1  - Bugaev, V.
A1  - Connolly, M. P.
A1  - Cui, Wei
A1  - Daniel, M. K.
A1  - Falcone, A.
A1  - Feng, Qi
A1  - Finley, John P.
A1  - Fortson, L.
A1  - Furniss, Amy
A1  - Gillanders, Gerard H.
A1  - Gunawardhana, Isuru
A1  - Huetten, M.
A1  - Hanna, David
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, Caitlin A.
A1  - Kaaret, Philip
A1  - Kar, P.
A1  - Kertzman, M.
A1  - Krennrich, F.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Ong, R. A.
A1  - Otte, Adam Nepomuk
A1  - Park, N.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, Gregory T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Wakely, S. P.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Williams, D. A.
A1  - Zitzer, B.
A1  - Jorstad, Svetlana G.
A1  - Marscher, Alan P.
A1  - Lister, Matthew L.
A1  - Kovalev, Yuri Y.
A1  - Pushkarev, A. B.
A1  - Savolainen, Tuomas
A1  - Agudo, I.
A1  - Molina, S. N.
A1  - Gomez, J. L.
A1  - Larionov, Valeri M.
A1  - Borman, G. A.
A1  - Mokrushina, A. A.
A1  - Tornikoski, Merja
A1  - Lahteenmaki, A.
A1  - Chamani, W.
A1  - Enestam, S.
A1  - Kiehlmann, S.
A1  - Hovatta, Talvikki
A1  - Smith, P. S.
A1  - Pontrelli, P.
T1  - Multiwavelength Observations of the Blazar BL Lacertae
BT  - a new Fast TeV Gamma-Ray Flare
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - Combined with measurements made by very-long-baseline interferometry, the observations of fast TeV gamma-ray flares probe the structure and emission mechanism of blazar jets. However, only a handful of such flares have been detected to date, and only within the last few years have these flares been observed from lower-frequency-peaked BL. Lac objects and flat-spectrum radio quasars. We report on a fast TeV gamma-ray flare from the blazar BL. Lacertae observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). with a rise time of similar to 2.3 hr and a decay time of similar to 36 min. The peak flux above 200 GeV is (4.2 +/- 0.6) x 10(-6) photon m(-2) s(-1) measured with a 4-minute-binned light curve, corresponding to similar to 180% of the flux that is observed from the Crab Nebula above the same energy threshold. Variability contemporaneous with the TeV gamma-ray flare was observed in GeV gamma-ray, X-ray, and optical flux, as well as in optical and radio polarization. Additionally, a possible moving emission feature with superluminal apparent velocity was identified in Very Long Baseline Array observations at 43 GHz, potentially passing the radio core of the jet around the time of the gamma-ray flare. We discuss the constraints on the size, Lorentz factor, and location of the emitting region of the flare, and the interpretations with several theoretical models that invoke relativistic plasma passing stationary shocks.
KW  - BL Lacertae objects: individual (BL Lacertae = VER J2202+422)
KW  - galaxies: active
Y1  - 2018
U6  - https://doi.org/10.3847/1538-4357/aab35c
SN  - 0004-637X
SN  - 1538-4357
VL  - 856
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Archambault, S.
A1  - Archer, A.
A1  - Benbow, W.
A1  - Bird, Ralph
A1  - Bourbeau, E.
A1  - Bouvier, A.
A1  - Buchovecky, M.
A1  - Bugaev, V.
A1  - Cardenzana, J. V.
A1  - Cerruti, M.
A1  - Ciupik, L.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Daniel, M. K.
A1  - Errando, M.
A1  - Falcone, A.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fleischhack, H.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Gillanders, G. H.
A1  - Griffin, S.
A1  - Hanna, D.
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Hutten, M.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kar, P.
A1  - Kertzman, M.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, G.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nieto, D.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, N.
A1  - Pohl, Martin
A1  - Popkow, A.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Sembroski, G. H.
A1  - Shahinyan, K.
A1  - Staszak, D.
A1  - Telezhinsky, Igor O.
A1  - Trepanier, S.
A1  - Wakely, S. P.
A1  - Weinstein, A.
A1  - Wilcox, P.
A1  - Williams, D. A.
A1  - Zitzer, B.
T1  - Gamma-ray observations under bright moonlight with VERITAS
JF  - Astroparticle physics
N2  - Imaging atmospheric Cherenkov telescopes (IACTs) are equipped with sensitive photomultiplier tube (PMT) cameras. Exposure to high levels of background illumination degrades the efficiency of and potentially destroys these photo-detectors over time, so IACTs cannot be operated in the same configuration in the presence of bright moonlight as under dark skies. Since September 2012, observations have been carried out with the VERITAS IACTs under bright moonlight (defined as about three times the night-sky-background (NSB) of a dark extragalactic field, typically occurring when Moon illumination > 35%) in two observing modes, firstly by reducing the voltage applied to the PMTs and, secondly, with the addition of ultra-violet (UV) bandpass filters to the cameras. This has allowed observations at up to about 30 times previous NSB levels (around 80% Moon illumination), resulting in 30% more observing time between the two modes over the course of a year. These additional observations have already allowed for the detection of a flare from the 1ES 1727 + 502 and for an observing program targeting a measurement of the cosmic-ray positron fraction. We provide details of these new observing modes and their performance relative to the standard VERITAS observations. (C) 2017 Elsevier B.V. All rights reserved.
KW  - Instrumentation
KW  - Moonlight
KW  - Observing methods
KW  - VERITAS
KW  - IACT
Y1  - 2017
U6  - https://doi.org/10.1016/j.astropartphys.2017.03.001
SN  - 0927-6505
SN  - 1873-2852
VL  - 91
SP  - 34
EP  - 43
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Archer, A.
A1  - Benbow, W.
A1  - Bird, R.
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Bugaev, V.
A1  - Connolly, M. P.
A1  - Cui, W.
A1  - Daniel, M. K.
A1  - Falcone, A.
A1  - Feng, Q.
A1  - Finley, J. P.
A1  - Fleischhack, H.
A1  - Fortson, L.
A1  - Furniss, A.
A1  - Hanna, D.
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Hutten, M.
A1  - Johnson, C. A.
A1  - Kaaret, P.
A1  - Kelley-Hoskins, N.
A1  - Kieda, D.
A1  - Krause, M.
A1  - Krennrich, F.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Maier, G.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, R.
A1  - Nieto, D.
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, N.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Popkow, A.
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, G. T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weiner, O. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, D. A.
A1  - Wissel, S. A.
A1  - Zitzer, B.
T1  - Measurement of the iron spectrum in cosmic rays by VERITAS
JF  - Physical review : D, Particles, fields, gravitation, and cosmology
N2  - We present a new measurement of the energy spectrum of iron nuclei in cosmic rays from 20 TeV to 500 TeV; The measurement makes use of a template-based analysis method, which, for the first time, is applied to the energy reconstruction of iron-induced air showers recorded by the VERITAS array of imaging atmospheric Cherenkov telescopes. The event selection makes use of the direct Cherenkov light which is emitted by charged particles before the first interaction, as well as other parameters related to the shape of the recorded air shower images. The measured spectrum is well described by a power law dF/dE = f(0) center dot (E/E-0)(-gamma) over the full energy range, with gamma = 2.82 +/- 0.30(stat)(-0.27)(+0.24)(syst) and f(0) = (4.82 +/- 0.98(stat)(-2.70)(+2.12)(syst)) x 10(-7) m(-2) s(-1) TeV-1 sr(-1) at E-0 = 50 TeV, with no indication of a cutoff or spectral break. The measured differential flux is compatible with previous results, with improved statistical uncertainty at the highest energies.
