TY  - JOUR
A1  - Townsley, Leisa K.
A1  - Broos, Patrick S.
A1  - Corcoran, Michael F.
A1  - Feigelson, Eric D.
A1  - Gagne, Marc
A1  - Montmerle, Thierry
A1  - Oey, M. S.
A1  - Smith, Nathan
A1  - Garmire, Gordon P.
A1  - Getman, Konstantin V.
A1  - Povich, Matthew S.
A1  - Evans, Nancy Remage
A1  - Naze, Yael
A1  - Parkin, E. R.
A1  - Preibisch, Thomas
A1  - Wang, Junfeng
A1  - Wou, Scott J.
A1  - Chu, You-Hua
A1  - Cohen, David H.
A1  - Gruendl, Robert A.
A1  - Hamaguchi, Kenji
A1  - King, Robert R.
A1  - Mac Low, Mordecai-Mark
A1  - McCaughrean, Mark J.
A1  - Moffat, Anthony F. J.
A1  - Oskinova, Lida
A1  - Pittard, Julian M.
A1  - Stassun, Keivan G.
A1  - Ud-Doula, Asif
A1  - Walborn, Nolan R.
A1  - Waldron, Wayne L.
A1  - Churchwell, Ed
A1  - Nictiols, J. S.
A1  - Owocki, Stanley P.
A1  - Schulz, Norbert S.
T1  - An introduction to the chandra carina complex project
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Supplement series
N2  - The Great Nebula in Carina provides an exceptional view into the violent massive star formation and feedback that typifies giant H II regions and starburst galaxies. We have mapped the Carina star-forming complex in X-rays, using archival Chandra data and a mosaic of 20 new 60 ks pointings using the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer, as a testbed for understanding recent and ongoing star formation and to probe Carina's regions of bright diffuse X-ray emission. This study has yielded a catalog of properties of > 14,000 X-ray point sources;> 9800 of them have multiwavelength counterparts. Using Chandra's unsurpassed X-ray spatial resolution, we have separated these point sources from the extensive, spatially-complex diffuse emission that pervades the region; X-ray properties of this diffuse emission suggest that it traces feedback from Carina's massive stars. In this introductory paper, we motivate the survey design, describe the Chandra observations, and present some simple results, providing a foundation for the 15 papers that follow in this special issue and that present detailed catalogs, methods, and science results.
KW  - H II regions
KW  - stars: massive
KW  - stars: pre-main sequence
KW  - X-rays: individual (Carina)
KW  - X-rays: ISM
KW  - X-rays: stars
Y1  - 2011
U6  - https://doi.org/10.1088/0067-0049/194/1/1
SN  - 0067-0049
VL  - 194
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Oskinova, Lida
A1  - Hamann, Wolf-Rainer
A1  - Feldmeier, Achim
A1  - Ignace, Richard
A1  - Chu, You-Hua
T1  - Discovery of X-ray emission from the Wolf-Rayet star WR 142 of oxygen subtype
N2  - We report the discovery of weak yet hard X-ray emission from the Wolf-Rayet (WR) star WR 142 with the XMM- Newton X-ray telescope. Being of spectral subtype WO2, WR 142 is a massive star in a very advanced evolutionary stage shortly before its explosion as a supernova or. gamma-ray burst. This is the first detection of X-ray emission from a WO- type star. We rule out any serendipitous X-ray sources within approximate to 1 '' of WR 142. WR 142 has an X- ray luminosity of L-X approximate to 7 x 10(30) erg s(-1), which constitutes only less than or similar to 10(-8) of its bolometric luminosity. The hard X-ray spectrum suggests a plasma temperature of about 100 MK. Commonly, X-ray emission from stellar winds is attributed to embedded shocks due to the intrinsic instability of the radiation driving. From qualitative considerations we conclude that this mechanism cannot account for the hardness of the observed radiation. There are no hints for a binary companion. Therefore the only remaining, albeit speculative explanation must refer to magnetic activity. Possibly related, WR 142 seems to rotate extremely fast, as indicated by the unusually round profiles of its optical emission lines. Our detection implies that the wind of WR 142 must be relatively transparent to X-rays, which can be due to strong wind ionization, wind clumping, or nonspherical geometry from rapid rotation.
Y1  - 2009
UR  - http://iopscience.iop.org/0004-637X/
U6  - https://doi.org/10.1088/0004-637x/693/1/L44
SN  - 0004-637X
ER  - 
TY  - GEN
A1  - Oskinova, Lida
A1  - Guerrero, Martín A.
A1  - Hénault-Brunet, Vincent
A1  - Sun, W.
A1  - Chu, You-Hua
A1  - Evans, Chris
A1  - Gallagher, John S.
A1  - Gruendl, Robert A.
