J/ApJ/701/1219 Galaxy survey in 3 QSO fields (Chen+, 2009)
Probing the intergalactic medium-galaxy connection at z < 0.5.
I. A galaxy survey in QSO fields and a galaxy-absorber cross-correlation study.
Chen H.-W., Mulchaey J.S.
<Astrophys. J., 701, 1219-1242 (2009)>
=2009ApJ...701.1219C 2009ApJ...701.1219C
ADC_Keywords: Galaxies, spectra ; Photometry, UBVRI ; Redshifts ; Surveys ; QSOs
Keywords: cosmology: observations - intergalactic medium -
quasars: absorption lines
Abstract:
We present an imaging and spectroscopic survey of galaxies in fields
around QSOs HE 0226-4110, PKS 0405-123, and PG 1216+069. The fields
are selected to have ultraviolet echelle spectra available, which
uncover 195 Lyα absorbers and 13 OVI absorbers along the three
sightlines. We obtain robust redshifts for 1104 galaxies of rest-frame
absolute magnitude MR-5logh≲-16 and at projected physical distances
ρ≲4h-1Mpc from the QSOs. Hubble Space Telescope (HST)/WFPC2
images of the fields around PKS 0405-123 and PG 1216+069 are
available for studying the optical morphologies of absorbing galaxies.
Combining the absorber and galaxy data, we perform a cross-correlation
study to understand the physical origin of Lyα and OVI absorbers
and to constrain the properties of extended gas around galaxies.
Description:
The observing program of the galaxy survey consists of three phases:
(1) imaging observations of the QSO fields to identify candidate
galaxies: optical images of the field around HE 0226-4110 were
obtained on 2004 September 19, using the IMACS short camera and the B,
R, and I filters on the Magellan Baade Telescope. Optical images of
the field around PG 1216+069 were obtained on 2005 March 19, using the
IMACS short camera and the B, R, and I filters; and additional optical
images of PKS 0405-123 and PG1216+069 were obtained from the HST data
archive for the Wide Field and Planetary Camera2 (WFPC2) with the
F702W filter; (2) object selection for follow-up faint galaxy
spectroscopy; and (3) multislit spectroscopic observations, using
IMACS and the short camera during three different runs in 2004
November, 2006 May, and 2007 April, to measure the redshifts of the
selected galaxies.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 27 66 Lyα absorbers identified along the
sightline toward PG 1216+069
table4.dat 116 1793 Photometric and spectroscopic catalog of objects
in the field around HE0226-4110
table5.dat 116 1379 *Photometric and spectroscopic catalog of objects
in the field around PKS0405-123
table6.dat 116 1619 Photometric and spectroscopic catalog of objects
in the field around PG1216+069
--------------------------------------------------------------------------------
Notes on table5.dat: The object ID, coordinates, and R-band photometry are
adopted from Prochaska et al. (2006, Cat. J/ApJ/643/680).
--------------------------------------------------------------------------------
See also:
J/ApJ/679/194 : Low-z intergalactic medium. III. (Danforth+, 2008)
J/ApJ/643/680 : Imaging and spectroscopy around PKS 0405-123 (Prochaska+, 2006)
J/ApJ/617/718 : Atomic data and EW for PKS 0405-123 (Prochaska+, 2004)
J/ApJ/508/200 : QSO low-z Lyα absorbers (Tripp+, 1998)
J/A+A/316/123 : QSO absorber and galaxy evolution (Lindner+ 1996)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.5 --- z Lyα absorber redshift
8- 10 A3 --- f_z [ab, ] Flag on z (1)
12- 16 F5.2 [cm-2] logNHI HI column density
18- 21 F4.2 [cm-2] e_logNHI logNHI uncertainty
23- 24 I2 km/s b ? Doppler impact parameter b
26- 27 I2 km/s e_b ? b uncertainty
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = The measurement is adopted from Tripp et al. (2005ApJ...619..714T 2005ApJ...619..714T).
b = These lines have also been identified by Jannuzi et al.
(1998ApJS..118....1J 1998ApJS..118....1J) in low-resolution data obtained using the Faint
Object Spectrograph.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table[456].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- ID Identification number
(see the "Nomenclature Notes" section below)
6 A1 --- r_z [IP] origin of z (table5 only) (1)
8- 9 I2 h RAh Hour of Right Ascension (J2000)
11- 12 I2 min RAm Minute of Right Ascension (J2000)
14- 19 F6.3 s RAs Second of Right Ascension (J2000)
21 A1 --- DE- Sign of the Declination (J2000)
22- 23 I2 deg DEd Degree of Declination (J2000)
25- 26 I2 arcmin DEm Arcminute of Declination (J2000)
28- 32 F5.2 arcsec DEs Arcsecond of Declination (J2000)
34- 39 F6.1 arcsec offRA Offset in Right Ascension from QSO
41- 46 F6.1 arcsec offDE Offset in Declination from QSO
48- 52 F5.1 arcsec Sep Angular distance to QSO
54- 60 F7.2 kpc Dist ?=-1 Projected physical distance in units
of h-1kpc
62- 67 F6.3 mag Bmag ? B band magnitude (not for table 5)
69- 73 F5.3 mag e_Bmag ? Uncertainty in Bmag
75- 80 F6.3 mag Rmag R band magnitude
82- 86 F5.3 mag e_Rmag Uncertainty in Rmag
88- 93 F6.3 mag Imag ? I band magnitude (not for table 5)
95- 99 F5.3 mag e_Imag ? Uncertainty in Imag
101-107 F7.4 --- z ?=-1 Spectroscopic redshift
109 I1 --- Type [1,2]?=0 absorption or emission galaxy (2)
111-116 F6.2 mag RMag ?=0 Rest-frame R band absolute band magnitude (3)
--------------------------------------------------------------------------------
Note (1): Code as follows:
I = New Spectroscopic redshifts obtained in our survey.
P = Spectroscopic redshifts published in Prochaska et al., Cat. J/ApJ/643/680
Note (2): Code as follows:
1 = absorption-line dominated;
2 = emission-line dominated.
Note (3): The rest-frame R band magnitude of each spectroscopically
identified object was estimated based on the observed R band magnitude
and spectral type. For absorption-line dominated galaxies, we
evaluate the k-correction using the early-type E/S0 and Sab galaxy
templates from Coleman et al. (1980ApJS...43..393C 1980ApJS...43..393C). For emission-line
dominated galaxies, we evaluate the k-correction using the Irr templates.
--------------------------------------------------------------------------------
Nomenclature Notes:
For table 3, absorbers are <[CM2009b] PG1216+069 abs N.NNNNN> in the
Dictionary of Nomenclature.
For table 4, galaxies are <[CM2009b] HE0226-4110 NNNNN> in Simbad.
For table 5, galaxies are <[PWC2006b] NNNNN> for Simbad.
For table 6, galaxies are <[CM2009b] PG1216+069 NNNNN> in Simbad.
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Sep-2011