J/ApJ/931/51 Subaru/HSC imaging of SQuIGGLE z∼0.7 galaxies (Setton+, 2022)
The compact structures of massive z∼0.7 post-starburst galaxies in the SQuIGGLE.
Setton D.J., Verrico M., Bezanson R., Greene J.E., Suess K.A.,
Goulding A.D., Spilker J.S., Kriek M., Feldmann R., Narayanan D.,
Hall-Hooper K., Kado-Fong E.
<Astrophys. J., 931, 51 (2022)>
=2022ApJ...931...51S 2022ApJ...931...51S
ADC_Keywords: Galaxies, optical; Redshifts; Morphology; Galaxies, radius;
Surveys
Keywords: Post-starburst galaxies ; Galaxy quenching ; Galaxy evolution ;
Quenched galaxies ; Galaxies
Abstract:
We present structural measurements of 145 spectroscopically selected
intermediate-redshift (z∼0.7), massive (M*∼1011M☉)
post-starburst galaxies from the SQuIGG->LE sample measured using
wide-depth Hyper Suprime-Cam i-band imaging. This deep imaging allows
us to probe the sizes and structures of these galaxies, which we
compare to a control sample of star-forming and quiescent galaxies
drawn from the LEGA-C Survey. We find that post-starburst galaxies
systematically lie ∼0.1dex below the quiescent mass-size (half-light
radius) relation, with a scatter of ∼0.2dex. This finding is bolstered
by nonparametric measures, such as the Gini coefficient and the
concentration, which also reveal these galaxies to have more compact
light profiles than both quiescent and star-forming populations at
similar mass and redshift. The sizes of post-starburst galaxies show
either negative or no correlation with the time since quenching, such
that more recently quenched galaxies are larger or similarly sized.
This empirical finding disfavors the formation of post-starburst
galaxies via a purely central burst of star formation that
simultaneously shrinks the galaxy and shuts off star formation. We
show that the central densities of post-starburst and quiescent
galaxies at this epoch are very similar, in contrast with their
effective radii. The structural properties of z∼0.7 post-starburst
galaxies match those of quiescent galaxies that formed in the early
universe, suggesting that rapid quenching in the present epoch is
driven by a similar mechanism to the one at high redshift.
Description:
The SQuIGGLE sample (Suess+ 2022, J/ApJ/926/89) is selected from the
SDSS DR14 spectroscopic sample (Abolfathi+ 2018ApJS..235...42A 2018ApJS..235...42A);
see Section 2.1 and the LEGA-C Survey DR3
(van der Wel+ 2021, J/ApJS/256/44); see Section 2.2.
Using i-band images from the HSC survey, we study the sizes and
structures of z∼0.7 post-starburst galaxies. See Section 2.3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 130 145 Structural and selected spectrophotometric
properties of SQuIGGLE post-starburst galaxies
table2.dat 94 145 Uncertainties on Sersic parameters from PSF model
refitting
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See also:
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/ApJ/588/218 : i*g* photometry of SDSS EDR galaxies (Abraham+, 2003)
J/ApJS/147/1 : Classification of nearby galaxies (Conselice+, 2003)
J/ApJ/749/121 : Surface brightness profiles if z=2 galaxies (Szomoru+, 2012)
J/ApJS/203/24 : Structural param. of galaxies in CANDELS (van der Wel+, 2012)
J/ApJ/777/18 : Stellar mass functions of galaxies to z=4 (Muzzin+, 2013)
J/ApJ/833/19 : 0.02<z<1.4 post-starburst SDSS gal. (Pattarakijwanich+, 2016)
J/ApJ/862/2 : Post-starburst galaxy ages from SDSS (French+, 2018)
J/ApJ/877/103 : Half-mass radii for ∼7000 gal. at 1.0≤z≤2.5 (Suess+, 2019)
J/ApJ/919/134 : SDSS shocked post-starburst gal. with HST (Sazonova+, 2021)
J/ApJS/256/44 : LEGA-C DR3: spectroscopy of 0.6<z<1 gal. (van der Wel+, 2021)
J/ApJ/923/222 : GCLASS HST grism data of z∼1 clusters (Matharu+, 2021)
