Exceptional AGN long-timescale X-ray variability: The case of PHL 1092

被引：2
作者：
Miniutti, G. [1 ]
Brandt, W. N. [2 ,3 ]
Schneider, D. P. [2 ,3 ]
Fabian, A. C. [4 ]
Gallo, L. C. [5 ]
Boller, Th.
机构：
[1] CSIC INTA, Ctr Astrobiol, ESA, Dept Astrofis, POB 78, Madrid 28691, Spain
[2] Penn State Univ, Dept Astron & Astrophys, Davey Lab, Univeristy Park, PA 16802 USA
[3] Penn State Univ, Inst Gravitat & Cosmos, University Pk, PA 16802 USA
[4] Inst Astron, Cambridge CB3 0HA, England
[5] St Marys Univ, Dept Astron Phys, Halifax, NS B3H 3C3, Canada
来源：
TIDAL DISRUPTION EVENTS AND AGN OUTBURSTS | 2012年 / 39卷
关键词：
ACTIVE GALACTIC NUCLEI; XMM-NEWTON; REFLECTION; QUASARS; LINE; EMISSION; SPECTRA; EXCESS;
D O I：
10.1051/epjconf/20123906002
中图分类号：
P1 [天文学];
学科分类号：
0704 ;
摘要：
PHL 1092 is a z similar to 0.4 high-luminosity counterpart of the class of Narrow-Line Seyfert 1 galaxies. In 2008, PHL 1092 was found to be in a remarkably low X-ray flux state during an XMM-Newton observation. Its 2 keV flux density had dropped by a factor of similar to 260 with respect to a previous observation performed 4.5 yr earlier. The UV flux remained almost constant, resulting in a significant steepening of the optical-to-X-ray slope alpha(ox) from -1.57 to -2.51, making PHL 1092 one of the most extreme X-ray weak quasars with no observed broad absorption lines (BALs) in the UV. We have monitored the source since 2008 with three further XMM-Newton observations, producing a simultaneous UV and X-ray database spanning almost 10 yr in total in the activity of the source. We present here results from our monitoring campaign.
引用
收藏
页数：4
相关论文
共 19 条
[1]   Intrinsic disc emission and the soft X-ray excess in active galactic nuclei [J].
Done, Chris ;
Davis, S. W. ;
Jin, C. ;
Blaes, O. ;
Ward, M. .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 420 (03) :1848-1860
[2]   Broad line emission from iron K- and L-shell transitions in the active galaxy 1H 0707-495 [J].
Fabian, A. C. ;
Zoghbi, A. ;
Ross, R. R. ;
Uttley, P. ;
Gallo, L. C. ;
Brandt, W. N. ;
Blustin, A. J. ;
Boller, T. ;
Caballero-Garcia, M. D. ;
Larsson, J. ;
Miller, J. M. ;
Miniutti, G. ;
Ponti, G. ;
Reis, R. C. ;
Reynolds, C. S. ;
Tanaka, Y. ;
Young, A. J. .
NATURE, 2009, 459 (7246) :540-542
[3]  
Fabian A. C., 2012, ARXIV12085898
[4]   X-ray reflection in the narrow-line Seyfert 1 galaxy 1H 0707-495 [J].
Fabian, AC ;
Miniutti, G ;
Gallo, L ;
Boller, T ;
Tanaka, Y ;
Vaughan, S ;
Ross, RR .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2004, 353 (04) :1071-1077
[5]   Are optically selected quasars universally X-ray luminous? X-ray-UV relations in Sloan Digital Sky Survey quasars [J].
Gibson, Robert R. ;
Brandt, W. N. ;
Schneider, Donald P. .
ASTROPHYSICAL JOURNAL, 2008, 685 (02) :773-786
[6]   Is the soft excess in active galactic nuclei real? [J].
Gierlinski, M ;
Done, C .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2004, 349 (01) :L7-L11
[7]   A combined optical and X-ray study of unobscured type 1 active galactic nuclei - I. Optical spectra and spectral energy distribution modelling [J].
Jin, Chichuan ;
Ward, Martin ;
Done, Chris ;
Gelbord, Jonathan .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 420 (03) :1825-1847
[8]   The X-ray properties of the most luminous quasars from the sloan digital sky survey [J].
Just, D. W. ;
Brandt, W. N. ;
Shemmer, O. ;
Steffen, A. T. ;
Schneider, D. P. ;
Chartas, G. ;
Garmire, G. P. .
ASTROPHYSICAL JOURNAL, 2007, 665 (02) :1004-1022
[9]   The intrinsically X-ray-weak quasar PHL 1811. II. Optical and UV spectra and analysis [J].
Leighly, Karen M. ;
Halpern, Jules P. ;
Jenkins, Edward B. ;
Casebeer, Darrin .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2007, 173 (01) :1-36
[10]   The intrinsically X-ray weak quasar PHL 1811. I. X-ray observations and spectral energy distribution [J].
Leighly, Karen M. ;
Halpern, Jules P. ;
Jenkins, Edward B. ;
Grupe, Dirk ;
Choi, Jiehae ;
Prescott, Kimberly B. .
ASTROPHYSICAL JOURNAL, 2007, 663 (01) :103-117
12