TY  - THES
A1  - Foster, Mary Grace
T1  - X-Ray studies of exoplanet systems
N2  - X-rays are integral to furthering our knowledge of exoplanetary systems. In this work we discuss the use of X-ray observations to understand star-planet interac- tions, mass-loss rates of an exoplanet’s atmosphere and the study of an exoplanet’s atmospheric components using future X-ray spectroscopy.
The low-mass star GJ 1151 was reported to display variable low-frequency radio emission, which is an indication of coronal star-planet interactions with an unseen exoplanet. In chapter 5 we report the first X-ray detection of GJ 1151’s corona based on XMM-Newton data. Averaged over the observation, we detect the star with a low coronal temperature of 1.6 MK and an X-ray luminosity of LX = 5.5 × 1026 erg/s. This is compatible with the coronal assumptions for a sub-Alfvénic star- planet interaction origin of the observed radio signals from this star.
In chapter 6, we aim to characterise the high-energy environment of known ex- oplanets and estimate their mass-loss rates. This work is based on the soft X-ray instrument on board the Spectrum Roentgen Gamma (SRG) mission, eROSITA, along with archival data from ROSAT, XMM-Newton, and Chandra. We use these four X-ray source catalogues to derive X-ray luminosities of exoplanet host stars in the 0.2-2 keV energy band. A catalogue of the mass-loss rates of 287 exoplan- ets is presented, with 96 of these planets characterised for the first time using new eROSITA detections. Of these first time detections, 14 are of transiting exoplanets that undergo irradiation from their host stars that is of a level known to cause ob- servable evaporation signals in other systems, making them suitable for follow-up observations.
In the next generation of space observatories, X-ray transmission spectroscopy of an exoplanet’s atmosphere will be possible, allowing for a detailed look into the atmospheric composition of these planets. In chapter 7, we model sample spectra using a toy model of an exoplanetary atmosphere to predict what exoplanet transit observations with future X-ray missions such as Athena will look like. We then estimate the observable X-ray transmission spectrum for a typical Hot Jupiter-type exoplanet, giving us insights into the advances in X-ray observations of exoplanets in the decades to come.
N2  - Röntgenstrahlen sind ein wesentlicher Bestandteil, um unser Wissen über extrasolare Planetensysteme zu vertiefen und zu erweitern. In dieser Arbeit erörtern wir den Einsatz von Röntgenbeobachtungen zum Verständnis von Stern-Planeten-Interaktionen, der Abschätzung von Massenverlustraten von Exoplanetenatmosphären und die Untersuchung der atmosphärischen Komponenten eines Exoplaneten mithilfe zukünftiger Röntgenspektroskopie.

Beobachtungen des massearmen Sterns GJ 1151 deuten auf eine variable Emission niederfrequenter Radiostrahlung hin, was als Indiz für koronale Stern-Planeten-Wechselwirkungen mit einem unsichtbaren Exoplaneten angesehen wird. In Kapitel 5 berichten wir über den ersten Röntgennachweis der Korona von GJ 1151, basierend auf XMM-Newton Daten. Über die gesamte Beobachtungsdauer gemittelt, weisen wir den Stern mit einer niedrigen koronalen Temperatur von 1,6 MK und einer Röntgenluminosität von LX = 5, 5 ◊ 1026 erg/s nach. Dieser Nachweis im Röntgenlicht ist kompatibel mit der Annahme, dass sub-Alfvénische Wechselwirkungen zwischen stellarer Corona und Exoplanet die Ursache für die beobachteten Radiosignale des Sterns sind.

Kapitel 6 zielt darauf ab, die hochenergetische Umgebung bekannter Exoplaneten zu charakterisieren und die Massenverlustraten der Planetenatmosphären abzuschätzen. Diese Arbeit basiert auf neu gewonnenen Daten des Instruments für weiche Röntgenstrahlung an Bord der Spectrum Roentgen Gamma (SRG) Mission, eROSITA, und wird komplementiert von Archivdaten von ROSAT, XMM-Newton und Chandra. Mithilfe dieser vier Röntgenquellenkataloge vermessen wir die Röntgenhelligkeit der Zentralsterne von bekannten Exoplanetensytemen im Energiebereich von 0,2-2 keV. Die Ergebnisse sind zusammen mit den errechneten Massenverlustraten von 287 Exoplaneten in einem Katalog zusammengefasst, darunter 96 Planeten, die zum ersten Mal durch neue eROSITA-Nachweise charakterisiert wurden. Bei 14 dieser Erstnachweise handelt es sich um transitierende Exoplaneten, die von ihrem Heimatstern so stark bestrahlt werden, dass beobachtbare Signale, ausgelöst durch die Verdampfung ihrer Atmosphäre, zu erwarten sind. Speziell diese Systeme eignen sich besonders für Folgebeobachtungen.