Y1  - 2018
U6  - https://doi.org/10.1103/PhysRevD.98.022009
SN  - 2470-0010
SN  - 2470-0029
VL  - 98
IS  - 2
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Archer, A.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Bugaev, V
A1  - Cui, Wei
A1  - Danie, M. K.
A1  - Falcone, A.
A1  - Feng, Qi
A1  - Finley, John P.
A1  - Flinders, A.
A1  - Fortson, L.
A1  - Furniss, Amy
A1  - Gillanders, Gerard H.
A1  - Huttens, M.
A1  - Hanna, David
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, Caitlin A.
A1  - Kaaret, Philip
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kieda, David
A1  - Krause, Maria
A1  - Krennrich, F.
A1  - Kumar, S.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Nieto, Daniel
A1  - Ong, R. A.
A1  - Otte, A. N.
A1  - Park, Nahee
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Popkow, Alexis
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynold, P. T.
A1  - Richards, Gregory T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weiner, O. M.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, David A.
A1  - Brisken, W. F.
A1  - Pontrelli, P.
T1  - HESS J1943+213
BT  - An extreme blazar shining through the galactic plane
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - HESS J1943+213 is a very high energy (VHE; > 100 GeV) gamma-ray source in the direction of the Galactic plane. Studies exploring the classification of the source are converging toward its identification as an extreme synchrotron BL Lac object. Here we present 38 hr of VERITAS observations of HESS J1943+213 taken over 2 yr. The source is detected with a significance of similar to 20 standard deviations, showing a remarkably stable flux and spectrum in VHE gamma-rays. Multifrequency Very Long Baseline Array (VLBA) observations of the source confirm the extended, jet-like structure previously found in the 1.6 GHz band with the European VLBI Network and detect this component in the 4.6 and 7.3 GHz bands. The radio spectral indices of the core and the jet and the level of polarization derived from the VLBA observations are in a range typical for blazars. Data from VERITAS, Fermi-LAT, Swift-XRT, the FLWO 48 ' telescope, and archival infrared and hard X-ray observations are used to construct and model the spectral energy distribution (SED) of the source with a synchrotron self-Compton model. The well-measured gamma-ray peak of the SED with VERITAS and Fermi-LAT provides constraining upper limits on the source redshift. Possible contribution of secondary gamma-rays from ultra-high-energy cosmic-ray-initiated electromagnetic cascades to the gamma-ray emission is explored, finding that only a segment of the VHE spectrum can be accommodated with this process. A variability search is performed across X-ray and gamma-ray bands. No statistically significant flux or spectral variability is detected.
KW  - astroparticle physics
KW  - BL Lacertae objects: individual (HESS J1943+213, VER J1943+213)
KW  - galaxies: active
KW  - galaxies: jets
KW  - galaxies: nuclei
KW  - gamma rays: galaxies
Y1  - 2018
U6  - https://doi.org/10.3847/1538-4357/aacbd0
SN  - 0004-637X
SN  - 1538-4357
VL  - 862
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Abeysekara, A. U.
A1  - Archer, A.
A1  - Benbow, Wystan
A1  - Bird, Ralph
A1  - Brose, Robert
A1  - Buchovecky, M.
A1  - Bugaev, V.
A1  - Connolly, M. P.
A1  - Cui, Wei
A1  - Errando, Manel
A1  - Falcone, A.
A1  - Feng, Qi
A1  - Finley, John P.
A1  - Flinders, A.
A1  - Fortson, L.
A1  - Furniss, Amy
A1  - Gillanders, Gerard H.
A1  - Huetten, M.
A1  - Hanna, David
A1  - Hervet, O.
A1  - Holder, J.
A1  - Hughes, G.
A1  - Humensky, T. B.
A1  - Johnson, Caitlin A.
A1  - Kaaret, Philip
A1  - Kar, P.
A1  - Kelley-Hoskins, N.
A1  - Kertzman, M.
A1  - Kieda, David
A1  - Krause, Maria
A1  - Krennrich, F.
A1  - Lang, M. J.
A1  - Lin, T. T. Y.
A1  - Maier, Gernot
A1  - McArthur, S.
A1  - Moriarty, P.
A1  - Mukherjee, Reshmi
A1  - Ong, R. A.
A1  - Park, N.
A1  - Perkins, Jeremy S.
A1  - Petrashyk, A.
A1  - Pohl, Martin
A1  - Popkow, Alexis
A1  - Pueschel, Elisa
A1  - Quinn, J.
A1  - Ragan, K.
A1  - Reynolds, P. T.
A1  - Richards, Gregory T.
A1  - Roache, E.
A1  - Rulten, C.
A1  - Sadeh, I.
A1  - Santander, M.
A1  - Sembroski, G. H.
A1  - Shahinyan, Karlen
A1  - Tyler, J.
A1  - Wakely, S. P.
A1  - Weiner, O. M.
A1  - Weinstein, A.
A1  - Wells, R. M.
A1  - Wilcox, P.
A1  - Wilhelm, Alina
A1  - Williams, David A.
A1  - Zitzer, B.
A1  - Vurm, Indrek
A1  - Beloborodov, Andrei
T1  - A Strong Limit on the Very-high-energy Emission from GRB 150323A
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - On 2015 March 23, the Very Energetic Radiation Imaging Telescope Array System (VERITAS) responded to a Swift-Burst Alert Telescope (BAT) detection of a gamma-ray burst, with observations beginning 270 s after the onset of BAT emission, and only 135 s after the main BAT emission peak. No statistically significant signal is detected above 140 GeV. The VERITAS upper limit on the fluence in a 40-minute integration corresponds to about 1% of the prompt fluence. Our limit is particularly significant because the very-high-energy (VHE) observation started only similar to 2 minutes after the prompt emission peaked, and Fermi-Large Area Telescope observations of numerous other bursts have revealed that the high-energy emission is typically delayed relative to the prompt radiation and lasts significantly longer. Also, the proximity of GRB 150323A (z = 0.593) limits the attenuation by the extragalactic background light to similar to 50% at 100-200 GeV. We conclude that GRB 150323A had an intrinsically very weak high-energy afterglow, or that the GeV spectrum had a turnover below similar to 100 GeV. If the GRB exploded into the stellar wind of a massive progenitor, the VHE non-detection constrains the wind density parameter to be A greater than or similar to 3 x 10(11) g . cm(-1), consistent with a standard Wolf-Rayet progenitor. Alternatively, the VHE emission from the blast wave would be weak in a very tenuous medium such as the interstellar medium, which therefore cannot be ruled out as the environment of GRB 150323A.
KW  - gamma rays: general
KW  - gamma-ray burst: general
KW  - gamma-ray burst: individual (GRB 150323A)
Y1  - 2018
U6  - https://doi.org/10.3847/1538-4357/aab371
SN  - 0004-637X
SN  - 1538-4357
VL  - 857
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Read, Betsy A.