A1  - Reyes-Iturbide, Jorge
T1  - The slow X-ray pulsar SXP 1062 and associated supernova remnant in the Wing of the Small Magellanic Cloud
T2  - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe
N2  - SXP 1062 is an exceptional case of a young neutron star in a wind-fed high-mass X-ray binary associated with a supernova remnant. A unique combination of measured spin period, its derivative, luminosity and young age makes this source a key probe for the physics of accretion and neutron star evolution. Theoretical models proposed to explain the properties of SXP 1062 shall be tested with new data.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 591 
KW  - stars: emission-line
KW  - Be
KW  - X-rays: binaries
KW  - pulsars: individual (SXP 1062)
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415135
SN  - 1866-8372
IS  - 591
ER  - 
TY  - JOUR
A1  - Nidever, David L.
A1  - Olsen, Knut
A1  - Walker, Alistair R.
A1  - Katherina Vivas, A.
A1  - Blum, Robert D.
A1  - Kaleida, Catherine
A1  - Choi, Yumi
A1  - Conn, Blair C.
A1  - Gruendl, Robert A.
A1  - Bell, Eric F.
A1  - Besla, Gurtina
A1  - Munoz, Ricardo R.
A1  - Gallart, Carme
A1  - Martin, Nicolas F.
A1  - Olszewski, Edward W.
A1  - Saha, Abhijit
A1  - Monachesi, Antonela
A1  - Monelli, Matteo
A1  - de Boer, Thomas J. L.
A1  - Johnson, L. Clifton
A1  - Zaritsky, Dennis
A1  - Stringfellow, Guy S.
A1  - van der Marel, Roeland P.
A1  - Cioni, Maria-Rosa L.
A1  - Jin, Shoko
A1  - Majewski, Steven R.
A1  - Martinez-Delgado, David
A1  - Monteagudo, Lara
A1  - Noel, Noelia E. D.
A1  - Bernard, Edouard J.
A1  - Kunder, Andrea
A1  - Chu, You-Hua
A1  - Bell, Cameron P. M.
A1  - Santana, Felipe
A1  - Frechem, Joshua
A1  - Medina, Gustavo E.
A1  - Parkash, Vaishali
A1  - Seron Navarrete, J. C.
A1  - Hayes, Christian
T1  - SMASH: Survey of the MAgellanic Stellar History
JF  - The astronomical journal
N2  - The Large and Small Magellanic Clouds are unique local laboratories for studying the formation and evolution of small galaxies in exquisite detail. The Survey of the MAgellanic Stellar History (SMASH) is an NOAO community Dark Energy Camera (DECam) survey of the Clouds mapping 480 deg2 (distributed over similar to 2400 square degrees at similar to 20% filling factor) to similar to 24th. mag in ugriz. The primary goals of SMASH are to identify low surface brightness stellar populations associated with the stellar halos and tidal debris of the Clouds, and to derive spatially resolved star formation histories. Here, we present a summary of the survey, its data reduction, and a description of the first public Data Release (DR1). The SMASH DECam data have been reduced with a combination of the NOAO Community Pipeline, the PHOTRED automated point-spread-function photometry pipeline, and custom calibration software. The astrometric precision is similar to 15 mas and the accuracy is similar to 2 mas with respect to the Gaia reference frame. The photometric precision is similar to 0.5%-0.7% in griz and similar to 1% in u with a calibration accuracy of similar to 1.3% in all bands. The median 5s point source depths in ugriz are 23.9, 24.8, 24.5, 24.2, and 23.5 mag. The SMASH data have already been used to discover the Hydra II Milky Way satellite, the SMASH 1 old globular cluster likely associated with the LMC, and extended stellar populations around the LMC out to R. similar to. 18.4 kpc. SMASH DR1 contains measurements of similar to 100 million objects distributed in 61 fields. A prototype version of the NOAO Data Lab provides data access and exploration tools.
KW  - galaxies: dwarf
KW  - galaxies: individual (Large Magellanic Cloud, Small Magellanic Cloud)
KW  - Local Group
KW  - Magellanic Clouds
KW  - surveys
Y1  - 2017
U6  - https://doi.org/10.3847/1538-3881/aa8d1c
SN  - 0004-6256
SN  - 1538-3881
VL  - 154
SP  - 310
EP  - 326
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Naze, Yael
A1  - Wang, Q. Daniel
A1  - Chu, You-Hua
A1  - Gruendl, Robert
A1  - Oskinova, Lida
T1  - A deep chandra observation of the giant HII region N11. I. x-ray sorces  in the field
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Supplement series
N2  - A very sensitive X-ray investigation of the giant HII region N11 in the Large Megallanic Cloud was performed using the Chandra X-ray Observatory. The 300 ks observation reveals X-ray sources with luminosities down to 10(32) erg s(-1), increasing the number of known point sources in the field by more than a factor of five. Among these detections are 13 massive stars (3 compact groups of massive stars, 9 O stars, and one early B star) with log(L-X/L-BOL) similar to -6.5 to -7, which may suggest that they are highly magnetic or colliding-wind systems. On the other hand, the stacked signal for regions corresponding to undetected O stars yields log(L-X/L-BOL) similar to -7.3, i.e., an emission level comparable to similar Galactic stars despite the lower metallicity. Other point sources coincide with 11 foreground stars, 6 late-B/A stars in N11, and many background objects. This observation also uncovers the extent and detailed spatial properties of the soft, diffuse emission regions, but the presence of some hotter plasma in their spectra suggests contamination by the unresolved stellar population.