Mit der nächsten Generation von Weltraumobservatorien wird die Röntgentransmissionsspektroskopie von extrasolaren Planetenatmosphären möglich sein, was nie dagewesene Details über die atmosphärische Zusammensetzung dieser Planeten ans Licht bringen wird. In Kapitel 7 modellieren wir Transmissionsspektren mithilfe eines vereinfachten Modells einer Exoplanetenatmosphäre um vorherzusagen, wie Transitbeobachtungen von Exoplaneten mit zukünftigen Röntgenmissionen wie Athena aussehen werden. Wir schätzen dann das beobachtbare Röntgentransmissionsspektrum für einen typischen Exoplaneten vom Typ Hot Jupiter ab, was uns einen Einblick in die zu erwartenden Fortschritte bei der Röntgenbeobachtung von Exoplaneten in den kommenden Jahrzehnten gibt.
KW  - exoplanets
KW  - x-rays
KW  - stellar physics
KW  - Exoplaneten
KW  - Röntgenstrahlen
KW  - stellare Physik
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-562152
PB  - xiii, 92
ER  - 
TY  - JOUR
A1  - Aarts, Alexander A.
A1  - Anderson, Joanna E.
A1  - Anderson, Christopher J.
A1  - Attridge, Peter R.
A1  - Attwood, Angela
A1  - Axt, Jordan
A1  - Babel, Molly
A1  - Bahnik, Stepan
A1  - Baranski, Erica
A1  - Barnett-Cowan, Michael
A1  - Bartmess, Elizabeth
A1  - Beer, Jennifer
A1  - Bell, Raoul
A1  - Bentley, Heather
A1  - Beyan, Leah
A1  - Binion, Grace
A1  - Borsboom, Denny
A1  - Bosch, Annick
A1  - Bosco, Frank A.
A1  - Bowman, Sara D.
A1  - Brandt, Mark J.
A1  - Braswell, Erin
A1  - Brohmer, Hilmar
A1  - Brown, Benjamin T.
A1  - Brown, Kristina
A1  - Bruening, Jovita
A1  - Calhoun-Sauls, Ann
A1  - Callahan, Shannon P.
A1  - Chagnon, Elizabeth
A1  - Chandler, Jesse
A1  - Chartier, Christopher R.
A1  - Cheung, Felix
A1  - Christopherson, Cody D.
A1  - Cillessen, Linda
A1  - Clay, Russ
A1  - Cleary, Hayley
A1  - Cloud, Mark D.
A1  - Cohn, Michael
A1  - Cohoon, Johanna
A1  - Columbus, Simon
A1  - Cordes, Andreas
A1  - Costantini, Giulio
A1  - Alvarez, Leslie D. Cramblet
A1  - Cremata, Ed
A1  - Crusius, Jan
A1  - DeCoster, Jamie
A1  - DeGaetano, Michelle A.
A1  - Della Penna, Nicolas
A1  - den Bezemer, Bobby
A1  - Deserno, Marie K.
A1  - Devitt, Olivia
A1  - Dewitte, Laura
A1  - Dobolyi, David G.
A1  - Dodson, Geneva T.
A1  - Donnellan, M. Brent
A1  - Donohue, Ryan
A1  - Dore, Rebecca A.
A1  - Dorrough, Angela
A1  - Dreber, Anna
A1  - Dugas, Michelle
A1  - Dunn, Elizabeth W.
A1  - Easey, Kayleigh
A1  - Eboigbe, Sylvia
A1  - Eggleston, Casey
A1  - Embley, Jo
A1  - Epskamp, Sacha
A1  - Errington, Timothy M.