A1  - Kegel, Jessica
A1  - Klute, Mary J.
A1  - Kuo, Alan
A1  - Lefebvre, Stephane C.
A1  - Maumus, Florian
A1  - Mayer, Christoph
A1  - Miller, John
A1  - Monier, Adam
A1  - Salamov, Asaf
A1  - Young, Jeremy
A1  - Aguilar, Maria
A1  - Claverie, Jean-Michel
A1  - Frickenhaus, Stephan
A1  - Gonzalez, Karina
A1  - Herman, Emily K.
A1  - Lin, Yao-Cheng
A1  - Napier, Johnathan
A1  - Ogata, Hiroyuki
A1  - Sarno, Analissa F.
A1  - Shmutz, Jeremy
A1  - Schroeder, Declan
A1  - de Vargas, Colomban
A1  - Verret, Frederic
A1  - von Dassow, Peter
A1  - Valentin, Klaus
A1  - Van de Peer, Yves
A1  - Wheeler, Glen
A1  - Dacks, Joel B.
A1  - Delwiche, Charles F.
A1  - Dyhrman, Sonya T.
A1  - Glöckner, Gernot
A1  - John, Uwe
A1  - Richards, Thomas
A1  - Worden, Alexandra Z.
A1  - Zhang, Xiaoyu
A1  - Grigoriev, Igor V.
A1  - Allen, Andrew E.
A1  - Bidle, Kay
A1  - Borodovsky, M.
A1  - Bowler, C.
A1  - Brownlee, Colin
A1  - Cock, J. Mark
A1  - Elias, Marek
A1  - Gladyshev, Vadim N.
A1  - Groth, Marco
A1  - Guda, Chittibabu
A1  - Hadaegh, Ahmad
A1  - Iglesias-Rodriguez, Maria Debora
A1  - Jenkins, J.
A1  - Jones, Bethan M.
A1  - Lawson, Tracy
A1  - Leese, Florian
A1  - Lindquist, Erika
A1  - Lobanov, Alexei
A1  - Lomsadze, Alexandre
A1  - Malik, Shehre-Banoo
A1  - Marsh, Mary E.
A1  - Mackinder, Luke
A1  - Mock, Thomas
A1  - Müller-Röber, Bernd
A1  - Pagarete, Antonio
A1  - Parker, Micaela
A1  - Probert, Ian
A1  - Quesneville, Hadi
A1  - Raines, Christine
A1  - Rensing, Stefan A.
A1  - Riano-Pachon, Diego Mauricio
A1  - Richier, Sophie
A1  - Rokitta, Sebastian
A1  - Shiraiwa, Yoshihiro
A1  - Soanes, Darren M.
A1  - van der Giezen, Mark
A1  - Wahlund, Thomas M.
A1  - Williams, Bryony
A1  - Wilson, Willie
A1  - Wolfe, Gordon
A1  - Wurch, Louie L.
T1  - Pan genome of the phytoplankton Emiliania underpins its global distribution
JF  - Nature : the international weekly journal of science
N2  - Coccolithophores have influenced the global climate for over 200 million years(1). These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems(2). They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering them visible from space(3). Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean(4). Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate that E. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.
Y1  - 2013
U6  - https://doi.org/10.1038/nature12221
SN  - 0028-0836
SN  - 1476-4687
VL  - 499
IS  - 7457
SP  - 209
EP  - 213
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Kubas, Daniel
A1  - Cassan, A.
A1  - Beaulieu, Jean-Philippe
A1  - Coutures, C.
A1  - Dominik, M.
A1  - Albrow, Michael D.
A1  - Brillant, Stephane
A1  - Caldwell, John A. R.
A1  - Dominis, Dijana
A1  - Donatowicz, J.
A1  - Fendt, Christian
A1  - Fouque, P.
A1  - Jorgensen, Uffe Grae
A1  - Greenhill, John
A1  - Hill, K.
A1  - Heinmüller, Janine
A1  - Horne, Keith
A1  - Kane, Stephen R.
A1  - Marquette, Jean-Baptiste
A1  - Martin, Ralph
A1  - Menzies, J. W.
A1  - Pollard, K. R.
A1  - Sahu, K. C.
A1  - Vinter, C.
A1  - Wambsganss, Joachim
A1  - Watson, R.
A1  - Williams, A.
A1  - Thurl, C.
T1  - Full characterization of binary-lens event OGLE-2002-BLG-069 from PLANET observations
N2  - We analyze the photometric data obtained by PLANET and OGLE on the caustic-crossing binary-lens microlensing event OGLE-2002-BLG-069. Thanks to the excellent photometric and spectroscopic coverage of the event, we are able to constrain the lens model up to the known ambiguity between close and wide binary lenses. The detection of annual parallax in combination with measurements of extended-source effects allows us to determine the mass, distance and velocity of the lens components for the competing models. While the model involving a close binary lens leads to a Bulge- Disc lens scenario with a lens mass of M = (0.51 ± 0.15) M-&ODOT; and distance of D-L = (2.9 ± 0.4) kpc, the wide binary lens solution requires a rather implausible binary black-hole lens ( M &GSIM; 126 M-&ODOT;). Furthermore we compare current state-of-the-art numerical and empirical models for the surface brightness profile of the source, a G5III Bulge giant. We find that a linear limb-darkening model for the atmosphere of the source star is consistent with the data whereas a PHOENIX atmosphere model assuming LTE and with no free parameter does not match our observations
Y1  - 2005
SN  - 0004-6361
ER  - 
TY  - JOUR
A1  - Sandee, A. J.
A1  - Williams, Charlotte K.
A1  - Evans, N. R.
A1  - Davies, J. E.
A1  - Boothby, C. E.
A1  - Köhler, Anna
A1  - Friend, Richard H.
A1  - Holmes, Andrew B.
T1  - Solution-processible conjugated electrophosphorescent polymers
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Cassan, A.
A1  - Beaulieu, Jean-Philippe
A1  - Brillant, Stephane
A1  - Coutures, C.
A1  - Dominik, M.
A1  - Donatowicz, J.
A1  - Jorgensen, Uffe Grae
A1  - Kubas, Daniel
A1  - Albrow, Michael D.
A1  - Caldwell, John A. R.
A1  - Fouque, P.
A1  - Greenhill, John
A1  - Hill, K.
A1  - Horne, Keith
A1  - Kane, Stephen R.
A1  - Martin, Ralph
A1  - Menzies, J. W.
A1  - Pollard, K. R.
A1  - Sahu, K. C.
A1  - Vinter, C.
A1  - Wambsganss, Joachim
A1  - Watson, R.
A1  - Williams, A.
A1  - Fendt, Christian
A1  - Hauschildt, P.
A1  - Heinmueller, Janine
A1  - Marquette, Jean-Baptiste
A1  - Thurl, C.
