Suzaku Observations of Local Ultraluminous Infrared Galaxies
Abstract
We report the results from our analysis of Suzaku XIS (0.5-10 keV) and HXD/PIN (15-40 keV) observations of five well-known local ultraluminous infrared galaxies (ULIRGs). The XIS observations of IRAS F05189-2524 and Mrk 273 reveal strong iron lines consistent with Fe Kalpha and changes in spectral shapes with respect to previous Chandra and XMM-Newton observations. Mrk 273 is also detected by the HXD/PIN at 1.8-sigma. For IRAS F05189-2524, modeling of the data from the different epochs suggests that the change in spectral shape is likely due to the central source switching off, leaving behind a residual reflection spectrum, or an increase in the absorbing column. An increase in the covering fraction of the absorber can describe the spectral variations seen in Mrk 273. The absorption-corrected 2-10 keV to infrared luminosity ratio is consistent with those found in PG Quasars. The 0.5-10 keV spectrum of PKS 1345+12 and Arp 220 seem unchanged from previous observations. An ionized iron line is prominent in the Arp 220 spectrum. IRAS F08572+3915 is undetected in both the XIS and HXD/PIN, but the analysis of unpublished Chandra data provides a new measurement at low energies. We acknowledge support from the NASA/Suzaku Guest Observer Program under grant NNX06AI39G.
- Publication:
-
American Astronomical Society Meeting Abstracts #213
- Pub Date:
- January 2009
- Bibcode:
- 2009AAS...21333203T