J/ApJ/926/89 : SQuIGGLE; SDSS 0.5<z≤0.9 post-starburst gal. (Suess+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name SQuIGGLE galaxy name, JHHMM±DDMM
12- 20 F9.5 deg RAdeg Right Ascension (J2000)
22- 31 F10.7 deg DEdeg [-7/45] Declination (J2000)
33- 38 F6.4 --- zspec [0.54/0.9] Spectroscopic redshift
40- 44 F5.2 [Msun] logM16 [10.68/11.54] Log, stellar mass, 16th
percentile (1)
46- 50 F5.2 [Msun] logM50 [10.7/11.6] Log, stellar mass, 50th
percentile (1)
52- 56 F5.2 [Msun] logM84 [10.7/11.62] Log, stellar mass, 84th
percentile (1)
58- 62 F5.2 kpc re [0.78/12.3] Effective Sersic radius (2)
64- 68 F5.2 kpc reCorr [0.76/10.8] Residual-corrected
effective radii (3)
70- 73 F4.2 --- n [0.79/6] Sersic parameter (2)
75- 79 F5.2 mag mag [18.3/21.1] Sersic magnitude (2)
81- 84 F4.2 --- b/a [0.35/0.99] Sersic axis ratio (2)
86- 90 F5.2 [Msun/kpc2] logSig1 [9.38/10.8] Log of surface density at
1kpc
92- 95 F4.2 --- Gini [0.4/0.8] Gini coefficient (4)
97- 100 F4.2 --- Conc [2/3.4] Generalized concentration (4)
102- 105 F4.2 Gyr tq16 [0.01/0.6]? Time since quenching, 16th
percentile (5)
107- 110 F4.2 Gyr tq50 [0.02/0.8]? Time since quenching, 50th
percentile (5)
112- 115 F4.2 Gyr tq84 [0.03/1.3]? Time since quenching, 84th
percentile (5)
117- 120 F4.2 --- fBurst16 [0.02/0.8]? Burst fraction, 16th
percentile (5)
122- 125 F4.2 --- fBurst50 [0.02/1]? Burst fraction, 50th
percentile (5)
127- 130 F4.2 --- fBurst84 [0.03/1]? Burst fraction, 84th
percentile (5)
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Note (1): Stellar masses were derived using a delayed-exponential star
formation history, described in Section 2.1
Note (2): Sersic parameters were derived using single-component 2D Sersic
models to fit the galaxies of interest. Uncertainties derived by refitting
the galaxies using a range of PSF models from nearby locations on the sky
are shown in Table 2. For details, see Section 3.1.
Note (3): The residual-corrected effective radii were derived using the method
of Szomoru+ 2012, J/ApJ/749/121, described in Section 3.3.
Note (4): The Gini coefficient (G) and the generalized concentration (GC) were
measured on the segmentation maps described in Section 3.1, for details
see Section 4.3.
Note (5): Time since quenching (tq) and the burst fraction are model parameters
derived from non-parametric star formation history fitting of the galaxies,
see Suess+ 2022, J/ApJ/926/89 for details.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name SQuIGGLE galaxy name, JHHMM±DDMM
12- 16 F5.2 kpc re16 [0.76/12.6] Effective Sersic radius,
kpc, 16th percentile
18- 22 F5.2 kpc re50 [0.97/13] Effective Sersic radius,
kpc, 50th percentile
24- 28 F5.2 kpc re84 [1/13.3] Effective Sersic radius,
kpc, 84th percentile
30- 33 F4.2 --- n16 [0.8/6] Sersic parameter, 16th
percentile
35- 38 F4.2 --- n50 [0.88/6] Sersic parameter, 50th
percentile
40- 43 F4.2 --- n84 [1.2/6] Sersic parameter, 84th
percentile
45- 49 F5.2 mag mag16 [18.29/21.1] Sersic magnitude, 16th
percentile
51- 55 F5.2 mag mag50 [18.3/21.2] Sersic magnitude, 50th
percentile
57- 61 F5.2 mag mag84 [18.35/21.2] Sersic magnitude, 84th
percentile
63- 66 F4.2 --- b/a16 [0.19/0.96] Sersic axis ratio, b/a,
16th percentile
68- 71 F4.2 --- b/a50 [0.3/0.98] Sersic axis ratio, b/a,
50th percentile
73- 76 F4.2 --- b/a84 [0.39/0.99] Sersic axis ratio, b/a,
84th percentile
78- 82 F5.2 [Msun/kpc2] logSig1-16 [9/10.3] Log, surface density at
1kpc, Msun/kpc2, 16th percentile
84- 88 F5.2 [Msun/kpc2] logSig1-50 [9/10.3] Log, surface density at
1kpc, Msun/kpc2, 50th percentile
90- 94 F5.2 [Msun/kpc2] logSig1-84 [9.2/10.5] Log, surface density at
1kpc, Msun/kpc2, 84th percentile
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 21-Mar-2024