Search Publications
Multi-wavelength Studies of Spectacular Ram Pressure Stripping of a Galaxy: Discovery of an X-Ray Absorption Feature
Makishima, Kazuo; Nakazawa, Kazuhiro; Gu, Liyi +5 more
We report the detection of an X-ray absorption feature near the galaxy M86 in the Virgo cluster. The absorber has a column density of 2-3 × 1020 cm-2, and its position coincides with the peak of an intracluster H I cloud which was removed from the galaxy NGC 4388 presumably by ram pressure. These results indicate that the H I…
The Local Environment of Ultraluminous X-Ray Sources Viewed by XMM-Newton's Optical Monitor
Berghea, C. T.; Dudik, R. P.; Winter, L. M. +1 more
We have used XMM-Newton's Optical Monitor (OM) images to study the local environment of a sample of 27 ultraluminous X-ray sources (ULXs) in nearby galaxies. UVW1 fluxes were extracted from 100 pc regions centered on the ULX positions. We find that at least 4 ULXs (out of 10 published) have spectral types that are consistent with previous literatu…
SMM J04135+10277: A Candidate Early-stage "Wet-Dry" Merger of Two Massive Galaxies at z = 2.8
Riechers, Dominik A.
We report interferometric imaging of CO(J = 3→2) emission toward the z = 2.846 submillimeter-selected galaxy SMM J04135+10277, using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). SMM J04135+10277 was previously thought to be a gas-rich, submillimeter-selected quasar, with the highest molecular gas mass among high-z quasars …
Gemini Spectroscopy of Ultracompact Dwarfs in the Fossil Group NGC 1132
Madrid, Juan P.; Donzelli, Carlos J.
A spectroscopic follow-up of ultracompact dwarf (UCD) candidates in the fossil group NGC 1132 is undertaken with the Gemini Multi Object Spectrograph. These new Gemini spectra prove the presence of six UCDs in the fossil group NGC 1132 at a distance of D ~ 100 Mpc and a recessional velocity of vr = 6935 ± 11 km s-1. The brigh…
Rapid Spectral Changes of Cygnus X-1 in the Low/Hard State with Suzaku
Yamada, S.; Noda, H.; Negoro, H. +3 more
Rapid spectral changes in the hard X-ray on a timescale down to ~0.1 s are studied by applying a "shot analysis" technique to the Suzaku observations of the black hole binary Cygnus X-1, performed on 2008 April 18 during the low/hard state. We successfully obtained the shot profiles, covering 10-200 keV with the Suzaku HXD-PIN and HXD-GSO detector…
Multiwavelength Observations of the Black Hole Transient XTE J1752-223 during Its 2010 Outburst Decay
Tomsick, J. A.; Corbel, S.; Kalemci, E. +6 more
Galactic black hole transients show many interesting phenomena during outburst decays. We present simultaneous X-ray (RXTE, Swift, and INTEGRAL), and optical/near-infrared (O/NIR) observations (SMARTS) of the X-ray transient XTE J1752-223 during its outburst decay in 2010. The multiwavelength observations over 150 days in 2010 cover the transition…
Characteristic Length of Energy-containing Structures at the Base of a Coronal Hole
Goode, P. R.; Zank, G. P.; Abramenko, V. I. +4 more
An essential parameter for models of coronal heating and fast solar wind acceleration that rely on the dissipation of MHD turbulence is the characteristic energy-containing length λ of the squared velocity and magnetic field fluctuations (u 2 and b 2) transverse to the mean magnetic field inside a coronal hole (CH)…
Spectral Energy Distributions of Low-luminosity Radio Galaxies at z ~1-3: A High-z View of the Host/AGN Connection
Sparks, William B.; Chiaberge, Marco; Capetti, Alessandro +3 more
We study the spectral energy distributions, SEDs (from FUV to MIR bands), of the first sizeable sample of 34 low-luminosity radio galaxies at high redshifts, selected in the COSMOS field. To model the SEDs, we use two different template-fitting techniques: (1) the Hyperz code that only considers single stellar templates and (2) our own developed t…
PSR J1840-1419: A Very Cool Neutron Star
Kramer, M.; McLaughlin, M. A.; Bassa, C. G. +4 more
We present upper limits on the X-ray emission for three neutron stars. For PSR J1840-1419, with a characteristic age of 16.5 Myr, we calculate a blackbody temperature upper limit (at 99% confidence) of kT ∞ bb < 24+17 -10 eV, making this one of the coolest neutron stars known. PSRs J1814-1744 and J184…
A Generalized Power-law Diagnostic for Infrared Galaxies at z > 1: Active Galactic Nuclei and Hot Interstellar Dust
Caputi, K. I.
I present a generalized power-law (PL) diagnostic which allows one to identify the presence of active galactic nuclei (AGNs) in infrared (IR) galaxies at z > 1, down to flux densities at which the extragalactic IR background is mostly resolved. I derive this diagnostic from the analysis of 174 galaxies with S ν(24 µm)>80 &mi…