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SDSS J160531.84+174826.1: A Dwarf Disk Galaxy With An Intermediate-Mass Black Hole

Xiaobo Dong·Tinggui Wang·Weimin Yuan·Hongguang Shan·Hongyan Zhou·Lulu Fan·Liming Dou·Huiyuan Wang·Junxian Wang·Honglin Lu
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Abstract

We report the discovery of a dwarf Seyfert 1 active galactic nucleus (AGN) with a candidate intermediate-mass black hole hosted by the dwarf galaxy SDSS J160531.84+174826.1 at z=0.032. A broad component of the H-alpha line with FWHM=781 km/s is detected in its optical spectrum, and a bright, point-like nucleus is evident from a HST imaging observation. Non-thermal X-ray emission is also detected from the nucleus. The black hole mass, as estimated from the luminosity and width of the broad H-alpha component, is about 7x10^4 \msun. The host galaxy appears to be a disk galaxy with a boxy bulge or nuclear bar; with an absolute magnitude of M_R = -17.8 (M_B = -16.4), it is among the least luminous host galaxies ever identified for a Seyfert 1.

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Xiaobo Dong, Tinggui Wang, Weimin Yuan, Hongguang Shan, Hongyan Zhou, Lulu Fan, Liming Dou, Huiyuan Wang, Junxian Wang, Honglin Lu. 2006-12-16. SDSS J160531.84+174826.1: A Dwarf Disk Galaxy With An Intermediate-Mass Black Hole. https://doi.org/10.1086/510899

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