Search Publications
Star Formation in LINER Host Galaxies at z ~ 0.3
Berta, Stefano; Pozzi, Francesca; Lutz, Dieter +8 more
We present the results of a Herschel-PACS study of a sample of 97 low-ionization nuclear emission-line regions (LINERs) at redshift z ~ 0.3 selected from the zCOSMOS survey. Of these sources, 34 are detected in at least one PACS band, enabling reliable estimates of the far-infrared L FIR luminosities, and a comparison to the FIR luminos…
Testing Gravitational Lensing as the Source of Enhanced Strong Mg II Absorption toward Gamma-Ray Bursts
Schmidt, Brian P.; Onken, Christopher A.; Tucker, Brad E. +3 more
Sixty percent of gamma-ray bursts (GRBs) reveal strong Mg II absorbing systems, which is a factor of ~2 times the rate seen along lines of sight to quasars. Previous studies argue that the discrepancy in the strong Mg II covering factor is most likely to be the result of either quasars being obscured due to dust or the consequence of many GRBs bei…
Far-infrared Imaging Observations of the Chamaeleon Region
Takita, Satoshi; Kaneda, Hidehiro; Kawamura, Akiko +4 more
We have carried out far-infrared imaging observations toward the Chamaeleon star-forming region by the Far-Infrared Surveyor (FIS) on board the AKARI satellite. The AKARI images cover a total area of 33.79 deg2, corresponding to 210 pc2 at the distance to the source. Using the FIS bands of 65-160 µm and the COBE/DIRBE b…
XMM-Newton Observations of Two Candidate Supernova Remnants
Pavlov, G. G.; Kargaltsev, O.; Misanovic, Z. +1 more
Candidate supernova remnants (SNRs) G23.5+0.1 and G25.5+0.0 were observed by XMM-Newton in the course of a snapshot survey of plerionic and composite SNRs in the Galactic plane. In the field of G23.5+0.1, we detected an extended source, ~3' in diameter, which we tentatively interpret as a pulsar wind nebula (PWN) of the middle-aged radio pulsar B1…
A Multi-spacecraft View of a Giant Filament Eruption during 2009 September 26/27
Gosain, Sanjay; Schmieder, Brigitte; Artzner, Guy +2 more
We analyze multi-spacecraft observations of a giant filament eruption that occurred during 2009 September 26 and 27. The filament eruption was associated with a relatively slow coronal mass ejection. The filament consisted of a large and a small part, and both parts erupted nearly simultaneously. Here we focus on the eruption associated with the l…
An Angle-dependent Synchrotron Self-Compton Model for Relativistic Jet Sources
Böttcher, M.; Jamil, O.
We report on the development of a numerical code to calculate the angle-dependent synchrotron + synchrotron self-Compton radiation from relativistic jet sources with partially ordered magnetic fields and anisotropic particle distributions. Using a multi-zone radiation transfer approach, we can simulate magnetic-field configurations ranging from pe…
AMUSE-Virgo. III. Mid-infrared Photometry of Early-type Galaxies and Limits on Obscured Nuclear Emission
Treu, Tommaso; Antonucci, Robert; Gallo, Elena +3 more
We complete our census of low-level nuclear activity in Virgo Cluster early-type galaxies by searching for obscured emission using Spitzer Space Telescope mid-infrared (MIR) imaging at 24 µm. Of a total sample of 95 early-type galaxies, 53 objects are detected, including 16 showing kiloparsec-scale dust in optical images. One-dimensional and…
A Second Neutron Star in M4?
Thompson, Ian B.; Kaluzny, J.; Rozanska, A. +2 more
We show that the optical counterpart of the X-ray source CX 1 in M4 is a ~20th magnitude star, located in the color-magnitude diagram on (or very close to) the main sequence of the cluster, and exhibiting sinusoidal variations of the flux. We find the X-ray flux to be also periodically variable, with X-ray and optical minima coinciding. Stability …
On the X-Ray Emission Mechanisms of the Persistent Source and Very Low Fluence Bursts of SGR J0501+4516
Kouveliotou, Chryssa; Göǧüş, Ersin; Lin, Lin +1 more
We present here a detailed spectral study of the X-ray emission of the persistent source and the low-fluence bursts of SGR J0501+4516 observed during a deep XMM-Newton observation near the peak of its 2008 outburst. For the persistent emission, we employ a physically motivated continuum emission model and spectroscopically determine important sour…
Giant H II Regions in M101. I. X-Ray Analysis of Hot Gas
Feng, Li; Chu, You-Hua; Wang, Q. Daniel +4 more
We performed a Chandra X-ray study of three giant H II regions (GHRs), NGC 5461, NGC 5462, and NGC 5471, in the spiral galaxy M101. The X-ray spectra of the three GHRs all contain a prominent thermal component with a temperature of ~0.2 keV. In NGC 5461, the spatial distribution of the soft (<1.5 keV) X-ray emission is generally in agreement wi…