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A Multiphase Absorber Containing O VI and Broad H I Directly Tracing 106 K Plasma at Low Redshift Toward HE 0153-4520
Savage, B. D.; Narayanan, A.; Wakker, B. P. +1 more
Observations of the QSO HE 0153-4520 (z em = 0.450) with the Cosmic Origins Spectrograph (COS) from 1134 to 1796 Å with a resolution of ~17 km s-1 and a signal-to-noise ratio per resolution element of 20-40 are used to study a multiphase partial Lyman limit system (LLS) at z = 0.22601 tracing both cool and hot gas. Far-Ultrav…
Molecular Gas in Lensed z >2 Quasar Host Galaxies and the Star Formation Law for Galaxies with Luminous Active Galactic Nuclei
Riechers, Dominik A.
We report the detection of luminous CO(J = 2→1), CO(J = 3→2), and CO(J = 4→3) emission in the strongly lensed high-redshift quasars B1938+666 (z = 2.059), HE 0230-2130 (z = 2.166), HE 1104-1805 (z = 2.322), and B1359+154 (z = 3.240), using the Combined Array for Research in Millimeter-wave Astronomy. B1938+666 was identified in a "blind" CO redshi…
Star Formation from DLA Gas in the Outskirts of Lyman Break Galaxies at z ~ 3
Rafelski, Marc; Chen, Hsiao-Wen; Wolfe, Arthur M.
We present evidence for spatially extended low surface brightness emission around Lyman break galaxies (LBGs) in the V-band image of the Hubble Ultra Deep Field, corresponding to the z ~ 3 rest-frame far-UV (FUV) light, which is a sensitive measure of star formation rates (SFRs). We find that the covering fraction of molecular gas at z ~ 3 is not …
Discovery of an Ultrasoft X-Ray Transient Source in the 2XMM Catalog: A Tidal Disruption Event Candidate
Lin, Dacheng; Grupe, Dirk; Carrasco, Eleazar R. +3 more
We have discovered an ultrasoft X-ray transient source, 2XMMi J184725.1-631724, which was detected serendipitously in two XMM-Newton observations in the direction of the center of the galaxy IC 4765-f01-1504 at a redshift of 0.0353. These two observations were separated by 211 days, with the 0.2-10 keV absorbed flux increasing by a factor of about…
Spectroscopy of Luminous z > 7 Galaxy Candidates and Sources of Contamination in z > 7 Galaxy Searches
Kneib, J. -P.; Aussel, H.; Sanders, D. B. +22 more
We present three bright z +-dropout candidates selected from deep near-infrared (NIR) imaging of the COSMOS 2 deg2 field. All three objects match the 0.8-8 µm colors of other published z > 7 candidates but are 3 mag brighter, facilitating further study. Deep spectroscopy of two of the candidates covering 0.64-1.02 &m…
X-Ray and Optical Observations of the Unique Binary System HD 49798/RX J0648.0-4418
Tiengo, A.; Mereghetti, S.; Stella, L. +5 more
We report the results of XMM-Newton observations of HD 49798/RX J0648.0-4418, the only known X-ray binary consisting of a hot sub-dwarf and a white dwarf. The white dwarf rotates very rapidly (P = 13.2 s) and has a dynamically measured mass of 1.28 ± 0.05 M sun. Its X-ray emission consists of a strongly pulsed, soft component, well fit …
2011 February 15: Sunquakes Produced by Flux Rope Eruption
Green, L. M.; Zharkova, V. V.; Matthews, S. A. +1 more
We present an analysis of the 2011 February 15 X-class solar flare, previously reported to produce the first sunquake in solar cycle 24. Using acoustic holography, we confirm the first, and report a second, weaker, seismic source associated with this flare. We find that the two sources are located at either end of a sigmoid, which indicates the pr…
A 205 µm [N II] Map of the Carina Nebula
Stark, A. A.; Stacey, G. J.; Kamenetzky, J. +5 more
We present the results of a ~250 arcmin2 mapping of the 205 µm [N II] fine-structure emission over the northern Carina Nebula, including the Car I and Car II H II regions. Spectra were obtained using the South Pole Imaging Fabry-Perot Interferometer (SPIFI) at the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) a…
A Correlation Between Host Star Activity and Planet Mass for Close-in Extrasolar Planets?
Schmitt, J. H. M. M.; Poppenhaeger, K.
The activity levels of stars are influenced by several stellar properties, such as stellar rotation, spectral type, and the presence of stellar companions. Analogous to binaries, planetary companions are also thought to be able to cause higher activity levels in their host stars, although at lower levels. Especially in X-rays, such influences are …
The Circumstellar Environment of R Coronae Borealis: White Dwarf Merger or Final-helium-shell Flash?
Ivison, R. J.; Olofsson, G.; Bond, Howard E. +21 more
In 2007, R Coronae Borealis (R CrB) went into a historically deep and long decline. In this state, the dust acts like a natural coronagraph at visible wavelengths, allowing faint nebulosity around the star to be seen. Imaging has been obtained from 0.5 to 500 µm with Gemini/GMOS, Hubble Space Telescope/WFPC2, Spitzer/MIPS, and Herschel/SPIRE…