T1  - Probing the atmosphere of the bulge G5III star OGLE-2002-BUL-069 by analysis of microlensed H alpha line
N2  - We discuss high-resolution, time-resolved spectra of the caustic exit of the binary microlensing event OGLE 2002-BLG-069 obtained with UVES on the VLT. The source star is a G5III giant in the Galactic Bulge. During such events, the source star is highly magnified, and a strong differential magnification around the caustic resolves its surface. Using an appropriate model stellar atmosphere generated by the PHOENIX v2.6 code we obtain a model light curve for the caustic exit and compare it with a dense set of photometric observations obtained by the PLANET microlensing follow up network. We further compare predicted variations in the Halpha equivalent width with those measured from our spectra. While the model and observations agree in the gross features, there are discrepancies suggesting shortcomings in the model, particularly for the Halpha line core, where we have detected amplified emission from the stellar chromosphere after the source star's trailing limb exited the caustic. This achievement became possible by the provision of the very efficient OGLE-III Early Warning System, a network of small telescopes capable of nearly-continuous round-the-clock photometric monitoring, on-line data reduction, daily near-real-time modelling in order to predict caustic crossing parameters, and a fast and efficient response of a 8 m class telescope to a "Target-of-Opportunity" observation request
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Jiang, G. F.
A1  - DePoy, D. L.
A1  - Gal-Yam, A.
A1  - Gaudi, B. S.
A1  - Gould, A.
A1  - Han, C.
A1  - Lipkin, Y.
A1  - Maoz, D.
A1  - Ofek, E. O.
A1  - Park, B. G.
A1  - Pogge, R. W.
A1  - Udalski, A.
A1  - Kubiak, Marcin
A1  - Szymanski, M. K.
A1  - Szewczyk, O.
A1  - Zerbrun, K.
A1  - Wyrzykowski, L.
A1  - Soszynski, I.
A1  - Pietrzynski, G.
A1  - Albrow, Michael D.
A1  - Beaulieu, Jean-Philippe
A1  - Caldwell, John A. R.
A1  - Cassan, A.
A1  - Coutures, C.
A1  - Dominik, M.
A1  - Donatowicz, J.
A1  - Fouque, P.
A1  - Greenhill, John
A1  - Hill, K.
A1  - Horne, Keith
A1  - Jorgensen, S. F.
A1  - Jorgensen, Uffe Grae
A1  - Kane, Stephen R.
A1  - Kubas, Daniel
A1  - Martin, Ralph
A1  - Menzies, J. W.
A1  - Pollard, R.
A1  - Sahu, K. C.
A1  - Wambsganss, Joachim
A1  - Watson, R.
A1  - Williams, A.
T1  - OGLE-2003-BLG-238 : Microlensing mass estimate of an isolated star
N2  - Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M (c(2)/4G)(r) over tilde (E)theta(E) and so requires the measurement of both the angular Einstein radius theta(E) and the projected Einstein radius (r) over tilde (E). Simultaneous measurement of these two parameters is extremely rare. Here we analyze OGLE-2003-BLG-238, a spectacularly bright (I-min 10.3), high-magnification (A(max) 170) microlensing event. Pronounced finite-source effects permit a measurement of theta(E) = 650 muas. Although the timescale of the event is only t(E) 38 days, one can still obtain weak constraints on the microlens parallax: 4.4 AU < <(r)over tilde>(E) < 18 AU at the 1 &sigma; level. Together these two parameter measurements yield a range for the lens mass of 0.36 M-&ODOT; < M < 1.48 M-&ODOT;. As was the case for MACHO- LMC-5, the only other single star (apart from the Sun) whose mass has been determined from its gravitational effects, this estimate is rather crude. It does, however, demonstrate the viability of the technique. We also discuss future prospects for single-lens mass measurements
Y1  - 2004
SN  - 0004-637X
ER  - 
TY  - JOUR
A1  - Treat, Claire C.
A1  - Kleinen, Thomas
A1  - Broothaerts, Nils
A1  - Dalton, April S.
A1  - Dommain, Rene
A1  - Douglas, Thomas A.
A1  - Drexler, Judith Z.
A1  - Finkelstein, Sarah A.
A1  - Grosse, Guido
A1  - Hope, Geoffrey
A1  - Hutchings, Jack
A1  - Jones, Miriam C.
A1  - Kuhry, Peter
A1  - Lacourse, Terri
A1  - Lahteenoja, Outi
A1  - Loisel, Julie
A1  - Notebaert, Bastiaan
A1  - Payne, Richard J.
A1  - Peteet, Dorothy M.
A1  - Sannel, A. Britta K.
A1  - Stelling, Jonathan M.
A1  - Strauss, Jens
A1  - Swindles, Graeme T.
A1  - Talbot, Julie
A1  - Tarnocai, Charles
A1  - Verstraeten, Gert
A1  - Williams, Christopher J.
A1  - Xia, Zhengyu
A1  - Yu, Zicheng
A1  - Valiranta, Minna
A1  - Hattestrand, Martina
A1  - Alexanderson, Helena
A1  - Brovkin, Victor
T1  - Widespread global peatland establishment and persistence over the last 130,000 y
JF  - Proceedings of the National Academy of Sciences of the United States of America
N2  - Glacial-interglacial variations in CO2 and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (> 40 degrees N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.
KW  - peatlands
KW  - carbon
KW  - methane
KW  - carbon burial
KW  - Quaternary
Y1  - 2019
U6  - https://doi.org/10.1073/pnas.1813305116
SN  - 0027-8424
VL  - 116
IS  - 11
SP  - 4822
EP  - 4827
PB  - National Acad. of Sciences
CY  - Washington
ER  - 
TY  - JOUR
A1  - Toy, Virginia Gail
A1  - Sutherland, Rupert
A1  - Townend, John
A1  - Allen, Michael J.
A1  - Becroft, Leeza
A1  - Boles, Austin
A1  - Boulton, Carolyn
A1  - Carpenter, Brett
A1  - Cooper, Alan
A1  - Cox, Simon C.
A1  - Daube, Christopher
A1  - Faulkner, D. R.
A1  - Halfpenny, Angela
A1  - Kato, Naoki
A1  - Keys, Stephen
A1  - Kirilova, Martina
A1  - Kometani, Yusuke
A1  - Little, Timothy
A1  - Mariani, Elisabetta
A1  - Melosh, Benjamin
A1  - Menzies, Catriona D.
A1  - Morales, Luiz
A1  - Morgan, Chance
A1  - Mori, Hiroshi
A1  - Niemeijer, Andre
A1  - Norris, Richard
A1  - Prior, David
A1  - Sauer, Katrina
A1  - Schleicher, Anja Maria
A1  - Shigematsu, Norio
A1  - Teagle, Damon A. H.
A1  - Tobin, Harold
A1  - Valdez, Robert
A1  - Williams, Jack
A1  - Yeo, Samantha
A1  - Baratin, Laura-May
A1  - Barth, Nicolas
A1  - Benson, Adrian
A1  - Boese, Carolin
A1  - Célérier, Bernard
A1  - Chamberlain, Calum J.
A1  - Conze, Ronald
A1  - Coussens, Jamie
A1  - Craw, Lisa
A1  - Doan, Mai-Linh
A1  - Eccles, Jennifer
A1  - Grieve, Jason
A1  - Grochowski, Julia
A1  - Gulley, Anton
A1  - Howarth, Jamie
A1  - Jacobs, Katrina
A1  - Janku-Capova, Lucie
A1  - Jeppson, Tamara
A1  - Langridge, Robert
A1  - Mallyon, Deirdre
A1  - Marx, Ray
A1  - Massiot, Cécile
A1  - Mathewson, Loren
A1  - Moore, Josephine
A1  - Nishikawa, Osamu
A1  - Pooley, Brent
A1  - Pyne, Alex
A1  - Savage, Martha K.