A1  - Estel, Vivien
A1  - Farach, Frank J.
A1  - Feather, Jenelle
A1  - Fedor, Anna
A1  - Fernandez-Castilla, Belen
A1  - Fiedler, Susann
A1  - Field, James G.
A1  - Fitneva, Stanka A.
A1  - Flagan, Taru
A1  - Forest, Amanda L.
A1  - Forsell, Eskil
A1  - Foster, Joshua D.
A1  - Frank, Michael C.
A1  - Frazier, Rebecca S.
A1  - Fuchs, Heather
A1  - Gable, Philip
A1  - Galak, Jeff
A1  - Galliani, Elisa Maria
A1  - Gampa, Anup
A1  - Garcia, Sara
A1  - Gazarian, Douglas
A1  - Gilbert, Elizabeth
A1  - Giner-Sorolla, Roger
A1  - Glöckner, Andreas
A1  - Göllner, Lars
A1  - Goh, Jin X.
A1  - Goldberg, Rebecca
A1  - Goodbourn, Patrick T.
A1  - Gordon-McKeon, Shauna
A1  - Gorges, Bryan
A1  - Gorges, Jessie
A1  - Goss, Justin
A1  - Graham, Jesse
A1  - Grange, James A.
A1  - Gray, Jeremy
A1  - Hartgerink, Chris
A1  - Hartshorne, Joshua
A1  - Hasselman, Fred
A1  - Hayes, Timothy
A1  - Heikensten, Emma
A1  - Henninger, Felix
A1  - Hodsoll, John
A1  - Holubar, Taylor
A1  - Hoogendoorn, Gea
A1  - Humphries, Denise J.
A1  - Hung, Cathy O. -Y.
A1  - Immelman, Nathali
A1  - Irsik, Vanessa C.
A1  - Jahn, Georg
A1  - Jaekel, Frank
A1  - Jekel, Marc
A1  - Johannesson, Magnus
A1  - Johnson, Larissa G.
A1  - Johnson, David J.
A1  - Johnson, Kate M.
A1  - Johnston, William J.
A1  - Jonas, Kai
A1  - Joy-Gaba, Jennifer A.
A1  - Kappes, Heather Barry
A1  - Kelso, Kim
A1  - Kidwell, Mallory C.
A1  - Kim, Seung Kyung
A1  - Kirkhart, Matthew
A1  - Kleinberg, Bennett
A1  - Knezevic, Goran
A1  - Kolorz, Franziska Maria
A1  - Kossakowski, Jolanda J.
A1  - Krause, Robert Wilhelm
A1  - Krijnen, Job
A1  - Kuhlmann, Tim
A1  - Kunkels, Yoram K.
A1  - Kyc, Megan M.
A1  - Lai, Calvin K.
A1  - Laique, Aamir
A1  - Lakens, Daniel
A1  - Lane, Kristin A.
A1  - Lassetter, Bethany
A1  - Lazarevic, Ljiljana B.
A1  - LeBel, Etienne P.
A1  - Lee, Key Jung
A1  - Lee, Minha
A1  - Lemm, Kristi
A1  - Levitan, Carmel A.
A1  - Lewis, Melissa
A1  - Lin, Lin
A1  - Lin, Stephanie
A1  - Lippold, Matthias
A1  - Loureiro, Darren
A1  - Luteijn, Ilse
A1  - Mackinnon, Sean
A1  - Mainard, Heather N.
A1  - Marigold, Denise C.
A1  - Martin, Daniel P.
A1  - Martinez, Tylar
A1  - Masicampo, E. J.
A1  - Matacotta, Josh
A1  - Mathur, Maya
A1  - May, Michael
A1  - Mechin, Nicole
A1  - Mehta, Pranjal
A1  - Meixner, Johannes
A1  - Melinger, Alissa
A1  - Miller, Jeremy K.
A1  - Miller, Mallorie
A1  - Moore, Katherine
A1  - Möschl, Marcus
A1  - Motyl, Matt
A1  - Müller, Stephanie M.
A1  - Munafo, Marcus
A1  - Neijenhuijs, Koen I.
