X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations

Sameer; W. N. Brandt; S. Anderson; P. B. Hall; M. Vivek; N. Filiz Ak; C. J. Grier; N. S. Ahmed; B. Luo; A. D. Myers; P. Rodríguez Hidalgo; J. Ruan; D. P. Schneider

doi:10.1093/mnras/sty2718

X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations

Sameer
, W. N. Brandt
, S. Anderson
, P. B. Hall
, M. Vivek
, N. Filiz Ak
, C. J. Grier
, N. S. Ahmed
, B. Luo
, A. D. Myers
, P. Rodríguez Hidalgo
, J. Ruan
, D. P. Schneider

Research output: Contribution to journal › Article › peer-review

11 Scopus citations

Abstract

We report on an X-ray and optical/ultraviolet (UV) study of eight broad absorption line (BAL) to non-BAL transforming quasars at z ≈ 1.7-2.2 over 0.29-4.95 rest-frame years with at least three spectroscopic epochs for each quasar from the SDSS, BOSS, Gemini, and ARC 3.5m telescopes. New Chandra observations obtained for these objects show that their values of α_ox and Δα_ox, as well as their spectral energy distributions, are consistent with those of non- BAL quasars. Moreover, our targets have X-ray spectral shapes that are, on average, consistent with weakened absorption with an effective power-law photon index of Γ_eff = 1.69_-0.25^+0.25. The newer Gemini and ARC 3.5m spectra reveal that the BAL troughs have remained absent since the BOSS observations where the BAL disappearance was discovered. The X-ray and optical/UV results in tandem are consistent with at least the X-ray-absorbing material moving out of the line of sight, leaving an X-ray-unabsorbed non-BAL quasar. The UV absorber might have become more highly ionized (in a shielding-gas scenario) or also moved out of the line of sight (in a wind-clumping scenario).

Original language	English (US)
Pages (from-to)	1121-1134
Number of pages	14
Journal	Monthly Notices of the Royal Astronomical Society
Volume	482
Issue number	1
DOIs	https://doi.org/10.1093/mnras/sty2718
State	Published - Jan 1 2019
Externally published	Yes

Keywords

Galaxies: active
Quasars: absorption lines
Quasars: general

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

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10.1093/mnras/sty2718

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Sameer, Brandt, W. N., Anderson, S., Hall, P. B., Vivek, M., Filiz Ak, N., Grier, C. J., Ahmed, N. S., Luo, B., Myers, A. D., Hidalgo, P. R., Ruan, J., & Schneider, D. P. (2019). X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations. Monthly Notices of the Royal Astronomical Society, 482(1), 1121-1134. https://doi.org/10.1093/mnras/sty2718

@article{4908371c885741628d9d51b34b4c92e6,

title = "X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations",

abstract = "We report on an X-ray and optical/ultraviolet (UV) study of eight broad absorption line (BAL) to non-BAL transforming quasars at z ≈ 1.7-2.2 over 0.29-4.95 rest-frame years with at least three spectroscopic epochs for each quasar from the SDSS, BOSS, Gemini, and ARC 3.5m telescopes. New Chandra observations obtained for these objects show that their values of αox and Δαox, as well as their spectral energy distributions, are consistent with those of non- BAL quasars. Moreover, our targets have X-ray spectral shapes that are, on average, consistent with weakened absorption with an effective power-law photon index of Γeff = 1.69-0.25+0.25. The newer Gemini and ARC 3.5m spectra reveal that the BAL troughs have remained absent since the BOSS observations where the BAL disappearance was discovered. The X-ray and optical/UV results in tandem are consistent with at least the X-ray-absorbing material moving out of the line of sight, leaving an X-ray-unabsorbed non-BAL quasar. The UV absorber might have become more highly ionized (in a shielding-gas scenario) or also moved out of the line of sight (in a wind-clumping scenario).",

keywords = "Galaxies: active, Quasars: absorption lines, Quasars: general",

author = "Sameer and Brandt, \{W. N.\} and S. Anderson and Hall, \{P. B.\} and M. Vivek and \{Filiz Ak\}, N. and Grier, \{C. J.\} and Ahmed, \{N. S.\} and B. Luo and Myers, \{A. D.\} and Hidalgo, \{P. Rodr{\'i}guez\} and J. Ruan and Schneider, \{D. P.\}",

note = "Funding Information: We thank the anonymous referee for his/her suggestions which helped improve the manuscript. We acknowledge helpful discussions with Chien-Ting Chen, Eric Feigelson, Sean McGraw, Qin-gling Ni, Yue Shen, Fabio Vito, Guang Yang, Weimin Yi, Ning-Xiao Zhang, and Shifu Zhu. S and WNB acknowledges support from NSF grant AST-1516784 and Chandra X-ray Center grant GO5-16089X. NFA acknowledges support from TUBITAK 115F037. BL acknowledges financial support from the National Key R\&D Program of China grant 2016YFA0400702 and National Natural Science Foundation of China grant 11673010. Funding Information: The expected value of αox for a typical radio-quiet quasar is calculated from the established αox–L2500{\AA} correlation given as equation (3) of J07. 2Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog{\'i}a e Innovaci{\'o}n Productiva (Argentina), and Minist{\'e}rio da Ci{\^e}ncia, Tecnologia e Inovac¸{\~a}o (Brazil). 3Based on observations obtained with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium. Publisher Copyright: {\textcopyright} 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.",