A1  - Schmitt, Doug
A1  - Taylor-Offord, Sam
A1  - Upton, Phaedra
A1  - Weaver, Konrad C.
A1  - Wiersberg, Thomas
A1  - Zimmer, Martin
T1  - Bedrock geology of DFDP-2B, central Alpine Fault, New Zealand
JF  - New Zealand journal of geology and geophysics : an international journal of the geoscience of New Zealand, the Pacific Rim, and Antarctica ; NZJG
N2  - During the second phase of the Alpine Fault, Deep Fault Drilling Project (DFDP) in the Whataroa River, South Westland, New Zealand, bedrock was encountered in the DFDP-2B borehole from 238.5–893.2 m Measured Depth (MD). Continuous sampling and meso- to microscale characterisation of whole rock cuttings established that, in sequence, the borehole sampled amphibolite facies, Torlesse Composite Terrane-derived schists, protomylonites and mylonites, terminating 200–400 m above an Alpine Fault Principal Slip Zone (PSZ) with a maximum dip of 62°. The most diagnostic structural features of increasing PSZ proximity were the occurrence of shear bands and reduction in mean quartz grain sizes. A change in composition to greater mica:quartz + feldspar, most markedly below c. 700 m MD, is inferred to result from either heterogeneous sampling or a change in lithology related to alteration. Major oxide variations suggest the fault-proximal Alpine Fault alteration zone, as previously defined in DFDP-1 core, was not sampled.
KW  - Alpine Fault
KW  - New Zealand
KW  - scientific drilling
KW  - mylonite
KW  - cataclasite
Y1  - 2017
U6  - https://doi.org/10.1080/00288306.2017.1375533
SN  - 0028-8306
SN  - 1175-8791
VL  - 60
IS  - 4
SP  - 497
EP  - 518
PB  - Taylor & Francis
CY  - Abingdon
ER  - 
TY  - JOUR
A1  - van Driel-Gesztelyi, L.
A1  - Baker, Daniel N.
A1  - Toeroek, T.
A1  - Pariat, E.
A1  - Green, L. M.
A1  - Williams, D. R.
A1  - Carlyle, J.
A1  - Valori, G.
A1  - Demoulin, Pascal
A1  - Kliem, Bernhard
A1  - Long, D. M.
A1  - Matthews, S. A.
A1  - Malherbe, J. -M.
T1  - Coronal magnetic reconnection driven by CME expansion-the 2011 June 7  event
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - Coronal mass ejections (CMEs) erupt and expand in a magnetically structured solar corona. Various indirect observational pieces of evidence have shown that the magnetic field of CMEs reconnects with surrounding magnetic fields, forming, e.g., dimming regions distant from the CME source regions. Analyzing Solar Dynamics Observatory (SDO) observations of the eruption from AR 11226 on 2011 June 7, we present the first direct evidence of coronal magnetic reconnection between the fields of two adjacent active regions during a CME. The observations are presented jointly with a data-constrained numerical simulation, demonstrating the formation/intensification of current sheets along a hyperbolic flux tube at the interface between the CME and the neighboring AR 11227. Reconnection resulted in the formation of new magnetic connections between the erupting magnetic structure from AR 11226 and the neighboring active region AR 11227 about 200 Mm from the eruption site. The onset of reconnection first becomes apparent in the SDO/AIA images when filament plasma, originally contained within the erupting flux rope, is redirected toward remote areas in AR 11227, tracing the change of large-scale magnetic connectivity. The location of the coronal reconnection region becomes bright and directly observable at SDO/AIA wavelengths, owing to the presence of down-flowing cool, dense (1010 cm(-3)) filament plasma in its vicinity. The high-density plasma around the reconnection region is heated to coronal temperatures, presumably by slow-mode shocks and Coulomb collisions. These results provide the first direct observational evidence that CMEs reconnect with surrounding magnetic structures, leading to a large-scale reconfiguration of the coronal magnetic field.
KW  - magnetic reconnection
KW  - magnetohydrodynamics (MHD)
KW  - Sun: corona
KW  - Sun: coronal mass ejections (CMEs)
KW  - Sun: magnetic fields
KW  - Sun: UV radiation
Y1  - 2014
U6  - https://doi.org/10.1088/0004-637X/788/1/85
SN  - 0004-637X
SN  - 1538-4357
VL  - 788
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - GEN
A1  - Driel-Gesztelyi, L. van
A1  - Baker, Daniel N.
A1  - Török, Tibor
A1  - Pariat, Etienne
A1  - Green, L. M.
A1  - Williams, D. R.
A1  - Carlyle, J.
A1  - Valori, G.
A1  - Démoulin, Pascal
A1  - Matthews, S. A.
A1  - Kliem, Bernhard
A1  - Malherbe, J.-M.
T1  - Magnetic reconnection driven by filament eruption in the 7 June 2011 event
T2  - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe
N2  - During an unusually massive filament eruption on 7 June 2011, SDO/AIA imaged for the first time significant EUV emission around a magnetic reconnection region in the solar corona. The reconnection occurred between magnetic fields of the laterally expanding CME and a neighbouring active region. A pre-existing quasi-separatrix layer was activated in the process. This scenario is supported by data-constrained numerical simulations of the eruption. Observations show that dense cool filament plasma was re-directed and heated in situ, producing coronal-temperature emission around the reconnection region. These results provide the first direct observational evidence, supported by MHD simulations and magnetic modelling, that a large-scale re-configuration of the coronal magnetic field takes place during solar eruptions via the process of magnetic reconnection.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 608 
KW  - MHD
KW  - instabilities
KW  - Sun: activity
KW  - magnetic fields
KW  - coronal mass ejections (CMEs)
KW  - filaments
KW  - methods: numerical
KW  - data analysis
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415671
IS  - 608
SP  - 502
EP  - 503
ER  - 
TY  - JOUR
A1  - Sackett, Penny D.
A1  - Albrow, Michael D.
A1  - Beaulieu, Jean-Philippe
A1  - Caldwell, John A. R.
A1  - Coutures, C.
A1  - Dominik, M.
A1  - Greenhill, John
A1  - Hill, K.
A1  - Horne, Keith
A1  - Jorgensen, Uffe Grae
A1  - Kane, Stephen R.
A1  - Kubas, Daniel
A1  - Martin, Ralph
A1  - Menzies, J. W.
A1  - Pollard, K. R.
A1  - Sahu, K. C.
A1  - Wambsganß, Joachim
A1  - Watson, R.
A1  - Williams, A.
T1  - PLANET II : a microlensing and transit search for extrasolar planets
N2  - Due to their extremely small luminosity compared to the stars they orbit, planets outside our own Solar System are extraordinarily difficult to detect directly in optical light. Careful photometric monitoring of distant stars, however, can reveal the presence of exoplanets via the microlensing or eclipsing effects they induce. The international PLANET collaboration is performing such monitoring using a cadre of semi-dedicated telescopes around the world. Their results constrain the number of gas giants orbiting 1-7 AU from the most typical stars in the Galaxy. Upgrades in the program are opening regions of ''exoplanet discovery space'' - toward smaller masses and larger orbital radii - that are inaccessible to the Doppler velocity technique.
