J/A+A/695/A207 BEINGMgII. II. Galaxies with strong MgII absorbers (Das+, 2025)
Baryonic Ecosystem IN Galaxies (BEINGMgII).
II. Unveiling the nature of galaxies harboring cool gas reservoirs.
Das S., Joshi R., Chaudhary R., Fumagalli M., Fossati M., Peroux C., Ho L.C.
<Astron. Astrophys. 695, A207 (2025)>
=2025A&A...695A.207D 2025A&A...695A.207D (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Galaxies, optical ; Galaxies, spectra
Keywords: galaxies: evolution - galaxies: general - galaxies: halos -
galaxies: high-redshift - quasars: absorption lines -
galaxies: star formation
Abstract:
We search for the galaxies associated with the intervening MgII
absorbers over a redshift range of 0.4≤z≤1 using imaging data from
DESI Legacy Imaging Surveys and measure the redshift based on direct
detection of nebular emission in the background quasar spectra from
SDSS survey. We find 270 MgII absorbers associated with strong [OII]
or, [OIII] and Hβnebular emissions, at 2.5σ level. Among
them, for 213 MgII absorbers, we detect an absorber host galaxy at
impact parameters of 4≤ρ≤16kpc, including three absorbers
associated with a galaxy pair, with best-fit galaxy SED model based on
multi-passband photometric data from DESI Legacy Imaging surveys,
supplemented with the infrared VISTA and unWISE imaging surveys. The
detection rate of MgII absorber host with strong [OII] nebular
emission in the finite SDSS fiber of 2-3 arcsec diameter increases
from 0.2% to ∼3% with increasing equivalent width from 0.3Å to
∼3.5Å, which remains near-constant across the probed redshift
range. The associated MgII host galaxies exhibit a wide range of
stellar mass from 7.94≤log(M*/M☉)≤11.11, with an average
star-formation rate (SFR) of 5.81M☉/yr. The MgII absorber hosts
selected based on [O II] nebular emission mostly exhibit active
star-forming systems including 13.4% starburst systems, but 10.2% with
suppressed SFR. The near-constant absorption strength at low-impact
parameters suggests a high gas covering fraction. We find that the
MgII equivalent width (W2796) positively correlates with SFR and
specific-SFR, likely indicating their wind origin. The average
velocity offset between the host and absorber suggests that the MgII
gas is bound within the dark matter halo.
Description:
This catalogue lists the properties of galaxies associated with strong
MgII absorbers in DECaLS Survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 130 273 Physical properties of galaxies associated
with strong MgII absorbers
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See also:
J/A+A/695/A206 : BEINGMgII. I. Galaxies with USMgII absorbers (Joshi+, 2025)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- QSO SDSS J2000 quasar name (JHHMMSS.ss+DDMMSS.s)
21- 26 F6.4 --- zabs MgII absorber redshift
28- 31 F4.2 0.1nm Wr2796 MgII 2796Å rest equivalent width
33- 36 F4.2 0.1nm e_Wr2796 Error on the MgII 2796Å
rest equivalent width
38- 41 F4.2 0.1nm Wr2803 MgII 2803Å rest equivalent width
43- 46 F4.2 0.1nm e_Wr2803 Error on the MgII 2803Å
rest equivalent width
48- 56 F9.5 deg RAdeg Galaxy right ascension (J2000)
58- 66 F9.5 deg DEdeg Galaxy declination (J2000)
68- 72 F5.2 kpc rho Impact parameter
74- 79 F6.2 [Msun] b_logMstar ?=-99.00 Stellar mass lower bound
81- 86 F6.2 [Msun] logMstar ?=-99.00 Stellar mass
88- 93 F6.2 [Msun] B_logMstar ?=-99.00 Stellar mass upper bound
95-102 E8.2 Msun/yr b_SFR ?=-99.00 Star formation rate lower bound
104-111 E8.2 Msun/yr SFR ?=-99.00 Star formation rate
113-120 E8.2 Msun/yr B_SFR ?=-99.00 Star formation rate upper bound
122-130 A9 --- Category Category (1)
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Note (1): Category as follows:
PRIMARY = Good SED Fit and detected [OII] nebular emission
SECONDARY = Only [OII] detected
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Acknowledgements:
Ravi Joshi, ravi.joshi(at)iiap.res.in
References:
Joshi et al., Paper I 2025A&A...695A.206J 2025A&A...695A.206J
(End) Ravi Joshi [Indian Inst. Astrophys.], Patricia Vannier [CDS] 24-Jan-2025