year = "2019",

month = jan,

day = "1",

doi = "10.1093/mnras/sty2718",

language = "English (US)",

volume = "482",

pages = "1121--1134",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "Oxford University Press",

number = "1",

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TY - JOUR

T1 - X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations

AU - Sameer,

AU - Brandt, W. N.

AU - Anderson, S.

AU - Hall, P. B.

AU - Vivek, M.

AU - Filiz Ak, N.

AU - Grier, C. J.

AU - Ahmed, N. S.

AU - Luo, B.

AU - Myers, A. D.

AU - Hidalgo, P. Rodríguez

AU - Ruan, J.

AU - Schneider, D. P.

N1 - Funding Information: We thank the anonymous referee for his/her suggestions which helped improve the manuscript. We acknowledge helpful discussions with Chien-Ting Chen, Eric Feigelson, Sean McGraw, Qin-gling Ni, Yue Shen, Fabio Vito, Guang Yang, Weimin Yi, Ning-Xiao Zhang, and Shifu Zhu. S and WNB acknowledges support from NSF grant AST-1516784 and Chandra X-ray Center grant GO5-16089X. NFA acknowledges support from TUBITAK 115F037. BL acknowledges financial support from the National Key R&D Program of China grant 2016YFA0400702 and National Natural Science Foundation of China grant 11673010. Funding Information: The expected value of αox for a typical radio-quiet quasar is calculated from the established αox–L2500Å correlation given as equation (3) of J07. 2Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovac¸ão (Brazil). 3Based on observations obtained with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium. Publisher Copyright: © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.

PY - 2019/1/1

Y1 - 2019/1/1

N2 - We report on an X-ray and optical/ultraviolet (UV) study of eight broad absorption line (BAL) to non-BAL transforming quasars at z ≈ 1.7-2.2 over 0.29-4.95 rest-frame years with at least three spectroscopic epochs for each quasar from the SDSS, BOSS, Gemini, and ARC 3.5m telescopes. New Chandra observations obtained for these objects show that their values of αox and Δαox, as well as their spectral energy distributions, are consistent with those of non- BAL quasars. Moreover, our targets have X-ray spectral shapes that are, on average, consistent with weakened absorption with an effective power-law photon index of Γeff = 1.69-0.25+0.25. The newer Gemini and ARC 3.5m spectra reveal that the BAL troughs have remained absent since the BOSS observations where the BAL disappearance was discovered. The X-ray and optical/UV results in tandem are consistent with at least the X-ray-absorbing material moving out of the line of sight, leaving an X-ray-unabsorbed non-BAL quasar. The UV absorber might have become more highly ionized (in a shielding-gas scenario) or also moved out of the line of sight (in a wind-clumping scenario).

AB - We report on an X-ray and optical/ultraviolet (UV) study of eight broad absorption line (BAL) to non-BAL transforming quasars at z ≈ 1.7-2.2 over 0.29-4.95 rest-frame years with at least three spectroscopic epochs for each quasar from the SDSS, BOSS, Gemini, and ARC 3.5m telescopes. New Chandra observations obtained for these objects show that their values of αox and Δαox, as well as their spectral energy distributions, are consistent with those of non- BAL quasars. Moreover, our targets have X-ray spectral shapes that are, on average, consistent with weakened absorption with an effective power-law photon index of Γeff = 1.69-0.25+0.25. The newer Gemini and ARC 3.5m spectra reveal that the BAL troughs have remained absent since the BOSS observations where the BAL disappearance was discovered. The X-ray and optical/UV results in tandem are consistent with at least the X-ray-absorbing material moving out of the line of sight, leaving an X-ray-unabsorbed non-BAL quasar. The UV absorber might have become more highly ionized (in a shielding-gas scenario) or also moved out of the line of sight (in a wind-clumping scenario).

KW - Galaxies: active

KW - Quasars: absorption lines

KW - Quasars: general

UR - https://www.scopus.com/pages/publications/85057171295

UR - https://www.scopus.com/pages/publications/85057171295#tab=citedBy

U2 - 10.1093/mnras/sty2718

DO - 10.1093/mnras/sty2718

M3 - Article

AN - SCOPUS:85057171295

SN - 0035-8711

VL - 482

SP - 1121

EP - 1134

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 1

ER -

X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations

Abstract

Keywords

ASJC Scopus subject areas

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