Y1  - 2003
UR  - http://arxiv.org/pdf/astro-ph/0211098
ER  - 
TY  - JOUR
A1  - Furniss, Amy
A1  - Worseck, Gabor
A1  - Fumagalli, Michele
A1  - Johnson, Caitlin A.
A1  - Williams, David A.
A1  - Pontrelli, P.
A1  - Prochaska, J. Xavier
T1  - Spectroscopic Redshift of the Gamma-Ray Blazar B2 1215+30 from Ly alpha Emission
JF  - The astronomical journal
N2  - We report on Cosmic Origin Spectrograph observations of the gamma-ray bright blazar B2 1215+30, collected in 2015 November. These observations allow for the confirmation of the source redshift from the detection of a Lyα emission feature at λ ~ 1374 Å. The emission feature places the source at a redshift of z = 0.1305 ± 0.003, confirming the source's ground-based spectral measurement. The gamma-ray emission of the source is discussed in the context of the source distance, required for the accurate reconstruction of the intrinsic gamma-ray emission taking the absorption by the extragalactic background light into account. The source distance is found to be low enough that the previously reported detection of an exceptional flaring event from B2 1215+30 in 2014 cannot be used to investigate opacity-specific spectral and variability characteristics introduced by possible ultra-high-energy cosmic-ray propagation.
KW  - galaxies:distances and redshifts
KW  - galaxies: individual (B2 1215+30)
KW  - gamma rays: galaxies
KW  - ultraviolet: galaxies
Y1  - 2019
U6  - https://doi.org/10.3847/1538-3881/aaf28b
SN  - 0004-6256
SN  - 1538-3881
VL  - 157
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Maddock, Simon T.
A1  - Childerstone, Aaron
A1  - Fry, Bryan Grieg
A1  - Williams, David J.
A1  - Barlow, Axel
A1  - Wuester, Wolfgang
T1  - Multi-locus phylogeny and species delimitation of Australo-Papuan blacksnakes (Pseudechis Wagler, 1830: Elapidae: Serpentes)
JF  - Molecular phylogenetics and evolution
N2  - Genetic analyses of Australasian organisms have resulted in the identification of extensive cryptic diversity across the continent. The venomous elapid snakes are among the best-studied organismal groups in this region, but many knowledge gaps persist: for instance, despite their iconic status, the species-level diversity among Australo-Papuan blacksnakes (Pseudechis) has remained poorly understood due to the existence of a group of cryptic species within the P. australis species complex, collectively termed "pygmy mulga snakes". Using two mitochondrial and three nuclear loci we assess species boundaries within the genus using Bayesian species delimitation methods and reconstruct their phylogenetic history using multispecies coalescent approaches. Our analyses support the recognition of 10 species, including all of the currently described pygmy mulga snakes and one undescribed species from the Northern Territory of Australia. Phylogenetic relationships within the genus are broadly consistent with previous work, with the recognition of three major groups, the viviparous red-bellied black snake P. porphyriacus forming the sister species to two clades consisting of ovoviviparous species.
KW  - Australia
KW  - New Guinea
KW  - Molecular phylogenetics
KW  - BPP
KW  - Snakes
KW  - Multispecies coalescent
Y1  - 2017
U6  - https://doi.org/10.1016/j.ympev.2016.09.005
SN  - 1055-7903
SN  - 1095-9513
VL  - 107
SP  - 48
EP  - 55
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Kefi, Sonia
A1  - Berlow, Eric L.
A1  - Wieters, Evie A.
A1  - Navarrete, Sergio A.
A1  - Petchey, Owen L.
A1  - Wood, Spencer A.
A1  - Boit, Alice
A1  - Joppa, Lucas N.
A1  - Lafferty, Kevin D.
A1  - Williams, Richard J.
A1  - Martinez, Neo D.
A1  - Menge, Bruce A.
A1  - Blanchette, Carol A.
A1  - Iles, Alison C.
A1  - Brose, Ulrich
T1  - More than a meal ... integrating non-feeding interactions into food webs
JF  - Ecology letters
N2  - Organisms eating each other are only one of many types of well documented and important interactions among species. Other such types include habitat modification, predator interference and facilitation. However, ecological network research has been typically limited to either pure food webs or to networks of only a few (<3) interaction types. The great diversity of non-trophic interactions observed in nature has been poorly addressed by ecologists and largely excluded from network theory. Herein, we propose a conceptual framework that organises this diversity into three main functional classes defined by how they modify specific parameters in a dynamic food web model. This approach provides a path forward for incorporating non-trophic interactions in traditional food web models and offers a new perspective on tackling ecological complexity that should stimulate both theoretical and empirical approaches to understanding the patterns and dynamics of diverse species interactions in nature.
KW  - Ecological network
KW  - ecosystem engineering
KW  - facilitation
KW  - food web
KW  - interaction modification
KW  - non-trophic interactions
KW  - trophic interactions
Y1  - 2012
U6  - https://doi.org/10.1111/j.1461-0248.2011.01732.x
SN  - 1461-023X
VL  - 15
IS  - 4
SP  - 291
EP  - 300
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Boit, Alice
A1  - Martinez, Neo D.
A1  - Williams, Richard J.
A1  - Gaedke, Ursula
T1  - Mechanistic theory and modelling of complex food-web dynamics in Lake Constance
JF  - Ecology letters
N2  - Mechanistic understanding of consumer-resource dynamics is critical to predicting the effects of global change on ecosystem structure, function and services. Such understanding is severely limited by mechanistic models inability to reproduce the dynamics of multiple populations interacting in the field. We surpass this limitation here by extending general consumer-resource network theory to the complex dynamics of a specific ecosystem comprised by the seasonal biomass and production patterns in a pelagic food web of a large, well-studied lake. We parameterised our allometric trophic network model of 24 guilds and 107 feeding relationships using the lakes food web structure, initial spring biomasses and body-masses. Adding activity respiration, the detrital loop, minimal abiotic forcing, prey resistance and several empirically observed rates substantially increased the model's fit to the observed seasonal dynamics and the size-abundance distribution. This process illuminates a promising approach towards improving food-web theory and dynamic models of specific habitats.
KW  - Allometric Trophic Network model
KW  - community ecology
KW  - food web
KW  - multi-trophic dynamics
KW  - seasonal plankton succession
Y1  - 2012
U6  - https://doi.org/10.1111/j.1461-0248.2012.01777.x
SN  - 1461-023X
VL  - 15
IS  - 6
SP  - 594
EP  - 602
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Richardson, Noel D.
A1  - Shenar, Tomer
A1  - Roy-Loubier, Olivier
A1  - Schaefer, Gail
A1  - Moffat, Anthony F. J.
A1  - St-Louis, Nicole
A1  - Gies, Douglas R.
A1  - Farrington, Chris
A1  - Hill, Grant M.
A1  - Williams, Peredur M.