A1  - Nervi, Taylor
A1  - Nicolas, Gandalf
A1  - Nilsonne, Gustav
A1  - Nosek, Brian A.
A1  - Nuijten, Michele B.
A1  - Olsson, Catherine
A1  - Osborne, Colleen
A1  - Ostkamp, Lutz
A1  - Pavel, Misha
A1  - Penton-Voak, Ian S.
A1  - Perna, Olivia
A1  - Pernet, Cyril
A1  - Perugini, Marco
A1  - Pipitone, R. Nathan
A1  - Pitts, Michael
A1  - Plessow, Franziska
A1  - Prenoveau, Jason M.
A1  - Rahal, Rima-Maria
A1  - Ratliff, Kate A.
A1  - Reinhard, David
A1  - Renkewitz, Frank
A1  - Ricker, Ashley A.
A1  - Rigney, Anastasia
A1  - Rivers, Andrew M.
A1  - Roebke, Mark
A1  - Rutchick, Abraham M.
A1  - Ryan, Robert S.
A1  - Sahin, Onur
A1  - Saide, Anondah
A1  - Sandstrom, Gillian M.
A1  - Santos, David
A1  - Saxe, Rebecca
A1  - Schlegelmilch, Rene
A1  - Schmidt, Kathleen
A1  - Scholz, Sabine
A1  - Seibel, Larissa
A1  - Selterman, Dylan Faulkner
A1  - Shaki, Samuel
A1  - Simpson, William B.
A1  - Sinclair, H. Colleen
A1  - Skorinko, Jeanine L. M.
A1  - Slowik, Agnieszka
A1  - Snyder, Joel S.
A1  - Soderberg, Courtney
A1  - Sonnleitner, Carina
A1  - Spencer, Nick
A1  - Spies, Jeffrey R.
A1  - Steegen, Sara
A1  - Stieger, Stefan
A1  - Strohminger, Nina
A1  - Sullivan, Gavin B.
A1  - Talhelm, Thomas
A1  - Tapia, Megan
A1  - te Dorsthorst, Anniek
A1  - Thomae, Manuela
A1  - Thomas, Sarah L.
A1  - Tio, Pia
A1  - Traets, Frits
A1  - Tsang, Steve
A1  - Tuerlinckx, Francis
A1  - Turchan, Paul
A1  - Valasek, Milan
A1  - Van Aert, Robbie
A1  - van Assen, Marcel
A1  - van Bork, Riet
A1  - van de Ven, Mathijs
A1  - van den Bergh, Don
A1  - van der Hulst, Marije
A1  - van Dooren, Roel
A1  - van Doorn, Johnny
A1  - van Renswoude, Daan R.
A1  - van Rijn, Hedderik
A1  - Vanpaemel, Wolf
A1  - Echeverria, Alejandro Vasquez
A1  - Vazquez, Melissa
A1  - Velez, Natalia
A1  - Vermue, Marieke
A1  - Verschoor, Mark
A1  - Vianello, Michelangelo
A1  - Voracek, Martin
A1  - Vuu, Gina
A1  - Wagenmakers, Eric-Jan
A1  - Weerdmeester, Joanneke
A1  - Welsh, Ashlee
A1  - Westgate, Erin C.
A1  - Wissink, Joeri
A1  - Wood, Michael
A1  - Woods, Andy
A1  - Wright, Emily
A1  - Wu, Sining
A1  - Zeelenberg, Marcel
A1  - Zuni, Kellylynn
T1  - Estimating the reproducibility of psychological science
JF  - Science
N2  - Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams.
