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XMM-Newton View of the Ultraluminous X-Ray Sources in M51
Dewangan, Gulab C.; Griffiths, Richard E.; Miyaji, Takamitsu +2 more
We present results based on XMM-Newton observations of the nearby spiral galaxy M51 (NGC 5194 and NGC 5195). We confirm the presence of the seven known ultraluminous X-ray sources (ULXs) with luminosities exceeding the Eddington luminosity for a 10 Msolar black hole, a low-luminosity active galactic nucleus (LLAGN) with 2-10 keV luminos…
A New Technique for Deriving Prominence Mass from SOHO/EIT Fe XII (19.5 Nanometers) Absorption Features
Gilbert, Holly R.; Holzer, Thomas E.; MacQueen, R. M.
It is presently unclear what role prominences play in the initiation and dynamics of coronal mass ejections (CMEs), although erupting prominences are strongly correlated with CMEs. The masses of prominences involved in CMEs are not generally measured, but the accurate determination of such masses may help in assessing the dynamical importance of p…
Evolution in the Cluster Early-Type Galaxy Size-Surface Brightness Relation at z~=1
Demarco, R.; Infante, L.; Zheng, W. +41 more
We investigate the evolution in the distribution of surface brightness, as a function of size, for elliptical and S0 galaxies in the two clusters RDCS J1252.9-2927 (z=1.237) and RX J0152.7-1357 (z=0.837). We use multicolor imaging with the Advanced Camera for Surveys on the Hubble Space Telescope to determine these sizes and surface brightnesses. …
X-Ray Spectroscopy of Candidate Ultracompact X-Ray Binaries
Chakrabarty, Deepto; Juett, Adrienne M.
We present high-resolution spectroscopy of the neutron star/low-mass X-ray binaries (LMXBs) 4U 1850-087 and 4U 0513-40 as part of our continuing study of known and candidate ultracompact binaries. The LMXB 4U 1850-087 is one of four systems in which we had previously inferred an unusual Ne/O ratio in the absorption along the line of sight, most li…
SDSS J140228.22+632133.3: A New Spectroscopically Selected Gravitational Lens
Treu, Tommaso; Koopmans, Léon V. E.; Bolton, Adam S. +2 more
We present Gemini integral-field unit spectroscopy and Hubble Space Telescope (HST) F435W- and F814W-band images of a newly discovered four-image gravitational lens, SDSS J140228.22+632133.3 (hereafter SDSSJ1402). The system is the first of 49 spectroscopically selected gravitational lens candidates to be imaged with the Advanced Camera for Survey…
The Acoustic Showerglass. II. Imaging Active Region Subphotospheres
Braun, D. C.; Lindsey, Charles
Seismic diagnostics of the shallow subphotospheres of strong active regions are substantially impacted by large amplitude and phase perturbations introduced by overlying surface magnetic fields. These function as an ``acoustic showerglass'' that impairs the coherence of acoustic waves impinging onto the solar surface from below, degrading images o…
The X-Ray Properties of M101 ULX-1 = CXOKM101 J140332.74+542102
Mukai, K.; Kuntz, K. D.; Corbet, R. H. D. +2 more
We report our analysis of X-ray data on M101 ULX-1, concentrating on high-state Chandra and XMM-Newton observations. We find that the high state of M101 ULX-1 may have a preferred recurrence timescale. If so, the underlying clock may have periods around 160 or 190 days, or possibly around 45 days. Its short-term variations resemble those of X-ray …
Type 2 Counterparts of Narrow-Line Seyfert 1 Galaxies
Dewangan, G. C.; Griffiths, R. E.
Unified models based on viewing angle successfully explain the observed differences between type 1 and type 2 Seyfert galaxies. The existence of a range in accretion rates (m˙~0.001-1) relative to the Eddington rate (from broad-line Seyfert 1's to narrow-line Seyfert 1's, or NLS1's) and the unification of Seyfert galaxies imply that there must be …
Fluorescent Molecular Hydrogen Emission in IC 63: FUSE, Hopkins Ultraviolet Telescope, and Rocket Observations
France, K.; Feldman, P. D.; Andersson, B. -G. +1 more
We present far-ultraviolet observations of IC 63, an emission/reflection nebula illuminated by the B0.5 IV star γ Cas, located 1.3 pc from the nebula. Molecular hydrogen fluorescence was detected first in IC 63 by IUE and later at shorter wavelengths by ORFEUS. Here we present Far Ultraviolet Spectroscopic Explorer (FUSE) observations toward three…
Cl 1205+44: A Fossil Group at z = 0.59
Romer, A. K.; Adami, C.; Durret, F. +6 more
This is a report of Chandra, XMM-Newton, Hubble Space Telescope, and Astrophysical Research Consortium telescope observations of an extended X-ray source at z=0.59. The apparent member galaxies range from spiral to elliptical, and are all relatively red (i'-Ks about 3). We interpret this object to be a fossil group based on t…