J/ApJ/857/126 Quasars Probing Quasars. IX. (QPQ9) (Lau+, 2018)
Quasars Probing Quasars.
IX. The kinematics of the circumgalactic medium surrounding z∼2 quasars.
Lau M.W., Prochaska J.X., Hennawi J.F.
<Astrophys. J., 857, 126-126 (2018)>
=2018ApJ...857..126L 2018ApJ...857..126L (SIMBAD/NED BibCode)
ADC_Keywords: QSOs; Spectra, optical; Redshifts; Ultraviolet;
Intergalactic medium
Keywords: galaxies: clusters: intracluster medium; galaxies: formation
galaxies: halos; intergalactic medium; quasars: absorption lines
quasars: general
Abstract:
We examine the kinematics of the gas in the environments of galaxies
hosting quasars at z∼2. We employ 148 projected quasar pairs to study
the circumgalactic gas of the foreground quasars in absorption. The
sample selects foreground quasars with precise redshift measurements,
using emission lines with precision ≲300km/s and average offsets from
the systemic redshift ≲|100km/s|. We stack the background quasar
spectra at the foreground quasar's systemic redshift to study the mean
absorption in C II, C IV, and Mg II. We find that the mean absorptions
exhibit large velocity widths σv∼300km/s. Further, the mean
absorptions appear to be asymmetric about the systemic redshifts. The
mean absorption centroids exhibit small redshift relative to the
systemic δv~+200km/s, with large intrinsic scatter in the
centroid velocities of the individual absorption systems. We find the
observed widths are consistent with gas in gravitational motion and
Hubble flow. However, while the observation of large widths alone does
not require galactic-scale outflows, the observed offsets suggest that
the gas is on average outflowing from the galaxy. The observed offsets
also suggest that the ionizing radiation from the foreground quasars
is anisotropic and/or intermittent.
Description:
We have collected a sample of 148 background spectra that are paired
with foreground quasars with precisely measured redshifts. Among the
sightlines in the QPQ9 sample, 13 have spectral resolution R>5000 from
echellette or echelle observations, and have been analyzed separately
in QPQ8 (Lau+ 2016ApJS..226...25L 2016ApJS..226...25L ; see their Figures 8-10 and their
Appendix).
We adopt a ΛCDM cosmology with ΩM=0.26,
ΩΛ=0.74, and H0=70km/s/Mpc.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 79 148 Properties of the projected quasar pairs
in the QPQ9 sample
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See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
VII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)
J/AJ/130/381 : Blueshifted [O III] emission (Boroson+, 2005)
J/ApJ/651/61 : Optically thick absorbers near luminous QSOs (Hennawi+, 2006)
J/MNRAS/391/1457 : Lymanα forest in QSO pairs (Kirkman+, 2008)
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/ApJ/740/91 : Lyα and OVI in galaxies around quasars (Prochaska+, 2011)
J/ApJ/762/L19 : Quasar pairs spectroscopy (Prochaska+, 2013)
J/MNRAS/430/425 : VLT LBG Redshift Survey. III. (Bielby+, 2013)
J/ApJ/776/136 : QPQ VI. HI absorption of z∼2 quasars (Prochaska+, 2013)
J/ApJ/794/156 : MgII/FeII absorption profile for 0.3<z<1.4 gal. (Rubin+, 2014)
J/ApJ/796/140 : Circumgalactic medium surrounding z∼2 QSOs (Prochaska+, 2014)
J/MNRAS/452/2553 : Sample of foreground-background QSO pairs (Johnson+, 2015)
J/ApJ/818/30 : Lag measurements for 15 z<0.8 QSOs from SDSS-RM (Shen+, 2016)
J/ApJ/831/7 : SDSS-RM project: peak velocities of QSOs (Shen+, 2016)
J/MNRAS/462/3285 : XQ-100. X-shooter quasar spectra (Perrotta+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- QSOfg Foreground quasar designation
(JHHMMSS.ss+DDMMSS.s)
21- 26 F6.4 --- zfg [1.6/3.82] Foreground redshift
28- 34 A7 --- n_zfg The emission line analyzed for measuring zfg
36- 54 A19 --- QSObg Background quasar designation
(JHHMMSS.ss+DDMMSS.s)
56- 60 F5.3 --- zbg [1.64/4.2] Background redshift
62- 69 A8 --- Telzbg Background quasar instrument
71- 73 I3 kpc Sep [32/299] Projected separation at the foreground
quasar's redshift
75- 79 I5 --- gUV [60/34208] The enhancement in the UV flux
relative to the extragalactic UV background,
gUV
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History:
From electronic version of the journal
References:
Hennawi et al. Paper I. 2006ApJ...651...61H 2006ApJ...651...61H Cat. J/ApJ/651/61
Hennawi & Prochaska Paper II. 2007ApJ...655..735H 2007ApJ...655..735H
Prochaska & Hennawi Paper III. 2009ApJ...690.1558P 2009ApJ...690.1558P
Hennawi & Prochaska Paper IV. 2013ApJ...766...58H 2013ApJ...766...58H
Prochaska et al. Paper V. 2013ApJ...762L..19P 2013ApJ...762L..19P Cat. J/ApJ/762/L19
Prochaska et al. Paper VI. 2013ApJ...776..136P 2013ApJ...776..136P Cat. J/ApJ/776/136
Prochaska et al. Paper VII. 2014ApJ...796..140P 2014ApJ...796..140P Cat. J/ApJ/796/140
Lau et al. Paper VIII. 2016ApJS..226...25L 2016ApJS..226...25L
Lau et al. Paper IX. 2018ApJ...857..126L 2018ApJ...857..126L This catalog
Findlay et al. Paper X. 2018ApJS..236...44F 2018ApJS..236...44F
(End) Emmanuelle Perret [CDS] 28-Sep-2023