KW  - galaxies: star clusters: general
KW  - ISM: individual objects (LMC N11)
KW  - Magellanic Clouds
KW  - X-rays: stars
Y1  - 2014
U6  - https://doi.org/10.1088/0067-0049/213/2/23
SN  - 0067-0049
SN  - 1538-4365
VL  - 213
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Martin, Nicolas F.
A1  - Nidever, David L.
A1  - Besla, Gurtina
A1  - Olsen, Knut
A1  - Walker, Alistair R.
A1  - Vivas, A. Katherina
A1  - Gruendl, Robert A.
A1  - Kaleida, Catherine C.
A1  - Munoz, Ricardo R.
A1  - Blum, Robert D.
A1  - Saha, Abhijit
A1  - Conn, Blair C.
A1  - Bell, Eric F.
A1  - Chu, You-Hua
A1  - Cioni, Maria-Rosa L.
A1  - de Boer, Thomas J. L.
A1  - Gallart, Carme
A1  - Jin, Shoko
A1  - Kunder, Andrea
A1  - Majewski, Steven R.
A1  - Martinez-Delgado, David
A1  - Monachesi, Antonela
A1  - Monelli, Matteo
A1  - Monteagudo, Lara
A1  - Noel, Noelia E. D.
A1  - Olszewski, Edward W.
A1  - Stringfellow, Guy S.
A1  - van der Marel, Roeland P.
A1  - Zaritsky, Dennis
T1  - Hydra II: A faint and compact milky way dwarf galaxy found in the survey of the magellanic stellar history
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters
N2  - We present the discovery of a new dwarf galaxy, Hydra II, found serendipitously within the data from the ongoing Survey of the Magellanic Stellar History conducted with the Dark Energy Camera on the Blanco 4 m Telescope. The new satellite is compact (r(h) = 68 +/- 11 pc) and faint (MV = -4.8 +/- 0.3), but well within the realm of dwarf galaxies. The stellar distribution of Hydra II in the color-magnitude diagram is well-described by a metal-poor ([Fe/H] = -2.2) and old (13 Gyr) isochrone and shows a distinct blue horizontal branch, some possible red clump stars, and faint stars that are suggestive of blue stragglers. At a heliocentric distance of 134 +/- 10 kpc, Hydra II is located in a region of the Galactic halo that models have suggested may host material from the leading arm of the Magellanic Stream. A comparison with N-body simulations hints that the new dwarf galaxy could be or could have been a satellite of the Magellanic Clouds.
KW  - galaxies: individual (Hydra II)
KW  - Local Group
KW  - Magellanic Clouds
Y1  - 2015
U6  - https://doi.org/10.1088/2041-8205/804/1/L5
SN  - 2041-8205
SN  - 2041-8213
VL  - 804
IS  - 1
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - GEN
A1  - Guerrero, Martín A.
A1  - Chu, You-Hua
A1  - Hamann, Wolf-Rainer
A1  - Oskinova, Lida
A1  - Schönberner, Detlef
A1  - Todt, Helge Tobias
A1  - Steffen, Matthias
A1  - Ruiz, Nieves
A1  - Gruendl, Robert A.
A1  - Blair, William P.
T1  - Ablation and wind mass-loading in the born-again planetary nebula A 30
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - We present XMM-Newton and Chandra observations of the born-again planetary nebula A 30. These X-ray observations reveal a bright unresolved source at the position of the central star whose X-ray luminosity exceeds by far the model expectations for photospheric emission and for shocks within the stellar wind. We suggest that a “born-again hot bubble” may be responsible for this X-ray emission. Diffuse X-ray emission associated with the petal-like features and one of the H-poor knots seen in the optical is also found. The weakened emission of carbon lines in the spectrum of the diffuse emission can be interpreted as the dilution of stellar wind by mass-loading or as the detection of material ejected during a very late thermal pulse.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 563 
KW  - planetary nebulae: individual (A 30)
KW  - X-rays: ISM
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412341
SN  - 1866-8372
IS  - 563
ER  -