A1  - Gordon, Kathryn
A1  - Pablo, Herbert
A1  - Ramiaramanantsoa, Tahina
T1  - The CHARA Array resolves the long-period Wolf-Rayet binaries WR 137 and WR 138
JF  - Monthly notices of the Royal Astronomical Society
N2  - We report on interferometric observations with the CHARAArray of two classical Wolf-Rayet (WR) stars in suspected binary systems, namely WR 137 and WR 138. In both cases, we resolve the component stars to be separated by a few milliarcseconds. The data were collected in the H band, and provide a measure of the fractional flux for both stars in each system. We find that the WR star is the dominant H-band light source in both systems (fWR, 137 = 0.59 +/- 0.04; fWR, 138 = 0.67 +/- 0.01), which is confirmed through both comparisons with estimated fundamental parameters for WR stars and O dwarfs, as well as through spectral modelling of each system. Our spectral modelling also provides fundamental parameters for the stars and winds in these systems. The results on WR 138 provide evidence that it is a binary system which may have gone through a previous mass-transfer episode to create the WR star. The separation and position of the stars in the WR 137 system together with previous results from the IOTA interferometer provides evidence that the binary is seen nearly edgeon. The possible edge-on orbit of WR 137 aligns well with the dust production site imaged by the Hubble Space Telescope during a previous periastron passage, showing that the dust production may be concentrated in the orbital plane.
KW  - binaries: visual
KW  - stars: individual: WR 137
KW  - stars: individual: WR 138
KW  - stars: mass-loss
KW  - stars: winds, outflows
KW  - stars: Wolf-Rayet
Y1  - 2016
U6  - https://doi.org/10.1093/mnras/stw1585
SN  - 0035-8711
SN  - 1365-2966
VL  - 461
SP  - 4115
EP  - 4124
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Hommes-Schattmann, Paul J.
A1  - Neffe, Axel T.
A1  - Ahmad, Bilal
A1  - Williams, Gareth R.
A1  - Vanneaux, Valerie
A1  - Menasche, Philippe
A1  - Kalfa, David
A1  - Lendlein, Andreas
T1  - RGD constructs with physical anchor groups as polymer co-electrospinnable cell adhesives
JF  - Polymers for advanced technologies
N2  - The tissue integration of synthetic polymers can be promoted by displaying RGD peptides at the biointerface with the objective of enhancing colonization of the material by endogenous cells. A firm but flexible attachment of the peptide to the polymer matrix, still allowing interaction with receptors, is therefore of interest. Here, the covalent coupling of flexible physical anchor groups, allowing for temporary immobilization on polymeric surfaces via hydrophobic or dipole-dipole interactions, to a RGD peptide was investigated. For this purpose, a stearate or an oligo(ethylene glycol) (OEG) was attached to GRGDS in 51-69% yield. The obtained RGD linker constructs were characterized by NMR, IR and MALDI-ToF mass spectrometry, revealing that the commercially available OEG and stearate linkers are in fact mixtures of similar compounds. The RGD linker constructs were co-electrospun with poly(p-dioxanone) (PPDO). After electrospinning, nitrogen could be detected on the surface of the PPDO fibers by X-ray photoelectron spectroscopy. The nitrogen content exceeded the calculated value for the homogeneous material mixture suggesting a pronounced presentation of the peptide on the fiber surface. Increasing amounts of RGD linker constructs in the electrospinning solution did not lead to a detection of an increased amount of peptide on the scaffold surface, suggesting inhomogeneous distribution of the peptide on the PPDO fiber surface. Human adipose-derived stem cells cultured on the patches showed similar viability as when cultured on PPDO containing pristine RGD. The fully characterized RGD linker constructs could serve as valuable tools for the further development of tissue-integrating polymeric scaffolds. Copyright (c) 2016 John Wiley & Sons, Ltd.
KW  - electrospinning
KW  - RGD peptides
KW  - cell adhesion
KW  - biofunctionalization
Y1  - 2017
U6  - https://doi.org/10.1002/pat.3963
SN  - 1042-7147
SN  - 1099-1581
VL  - 28
SP  - 1312
EP  - 1317
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Gvaramadze, V. V.
A1  - Kniazev, A. Y.
A1  - Miroshnichenko, A. S.
A1  - Berdnikov, Leonid N.
A1  - Langer, N.
A1  - Stringfellow, G. S.
A1  - Todt, Helge Tobias
A1  - Hamann, Wolf-Rainer
A1  - Grebel, E. K.
A1  - Buckley, D.
A1  - Crause, L.
A1  - Crawford, S.
A1  - Gulbis, A.
A1  - Hettlage, C.
A1  - Hooper, E.
A1  - Husser, T. -O.
A1  - Kotze, P.
A1  - Loaring, N.
A1  - Nordsieck, K. H.
A1  - O'Donoghue, D.
A1  - Pickering, T.
A1  - Potter, S.
A1  - Colmenero, E. Romero
A1  - Vaisanen, P.
A1  - Williams, T.
A1  - Wolf, M.
A1  - Reichart, D. E.
A1  - Ivarsen, K. M.
A1  - Haislip, J. B.
A1  - Nysewander, M. C.
A1  - LaCluyze, A. P.
T1  - Discovery of two new Galactic candidate luminous blue variables with Wide-field Infrared Survey Explorer
JF  - Monthly notices of the Royal Astronomical Society
N2  - We report the discovery of two new Galactic candidate luminous blue variable (LBV) stars via detection of circular shells (typical of confirmed and candidate LBVs) and follow-up spectroscopy of their central stars. The shells were detected at 22 mu m in the archival data of the Mid-Infrared All Sky Survey carried out with the Wide-field Infrared Survey Explorer (WISE). Follow-up optical spectroscopy of the central stars of the shells conducted with the renewed Southern African Large Telescope (SALT) showed that their spectra are very similar to those of the well-known LBVs P Cygni and AG Car, and the recently discovered candidate LBV MN112, which implies the LBV classification for these stars as well. The LBV classification of both stars is supported by detection of their significant photometric variability: one of them brightened in the R and I bands by 0.68 +/- 0.10 and 0.61 +/- 0.04 mag, respectively, during the last 1318 years, while the second one (known as Hen 3-1383) varies its B, V, R, I and Ks brightnesses by similar or equal to 0.50.9 mag on time-scales from 10 d to decades. We also found significant changes in the spectrum of Hen 3-1383 on a time-scale of similar or equal to 3 months, which provides additional support for the LBV classification of this star. Further spectrophotometric monitoring of both stars is required to firmly prove their LBV status. We discuss a connection between the location of massive stars in the field and their fast rotation, and suggest that the LBV activity of the newly discovered candidate LBVs might be directly related to their possible runaway status.
KW  - line: identification
KW  - circumstellar matter
KW  - stars: emission-line, Be
KW  - stars: evolution
KW  - stars: individual: Hen 3-1383
KW  - stars: massive
Y1  - 2012
U6  - https://doi.org/10.1111/j.1365-2966.2012.20556.x
SN  - 0035-8711
VL  - 421
IS  - 4
SP  - 3325
EP  - 3337
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Lützow, Karola
A1  - Hommes-Schattmann, Paul J.
A1  - Neffe, Axel T.
A1  - Ahmad, Bilal
A1  - Williams, Gareth R.
