| Title | Shedding Light on the Compton-thick Active Galactic Nucleus in the Ultraluminous Infrared Galaxy UGC 5101 with Broadband X-Ray Spectroscopy |
| Authors | Oda, Saeko Tanimoto, Atsushi Ueda, Yoshihiro Imanishi, Masatoshi Terashima, Yuichi Ricci, Claudio |
| Affiliation | Kyoto Univ, Dept Astron, Kyoto 6068502, Japan. Natl Astron Observ Japan, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan. Natl Inst Nat Sci, Natl Astron Observ Japan, Subaru Telescope, 650 North Aohoku Pl, Hilo, HI 96720 USA. Grad Univ Adv Studies SOKENDAI, Dept Astron Sci, Mitaka, Tokyo 1818588, Japan. Ehime Univ, Dept Phys, Bunkyo Cho, Matsuyama, Ehime 7908577, Japan. Pontificia Univ Catolica Chile, Inst Astrofis, Casilla 306, Santiago 22, Chile. Peking Univ, Kavli Inst Astron & Astrophys, Beijing 100871, Peoples R China. |
| Keywords | galaxies: active galaxies: individual (UGC 5101) X-rays: galaxies SUPERMASSIVE BLACK-HOLES SPITZER-SPACE-TELESCOPE SUZAKU OBSERVATIONS SEYFERT-GALAXIES STAR-FORMATION ENERGY-SOURCES OBSCURED AGN XMM-NEWTON MU-M UGC-5101 |
| Issue Date | 2017 |
| Publisher | ASTROPHYSICAL JOURNAL |
| Citation | ASTROPHYSICAL JOURNAL.2017,835(2). |
| Abstract | We report the broadband X-ray spectra of the ultraluminous infrared galaxy (ULIRG) UGC. 5101 in the 0.25-100 keV band observed with the Swift/Burst Alert Telescope (BAT), Nuclear Spectroscopic Telescope Array (NuSTAR), Suzaku, XMM-Newton, and Chandra. A Compton-thick active galactic nucleus (AGN) obscured with a hydrogen column density of approximate to 1.3 x 10(24) cm(-2) is detected above 10 keV. A spectral fit with a numerical torus model favors a large half-opening angle of the torus, >41 degrees, suggesting that the covering fraction of material heavily obscuring the X-ray source is moderate. The intrinsic 2-10 keV luminosity is determined to be approximate to 1.4 x 10(43) erg s(-1), which is approximate to 2.5 times larger than the previous estimate using only data below 10 keV with a simple spectral model. We find that UGC. 5101 shows the ratio between the [O IV] (26) mu m line and 2-10 keV luminosities similar to those of normal Seyfert galaxies, along with other ULIRGs observed with NuSTAR, indicating that a significant portion of local ULIRGs are not really "X-ray faint" with respect to the flux of forbidden lines originating from the narrow-line region. We propose a possible scenario that (1) the AGN in UGC 5101 is surrounded not only by Compton-thick matter located close to the equatorial plane but also by Compton-thin (N-H similar to 10(21) cm(-2)) matter in the torus-hole region and (2) it is accreting at a high Eddington rate with a steep UV to X-ray spectral energy distribution. Nevertheless, we argue that AGNs in many ULIRGs do not look extraordinary (i.e., extremely X-ray faint), as suggested by recent works, compared with normal Seyferts. |
| URI | http://hdl.handle.net/20.500.11897/475253 |
| ISSN | 0004-637X |
| DOI | 10.3847/1538-4357/835/2/179 |
| Indexed | SCI(E) |
| Appears in Collections: | 科维理天文与天体物理研究所 |
