J/ApJ/960/34 Quasars from DESI SV data in the COSMOS/HSC fields (Zou+, 2024)
DESI Survey Validation data in the COSMOS/Hyper Suprime-Cam field: cool gas
trace main-sequence star-forming galaxies at the Cosmic noon.
Zou S., Jiang L., Cai Z., Moustakas J., Sun Z., Pan Z., Ding J.,
Forero-Romero J.E., Zou Hu, Ting Y.-S., Pieri M., Ahlen S., Alexander D.,
Brooks D., Dey A., Font-Ribera A., Gontcho Gontcho S. A, Honscheid K.,
Landriau M., de la Macorra A., Vargas Magana M., Meisner A., Miquel R.,
Schubnell M., Tarle G., Zhou Z.
<Astrophys. J., 960, 34 (2024)>
=2024ApJ...960...34Z 2024ApJ...960...34Z
ADC_Keywords: QSOs; Spectra, optical; Surveys; Redshifts; Equivalent widths;
Intergalactic medium
Keywords: Circumgalactic medium ; Galaxy environments ; Star formation ;
Quasar absorption line spectroscopy
Abstract:
We present the first result in exploring the gaseous halo and galaxy
correlation using the Dark Energy Spectroscopic Instrument survey
validation data in the Cosmic Evolution Survey (COSMOS) and Hyper
Suprime-Cam field. We obtain multiphase gaseous halo properties in the
circumgalactic medium by using 115 quasar spectra (signal-to-noise
ratio > 3). We detect MgII absorption at redshift 0.6<z<2.5, CIV
absorption at 1.6<z<3.6, and HI absorption associated with the MgII
and CIV. By crossmatching the COSMOS2020 catalog, we identify the MgII
and CIV host galaxies in 10 quasar fields at 0.9<z<3.1. We find that
within the impact parameter of 250kpc, a tight correlation is seen
between the strong MgII equivalent width and the host galaxy star
formation rate. The covering fraction fc of the strong MgII selected
galaxies, which is the ratio of the absorbing galaxy in a certain
galaxy population, shows significant evolution in the main-sequence
galaxies and marginal evolution in all the galaxy populations within
250kpc at 0.9<z<2.2. The fc increase in the main-sequence galaxies
likely suggests the coevolution of strong MgII absorbing gas and the
main-sequence galaxies at the cosmic noon. Furthermore, MgII and CIV
absorbing gas is detected out of the galaxy virial radius, tentatively
indicating the feedback produced by the star formation and/or the
environmental effects.
Description:
This project is a Dark Energy Spectroscopic Instrument (DESI)
secondary program in the survey validation (SV;
Myers+ 2023AJ....165...50M 2023AJ....165...50M). The quasars are selected from the
overlapping region of the COSMOS and HSC ultradeep fields (2deg2 and
having the tangent point R.A., decl. at 150.116, 2.210). The
observations of quasars in this work were conducted at Kitt Peak by
DESI between 2021 March and May. The average effective exposure time
is around 5.5hr.
Among the 114 selected quasars, 30 quasars are included in the quasar
catalog of SDSS DR16 (Lyke+ 2020, VII/289) and the other 84 are new
quasars.
The DESI spectra resolution at 3600-9800Å ranges from 2000 to 5000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 56 114 Quasars used in this work
tablea2.dat 67 78 Metal absorber measurements
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See also:
VII/289 : SDSS quasar catalog, sixteenth data release (DR16Q) (Lyke+, 2020)
J/MNRAS/371/495 : Catalog of 1806 MgII absorbers from SDSS DR3 (Bouche+, 2006)
J/ApJ/639/766 : SDSS-DR3 strong MgII absorbers (Prochter+, 2006)
J/ApJ/714/1521 : Spectroscopy of galaxies around distant QSOs (Chen+, 2010)
J/ApJ/724/L176 : MgII absorbing gas around galaxies (Chen+, 2010)
J/A+A/530/A50 : Principal Component Analysis of QSO UV sp. (Paris+, 2011)
J/ApJ/755/89 : Metallicities of damped Lyα systems (Rafelski+, 2012)
J/ApJ/779/87 : MAGIICAT. III. Virial masses (Churchill+, 2013)
J/ApJ/776/114 : MAGIICAT. I. MgII Absorber-Galaxy Catalog (Nielsen+, 2013)
J/ApJS/224/24 : The COSMOS2015 catalog (Laigle+, 2016)
J/ApJ/853/95 : Galaxies probing galaxies in PRIMUS. I. (Rubin+, 2018)
J/A+A/616/A158 : z>1.5 QSO VLT-XSHOOTER spectra (Zou+, 2018)
J/MNRAS/485/1961 : List of 22 MEGAFLOW fields (Zabl+, 2019)
J/MNRAS/499/5022 : MUSE Analysis of Gas around Galaxies II (Dutta+, 2020)
J/MNRAS/508/4573 : Galaxy surveys in quasars fields (Dutta+, 2021)
J/MNRAS/502/4743 : Census of circumgalactic MgII at z=<0.5 (Huang+, 2021)
J/ApJS/258/11 : The COSMOS2020 catalog (Weaver+, 2022)
J/ApJS/269/27 : DESI z≳5 quasar survey. I. New z∼4.7-6.6 QSOs (Yang+, 2023)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Quasar name (JHHMMSS.ss+DDMMSS.ss)
22- 27 F6.4 --- zem [0.6/4.1] Quasar emission redshift
29- 36 F8.4 deg RAdeg [148.6/151.7] Right ascension (J2000)
38- 43 F6.4 deg DEdeg [0.6/3.92] Declination (J2000)
45- 53 F9.3 s Exp [2884.4/22884.5] Quasar effective exposure time
55- 56 I2 --- S/N [1/70] Mean signal-to-noise ratio measured from
the three continuum regions without obvious
emission or absorption
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Quasar name (JHHMMSS.ss+DDMMSS.ss)
22- 27 F6.4 --- zabs [0.66/3.2] Absorber redshift
29- 35 F7.3 km/s dVMgII [119.6/785.5]? Velocity width of
MgII(λ2796) line
37- 41 F5.3 0.1nm EWMgII [0.27/5]? Equivalent width of
MgII(λ2796) line
43- 47 F5.3 0.1nm e_EWMgII [0.03/0.8]? EWMgII uncertainty
49- 55 F7.3 km/s dVCIV [152.9/977]? Velocity width of
CIV(λ1548) line
57- 61 F5.3 0.1nm EWCIV [0.2/3.1]? Equivalent width of
CIV(λ1548) line
63- 67 F5.3 0.1nm e_EWCIV [0.04/1]? EWCIV uncertainty
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 06-Mar-2026