A1  - Lendlein, Andreas
T1  - Perfluorophenyl azide functionalization of electrospun poly(para-dioxanone)
JF  - Polymers for advanced technologies
N2  - Strategies to surface-functionalize scaffolds by covalent binding of biologically active compounds are of fundamental interest to control the interactions between scaffolds and biomolecules or cells. Poly(para-dioxanone) (PPDO) is a clinically established polymer that has shown potential as temporary implant, eg, for the reconstruction of the inferior vena cava, as a nonwoven fiber mesh. However, PPDO lacks suitable chemical groups for covalent functionalization. Furthermore, PPDO is highly sensitive to hydrolysis, reflected by short in vivo half-life times and degradation during storage. Establishing a method for covalent functionalization without degradation of this hydrolyzable polymer is therefore important to enable the surface tailoring for tissue engineering applications. It was hypothesized that treatment of PPDO with an N-hydroxysuccinimide ester group bearing perfluorophenyl azide (PFPA) under UV irradiation would allow efficient surface functionalization of the scaffold. X-ray photoelectron spectroscopy and attenuated total reflectance Fourier-transformed infrared spectroscopy investigation revealed the successful binding, while a gel permeation chromatography study showed that degradation did not occur under these conditions. Coupling of a rhodamine dye to the N-hydroxysuccinimide esters on the surface of a PFPA-functionalized scaffold via its amine linker showed a homogenous staining of the PPDO in laser confocal microscopy. The PFPA method is therefore applicable even to the surface functionalization of hydrolytically labile polymers, and it was demonstrated that PFPA chemistry may serve as a versatile tool for the (bio-)functionalization of PPDO scaffolds.
KW  - biological applications of polymers
KW  - fibers
KW  - functionalization of polymers
KW  - microstructure
Y1  - 2018
U6  - https://doi.org/10.1002/pat.4331
SN  - 1042-7147
SN  - 1099-1581
VL  - 30
IS  - 5
SP  - 1165
EP  - 1172
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Thiede, Rasmus Christoph
A1  - Arrowsmith, J. Ramón
A1  - Bookhagen, Bodo
A1  - McWilliams, Michael O.
A1  - Sobel, Edward
A1  - Strecker, Manfred
T1  - Dome formation and extension in the Tethyan Himalaya, Leo Pargil, northwest India
N2  - Metamorphic dome complexes occur within the internal structures of the northern Himalaya and southern Tibet. Their origin, deformation, and fault displacement patterns are poorly constrained. We report new field mapping, structural data, and cooling ages from the western flank of the Leo Pargil dome in the northwestern Himalaya in an attempt to characterize its post-middle Miocene structural development. The western flank of the dome is characterized by shallow, west-dipping pervasive foliation and WNW-ESE mineral lineation. Shear-sense indicators demonstrate that it is affected by east-west normal faulting that facilitated exhumation of high-grade metamorphic rocks in a contractional setting. Sustained top-to-northwest normal faulting during exhumation is observed in a progressive transition from ductile to brittle deformation. Garnet and kyanite indicate that the Leo Pargil dome was exhumed from the mid-crust. Ar- 40/Ar-39 mica and apatite fission track (AFT) ages constrain cooling and exhumation pathways front 350 to 60 degrees C and suggest that the dome cooled in three stages since the middle Miocene. Ar-40/Ar-39 white mica ages of 16-14 Ma suggest a first phase of rapid cooling and provide minimum estimates for the onset of dome exhumation. AFT ages between 10 and 8 Ma suggest that ductile fault displacement had ceased by then, and AFT track-length data from high-elevation samples indicate that the rate of cooling had decreased significantly. We interpret this to indicate decreased fault displacement along the Leo Pargil shear zone and possibly a transition to the Kaurik-Chango normal fault system between 10 and 6 Ma. AFT ages from lower elevations indicate accelerated cooling since the Pliocene that cannot be related to pure fault displacement, and therefore may reflect more pronounced regionally distributed and erosion-driven exhumation
Y1  - 2006
U6  - https://doi.org/10.1130/B25872.1
ER  - 
TY  - JOUR
A1  - Thiede, Rasmus Christoph
A1  - Arrowsmith, J. Ramón
A1  - Bookhagen, Bodo
A1  - McWilliams, Michael O.
A1  - Sobel, Edward
A1  - Strecker, Manfred
T1  - From tectonically to erosionally controlled development of the Himalayan orogen
N2  - Whether variations in the spatial distribution of erosion influence the location, style, and magnitude of deformation within the Himalayan orogen is a matter of debate. We report new Ar-40/Ar-39 white mica and apatite fission- track (AFT) ages that measure the vertical component of exhumation rates along an similar to 120-km-wide NE-SW transect spanning the greater Sutlej region of northwest India. The Ar-40/Ar-39 data indicate that first the High Himalayan Crystalline units cooled below their closing temperature during the early to middle Miocene. Subsequently, Lesser Himalayan Crystalline nappes cooled rapidly, indicating southward propagation of the orogen during late Miocene to Pliocene time. The AFT data, in contrast, imply synchronous exhumation of a NE-SW-oriented similar to 80 x 40 km region spanning both crystalline nappes during the Pliocene-Quaternary. The locus of pronounced exhumation defined by the AFT data correlates with a region of high precipitation, discharge, and sediment flux rates during the Holocene. This correlation suggests that although tectonic processes exerted the dominant control on the denudation pattern before and until the middle Miocene; erosion may have been the most important factor since the Pliocene
Y1  - 2005
SN  - 0091-7613
ER  - 
TY  - JOUR
A1  - Hoke, Gregory D.
A1  - Garzione, Carmala N.
A1  - Araneo, Diego C.
A1  - Latorre, Claudio
A1  - Strecker, Manfred
A1  - Williams, Kendra J.
T1  - The stable isotope altimeter : do quaternary pedogenic carbonates predict modern elevations?
N2  - Stable isotope altimetry is a useful tool for estimating paleoelevation in sedimentary records. Yet questions remain regarding how source moisture, climate, and local topography can influence these estimates. Here we present stable isotope altimetry results on late Quaternary pedogenic carbonates of known elevation on both flanks of the Andean orogen at 33 degrees S. We measured delta O-18 values of pedogenic carbonates and river water samples from small drainages at regular elevation increments within the Rio Aconcagua (Chile) and Rio Mendoza (Argentina) catchments. The delta O-18 values of river waters correlate well with elevation and show similar isotopic gradients between the Chilean (-3.7 parts per thousand/km) and Argentine (-4.8 parts per thousand/km) sides of the range. Uncertainties associated with scatter in the river water data and assumptions about the temperature of carbonate formation indicate that elevation estimates have 1 sigma errors of 350-450 m. We estimate the isotopic composition of soil water from pedogenic carbonates on both sides of the range by assuming mean annual temperatures based the modern temperature lapse rate from meteorological station data. Combined, our data show that stable isotope altimetry produces reasonable estimates of modern elevation, with the majority of our samples (60%) within the 1 sigma uncertainties and 77% within 2 sigma.
Y1  - 2009
UR  - http://geology.gsapubs.org/
U6  - https://doi.org/10.1130/G30308a.1
SN  - 0091-7613
ER  -