C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS

C. J. Grier, William Nielsen Brandt, P. B. Hall, J. R. Trump, N. Filiz Ak, S. F. Anderson, Paul J. Green, Donald P. Schneider, M. Sun, M. Vivek, Thomas Beatty, Joel R. Brownstein, Alexandre Roman-Lopes

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5-5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3% of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.

Original languageEnglish (US)
Article number130
JournalAstrophysical Journal
Volume824
Issue number2
DOIs
StatePublished - Jun 20 2016

Fingerprint

quasars
deceleration
shift
troughs
trough
signatures
line of sight
projection
galaxies
timescale
radii
profiles
gases
gas

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Grier, C. J., Brandt, W. N., Hall, P. B., Trump, J. R., Filiz Ak, N., Anderson, S. F., ... Roman-Lopes, A. (2016). C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS. Astrophysical Journal, 824(2), [130]. https://doi.org/10.3847/0004-637X/824/2/130
Grier, C. J. ; Brandt, William Nielsen ; Hall, P. B. ; Trump, J. R. ; Filiz Ak, N. ; Anderson, S. F. ; Green, Paul J. ; Schneider, Donald P. ; Sun, M. ; Vivek, M. ; Beatty, Thomas ; Brownstein, Joel R. ; Roman-Lopes, Alexandre. / C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS. In: Astrophysical Journal. 2016 ; Vol. 824, No. 2.
@article{aa3fe2af8e224a818db4cca6f567f2b8,
title = "C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS",
abstract = "We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5-5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3{\%} of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.",
author = "Grier, {C. J.} and Brandt, {William Nielsen} and Hall, {P. B.} and Trump, {J. R.} and {Filiz Ak}, N. and Anderson, {S. F.} and Green, {Paul J.} and Schneider, {Donald P.} and M. Sun and M. Vivek and Thomas Beatty and Brownstein, {Joel R.} and Alexandre Roman-Lopes",
year = "2016",
month = "6",
day = "20",
doi = "10.3847/0004-637X/824/2/130",
language = "English (US)",
volume = "824",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",

}

Grier, CJ, Brandt, WN, Hall, PB, Trump, JR, Filiz Ak, N, Anderson, SF, Green, PJ, Schneider, DP, Sun, M, Vivek, M, Beatty, T, Brownstein, JR & Roman-Lopes, A 2016, 'C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS', Astrophysical Journal, vol. 824, no. 2, 130. https://doi.org/10.3847/0004-637X/824/2/130

C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS. / Grier, C. J.; Brandt, William Nielsen; Hall, P. B.; Trump, J. R.; Filiz Ak, N.; Anderson, S. F.; Green, Paul J.; Schneider, Donald P.; Sun, M.; Vivek, M.; Beatty, Thomas; Brownstein, Joel R.; Roman-Lopes, Alexandre.

In: Astrophysical Journal, Vol. 824, No. 2, 130, 20.06.2016.

Research output: Contribution to journalArticle

TY - JOUR

T1 - C IV BROAD ABSORPTION LINE ACCELERATION in SLOAN DIGITAL SKY SURVEY QUASARS

AU - Grier, C. J.

AU - Brandt, William Nielsen

AU - Hall, P. B.

AU - Trump, J. R.

AU - Filiz Ak, N.

AU - Anderson, S. F.

AU - Green, Paul J.

AU - Schneider, Donald P.

AU - Sun, M.

AU - Vivek, M.

AU - Beatty, Thomas

AU - Brownstein, Joel R.

AU - Roman-Lopes, Alexandre

PY - 2016/6/20

Y1 - 2016/6/20

N2 - We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5-5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3% of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.

AB - We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5-5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3% of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.

UR - http://www.scopus.com/inward/record.url?scp=84978229781&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84978229781&partnerID=8YFLogxK

U2 - 10.3847/0004-637X/824/2/130

DO - 10.3847/0004-637X/824/2/130

M3 - Article

VL - 824

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 130

ER -