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Title: Photoionization-driven Absorption-line Variability in Balmer Absorption Line Quasar LBQS 1206+1052

Abstract

In this paper we present an analysis of absorption-line variability in mini-BAL quasar LBQS 1206+1052. The Sloan Digital Sky Survey spectrum demonstrates that the absorption troughs can be divided into two components of blueshift velocities of ∼700 and ∼1400 km s{sup −1} relative to the quasar rest frame. The former component shows rare Balmer absorption, which is an indicator of high-density absorbing gas; thus, the quasar is worth follow-up spectroscopic observations. Our follow-up optical and near-infrared spectra using MMT, YFOSC, TSpec, and DBSP reveal that the strengths of the absorption lines vary for both components, while the velocities do not change. We reproduce all of the spectral data by assuming that only the ionization state of the absorbing gas is variable and that all other physical properties are invariable. The variation of ionization is consistent with the variation of optical continuum from the V -band light curve. Additionally, we cannot interpret the data by assuming that the variability is due to a movement of the absorbing gas. Therefore, our analysis strongly indicates that the absorption-line variability in LBQS 1206+1052 is photoionization driven. As shown from photoionization simulations, the absorbing gas with blueshift velocity of ∼700 km s{sup −1} has amore » density in the range of 10{sup 9} to 10{sup 10} cm{sup −3} and a distance of ∼1 pc, and the gas with blueshift velocity of ∼1400 km s{sup −1} has a density of 10{sup 3} cm{sup −3} and a distance of ∼1 kpc.« less

Authors:
; ; ; ; ; ; ;  [1]; ;  [2]; ;  [3];  [4]
  1. Polar Research Institute of China, 451 Jinqiao Road, Shanghai (China)
  2. Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan (China)
  3. Department of Astronomy, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui (China)
  4. Lehigh University, 27 Memorial Drive West, Bethlehem, PA 18015 (United States)
Publication Date:
OSTI Identifier:
22661222
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; 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; ABSORPTION; DENSITY; DIAGRAMS; EVOLUTION; GALAXIES; INFRARED SPECTRA; PHOTOIONIZATION; QUASARS; SIMULATION; VISIBLE RADIATION

Citation Formats

Sun, Luming, Zhou, Hongyan, Ji, Tuo, Jiang, Peng, Liu, Bo, Pan, Xiang, Shi, Xiheng, Zhang, Shaohua, Liu, Wenjuan, Wang, Jianguo, Wang, Tinggui, Yang, Chenwei, and Miller, Lauren P., E-mail: lmsun@mail.ustc.edu.cn. Photoionization-driven Absorption-line Variability in Balmer Absorption Line Quasar LBQS 1206+1052. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA63EB.
Sun, Luming, Zhou, Hongyan, Ji, Tuo, Jiang, Peng, Liu, Bo, Pan, Xiang, Shi, Xiheng, Zhang, Shaohua, Liu, Wenjuan, Wang, Jianguo, Wang, Tinggui, Yang, Chenwei, & Miller, Lauren P., E-mail: lmsun@mail.ustc.edu.cn. Photoionization-driven Absorption-line Variability in Balmer Absorption Line Quasar LBQS 1206+1052. United States. doi:10.3847/1538-4357/AA63EB.
Sun, Luming, Zhou, Hongyan, Ji, Tuo, Jiang, Peng, Liu, Bo, Pan, Xiang, Shi, Xiheng, Zhang, Shaohua, Liu, Wenjuan, Wang, Jianguo, Wang, Tinggui, Yang, Chenwei, and Miller, Lauren P., E-mail: lmsun@mail.ustc.edu.cn. Sat . "Photoionization-driven Absorption-line Variability in Balmer Absorption Line Quasar LBQS 1206+1052". United States. doi:10.3847/1538-4357/AA63EB.
@article{osti_22661222,
title = {Photoionization-driven Absorption-line Variability in Balmer Absorption Line Quasar LBQS 1206+1052},
author = {Sun, Luming and Zhou, Hongyan and Ji, Tuo and Jiang, Peng and Liu, Bo and Pan, Xiang and Shi, Xiheng and Zhang, Shaohua and Liu, Wenjuan and Wang, Jianguo and Wang, Tinggui and Yang, Chenwei and Miller, Lauren P., E-mail: lmsun@mail.ustc.edu.cn},
abstractNote = {In this paper we present an analysis of absorption-line variability in mini-BAL quasar LBQS 1206+1052. The Sloan Digital Sky Survey spectrum demonstrates that the absorption troughs can be divided into two components of blueshift velocities of ∼700 and ∼1400 km s{sup −1} relative to the quasar rest frame. The former component shows rare Balmer absorption, which is an indicator of high-density absorbing gas; thus, the quasar is worth follow-up spectroscopic observations. Our follow-up optical and near-infrared spectra using MMT, YFOSC, TSpec, and DBSP reveal that the strengths of the absorption lines vary for both components, while the velocities do not change. We reproduce all of the spectral data by assuming that only the ionization state of the absorbing gas is variable and that all other physical properties are invariable. The variation of ionization is consistent with the variation of optical continuum from the V -band light curve. Additionally, we cannot interpret the data by assuming that the variability is due to a movement of the absorbing gas. Therefore, our analysis strongly indicates that the absorption-line variability in LBQS 1206+1052 is photoionization driven. As shown from photoionization simulations, the absorbing gas with blueshift velocity of ∼700 km s{sup −1} has a density in the range of 10{sup 9} to 10{sup 10} cm{sup −3} and a distance of ∼1 pc, and the gas with blueshift velocity of ∼1400 km s{sup −1} has a density of 10{sup 3} cm{sup −3} and a distance of ∼1 kpc.},
doi = {10.3847/1538-4357/AA63EB},
journal = {Astrophysical Journal},
number = 2,
volume = 838,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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