Y1  - 2015
U6  - https://doi.org/10.1126/science.aac4716
SN  - 1095-9203
SN  - 0036-8075
VL  - 349
IS  - 6251
PB  - American Assoc. for the Advancement of Science
CY  - Washington
ER  - 
TY  - JOUR
A1  - Foster, Mary Grace
A1  - Poppenhäger, Katja
A1  - Ilić Petković, Nikoleta
A1  - Schwope, Axel
T1  - Exoplanet X-ray irradiation and evaporation rates with eROSITA
JF  - Astronomy and astrophysics : an international weekly journal
N2  - High-energy irradiation is a driver for atmospheric evaporation and mass loss in exoplanets. This work is based on data from eROSITA, the soft X-ray instrument on board the Spectrum Roentgen Gamma mission, as well as on archival data from other missions. We aim to characterise the high-energy environment of known exoplanets and estimate their mass-loss rates. We use X-ray source catalogues from eROSITA, XMM-Newton, Chandra, and ROSAT to derive X-ray luminosities of exoplanet host stars in the 0.2–2 keV energy band with an underlying coronal, that is, optically thin thermal spectrum. We present a catalogue of stellar X-ray and EUV luminosities, exoplanetary X-ray and EUV irradiation fluxes, and estimated mass-loss rates for a total of 287 exoplanets, 96 of which are characterised for the first time based on new eROSITA detections. We identify 14 first-time X-ray detections of transiting exoplanets that are subject to irradiation levels known to cause observable evaporation signatures in other exoplanets. This makes them suitable targets for follow-up observations.
KW  - stars: coronae
KW  - stars: activity
KW  - planet-star interactions
KW  - planets and
KW  - satellites: atmospheres
KW  - X-rays: stars
Y1  - 2022
U6  - https://doi.org/10.1051/0004-6361/202141097
SN  - 0004-6361
SN  - 1432-0746
VL  - 661
PB  - EDP Sciences
CY  - Les Ulis
ER  - 
TY  - JOUR
A1  - Foster, Grace
A1  - Poppenhäger, Katja
T1  - Identifying interesting planetary systems for future X-ray observations
JF  - Astronomische Nachrichten = Astronomical notes
N2  - X-ray observations of star-planet systems are important to grow our understanding of exoplanets; these observations allow for studies of photoevaporation of the exoplanetary atmosphere, and in some cases even estimations of the size of the outer planetary atmosphere. The German-Russian eROSITA instrument onboard the SRG (Spectrum Roentgen Gamma) mission is performing the first all-sky X-ray survey since the 1990s, and provides X-ray fluxes and spectra of exoplanet host stars over a much larger volume than was accessible before. Using new eROSITA data as well as archival data from XMM-Newton, Chandra, and ROSAT, we estimate mass-loss rates of exoplanets under an energy-limited escape scenario and identify several exoplanets with strong X-ray irradiation and expected mass loss that are amenable to follow-up observations at other wavelengths. We model sample spectra using a toy model of an exoplanetary atmosphere to predict what exoplanet transit observations with future X-ray missions such as Athena will look like and estimate the observable X-ray transmission spectrum for a typical hot Jupiter-type exoplanet.
KW  - planets and satellites
KW  - general
KW  - stars
KW  - activity
KW  - coronae
KW  - planetary systems
KW  - X-rays
Y1  - 2022
U6  - https://doi.org/10.1002/asna.20220007
SN  - 1521-3994
VL  - 343
IS  - 4
PB  - Wiley-VCH
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Foster, Mary Grace
A1  - Poppenhäger, Katja
A1  - Alvarado-Gómez, Julián David
A1  - Schmitt, Jürgen
T1  - The corona of GJ 1151 in the context of star-planet interaction
JF  - Monthly notices of the Royal Astronomical Society
N2  - The low-mass star GJ 1151 has been reported to display variable low-frequency radio emission, which has been interpreted as a signpost of coronal star-planet interactions with an unseen exoplanet. Here we report the first X-ray detection of GJ 1151's corona based on the XMM-Newton data. We find that the star displays a small flare during the X-ray observation. Averaged over the observation, we detect the star with a low coronal temperature of 1.6 MK and an X-ray luminosity of L-X = 5.5 x 10(26) erg s(-1). During the quiescent time periods excluding the flare, the star remains undetected with an upper limit of L-X,L- qui <= 3.7 x 10(26) erg s(-1). This is compatible with the coronal assumptions used in a recently published model for a star-planet interaction origin of the observed radio signals from this star.
KW  - planet
KW  - star interactions
KW  - stars: coronae
KW  - X-rays: individual: GJ 1151
Y1  - 2020
U6  - https://doi.org/10.1093/mnras/staa1982
SN  - 0035-8711
SN  - 1365-2966
VL  - 497
IS  - 1
SP  - 1015
EP  - 1019
PB  - Oxford Univ. Press
CY  - Oxford
ER  -