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Title: PHL 6625: A Minor Merger-associated QSO Behind NGC 247

Abstract

PHL 6625 is a luminous quasi-stellar object (QSO) at z = 0.3954 located behind the nearby galaxy NGC 247 ( z = 0.0005). Hubble Space Telescope observations revealed an arc structure associated with it. We report on spectroscopic observations with the Very Large Telescope and multiwavelength observations from the radio to the X-ray band for the system, suggesting that PHL 6625 and the arc are a close pair of merging galaxies, instead of a strong gravitational lens system. The QSO host galaxy is estimated to be (4–28) × 10{sup 10} M {sub ☉} and the mass of the companion galaxy is estimated to be M {sub *} = (6.8 ± 2.4) × 10{sup 9} M {sub ☉}, suggesting that this is a minor merger system. The QSO displays typical broad emission lines, from which a black hole mass of about (2–5) × 10{sup 8} M {sub ☉} and an Eddington ratio of about 0.01–0.05 can be inferred. The system represents an interesting and rare case where a QSO is associated with an ongoing minor merger, analogous to Arp 142.

Authors:
;  [1]; ;  [2];  [3];  [4];  [5];  [6]
  1. Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)
  2. Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)
  3. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100087 (China)
  4. National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012 (China)
  5. Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States)
  6. Center for Astrophysics, Tsinghua University, Beijing 100084 (China)
Publication Date:
OSTI Identifier:
22663551
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 841; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; EMISSION; GALAXIES; GALAXY NUCLEI; GRAVITATIONAL LENSES; INTERACTIONS; MASS; QUASARS; SPACE; TELESCOPES; X RADIATION

Citation Formats

Tao, Lian, Feng, Hua, Shen, Yue, Liu, Xin, Ho, Luis C., Ge, Junqiang, Kaaret, Philip, and Mao, Shude. PHL 6625: A Minor Merger-associated QSO Behind NGC 247. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA72F3.
Tao, Lian, Feng, Hua, Shen, Yue, Liu, Xin, Ho, Luis C., Ge, Junqiang, Kaaret, Philip, & Mao, Shude. PHL 6625: A Minor Merger-associated QSO Behind NGC 247. United States. doi:10.3847/1538-4357/AA72F3.
Tao, Lian, Feng, Hua, Shen, Yue, Liu, Xin, Ho, Luis C., Ge, Junqiang, Kaaret, Philip, and Mao, Shude. Thu . "PHL 6625: A Minor Merger-associated QSO Behind NGC 247". United States. doi:10.3847/1538-4357/AA72F3.
@article{osti_22663551,
title = {PHL 6625: A Minor Merger-associated QSO Behind NGC 247},
author = {Tao, Lian and Feng, Hua and Shen, Yue and Liu, Xin and Ho, Luis C. and Ge, Junqiang and Kaaret, Philip and Mao, Shude},
abstractNote = {PHL 6625 is a luminous quasi-stellar object (QSO) at z = 0.3954 located behind the nearby galaxy NGC 247 ( z = 0.0005). Hubble Space Telescope observations revealed an arc structure associated with it. We report on spectroscopic observations with the Very Large Telescope and multiwavelength observations from the radio to the X-ray band for the system, suggesting that PHL 6625 and the arc are a close pair of merging galaxies, instead of a strong gravitational lens system. The QSO host galaxy is estimated to be (4–28) × 10{sup 10} M {sub ☉} and the mass of the companion galaxy is estimated to be M {sub *} = (6.8 ± 2.4) × 10{sup 9} M {sub ☉}, suggesting that this is a minor merger system. The QSO displays typical broad emission lines, from which a black hole mass of about (2–5) × 10{sup 8} M {sub ☉} and an Eddington ratio of about 0.01–0.05 can be inferred. The system represents an interesting and rare case where a QSO is associated with an ongoing minor merger, analogous to Arp 142.},
doi = {10.3847/1538-4357/AA72F3},
journal = {Astrophysical Journal},
number = 2,
volume = 841,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
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