J/ApJ/898/62 Age & [Z/H] relations of SDSS star-forming galaxies (Barone+, 2020)
Gravitational potential and surface density drive stellar populations.
II. Star-forming Galaxies.
Barone T.M., D'Eugenio F., Colless M., Scott N.
<Astrophys. J., 898, 62 (2020)>
=2020ApJ...898...62B 2020ApJ...898...62B
ADC_Keywords: Galaxies, optical; Spectra, optical; Redshifts; Stars, masses;
Abundances
Keywords: Scaling relations ; Galaxy stellar content ; Galaxy ages ;
Galaxy abundances ; Extragalactic astronomy
Abstract:
Stellar population parameters correlate with a range of galaxy
properties, but it is unclear which relations are causal and which are
the result of another underlying trend. In this series, we
quantitatively compare trends between stellar population properties
and galaxy structural parameters in order to determine which relations
are intrinsically tighter, and are therefore more likely to reflect a
causal relation. Specifically, we focus on the galaxy structural
parameters of mass M, gravitational potential Φ∼M/Re, and
surface mass density Σ∼M/Re2. In Barone+ (Paper I;
2018ApJ...856...64B 2018ApJ...856...64B) we found that for early-type galaxies (ETGs) the
age-Σ and [Z/H]-Φ relations show the least intrinsic scatter
as well as the least residual trend with galaxy size. In this work we
study the ages and metallicities measured from full spectral fitting
of 2085 star-forming galaxies (SFGs) from the SDSS Legacy Survey,
selected so all galaxies in the sample are probed to one effective
radius. As with the trends found in ETGs, we find that in SFGs age
correlates best with stellar surface mass density, and [Z/H]
correlates best with gravitational potential. We discuss multiple
mechanisms that could lead to these scaling relations. For the
[Z/H]-Φ relation we conclude that gravitational potential is the
primary regulator of metallicity, via its relation to the gas escape
velocity. The age-Σ relation is consistent with compact galaxies
forming earlier, as higher gas fractions in the early universe cause
old galaxies to form more compactly during their in situ formation
phase, and may be reinforced by compactness-related quenching mechanisms.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 146 2085 Derived stellar population parameters
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/ApJ/621/673 : Line indices for 124 early-type galaxies (Thomas+, 2005)
J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)
J/ApJS/171/146 : Population synthesis in the blue. IV (Schiavon+, 2007)
J/MNRAS/382/109 : Massive galaxies in Extended Groth Strip (Trujillo+, 2007)
J/MNRAS/404/1639 : MILES base models & new line index system (Vazdekis+, 2010)
J/MNRAS/413/813 : ATLAS3D project. I. (Cappellari+, 2011)
J/ApJS/196/11 : Bulge+disk decompositions of SDSS galaxies (Simard+, 2011)
J/ApJ/749/121 : Surface brightness profiles if z=2 galaxies (Szomoru+, 2012)
J/ApJ/768/74 : PHIBSS: CO obs. of star-forming galaxies (Tacconi+, 2013)
J/MNRAS/440/843 : SIM2D parameters of SDSS-DR7 galaxies (Omand+, 2014)
J/ApJS/219/8 : SFR for WISE + SDSS spectroscopic galaxies (Chang+, 2015)
J/A+A/581/A103 : CALIFA survey across the Hubble sequence (Gonzalez+, 2015)
J/MNRAS/448/3484 : ATLAS3D Project. XXX (McDermid+, 2015)
J/MNRAS/476/1765 : MaNGA E and S galaxies properties (Li+, 2018)
J/ApJ/874/66 : MASSIVE survey. XII. Galaxy gradients (Greene+, 2019)
J/ApJ/883/78 : Column densities of CGM absorption lines (Pointon+, 2019)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- specObjID SDSS spectroscopic object identifier
21- 39 I19 --- ObjID SDSS photometric object identifier
41- 44 I4 --- Plate [266/2970] SDSS plate identifier
46- 50 I5 d MJD [51609/54592] Modified Julian Date
of observation
52- 54 I3 --- Fiber [1/640] SDSS fiber identifier
56- 65 F10.8 --- z [0.043/0.073] SDSS spectroscopic redshift
67- 73 F7.4 [Gyr] logAgeL [-1.33/1.1] log10 luminosity-weighted age
75- 80 F6.4 [Gyr] e_logAgeL [0.05/0.15] Uncertainty in logAgeL
82- 88 F7.4 [-] [Z/H]L [-2.2/0.12] Luminosity-weighted metallicity
90- 95 F6.4 [-] e_[Z/H]L [0.04/0.13] Uncertainty in [Z/H]L
97-102 F6.4 [Gyr] logAgeM [0.03/1.14] log10 mass-weighted age
104-109 F6.4 [Gyr] e_logAgeM [0.0961] Uncertainty in logAge_M
111-117 F7.4 [-] [Z/H]M [-2.11/0.26] Mass-weighted metallicity
119-124 F6.4 [-] e_[Z/H]M [0.1802] Uncertainty in [Z/H]M
126-133 F8.5 [Msun] logM* [9.4/10.4] log10 stellar mass from
Kauffmann+ (2003MNRAS.346.1055K 2003MNRAS.346.1055K)
135-141 F7.5 [Msun] e_logM* [0.05/0.31] Uncertainty in logM*
143-146 F4.2 kpc Re [1.12/2.35] Circularized effective radius
in r-band from Simard+ (2011, J/ApJS/196/11)
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History:
From electronic version of the journal
References:
Barone et al. Paper I. 2018ApJ...856...64B 2018ApJ...856...64B
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 17-Nov-2021