J/MNRAS/493/87 1005 galaxies with z<0.09 sample (Trujillo+, 2020)
A physically motivated definition for the size of galaxies in an era of
ultradeep imaging.
Trujillo I., Chamba N., Knapen J.H.
<Mon. Not. R. Astron. Soc., 493, 87-105 (2020)>
=2020MNRAS.493...87T 2020MNRAS.493...87T (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Photometry, SDSS ; Redshifts ; Morphology
Keywords: methods: data analysis - methods: observational -
techniques: photometric - galaxies: formation -
galaxies: fundamental parameters - galaxies: photometry
Abstract:
Present-day multiwavelength deep imaging surveys allow to characterize
the outskirts of galaxies with unprecedented precision. Taking
advantage of this situation, we define a new physically motivated
measurement of size for galaxies based on the expected location of the
gas density threshold for star formation. Employing both theoretical
and observational arguments, we use the stellar mass density contour
at 1M_☉/pc2 as a proxy for this density threshold for star
formation. This choice makes our size definition operative. With this
new size measure, the intrinsic scatter of the global stellar mass
(M*)-size relation (explored over five orders of magnitude in
stellar mass) decreases to ∼0.06dex. This value is 2.5 times
smaller than the scatter measured using the effective radius
(∼0.15dex) and between 1.5 and 1.8 times smaller than those using
other traditional size indicators such as R23.5,i (∼0.09dex), the
Holmberg radius RH (∼0.09dex), and the half-mass radius Re,M*
(∼0.11dex). Moreover, galaxies with 107M☉<M*<1011^M☉
increase monotonically in size following a power law with a slope very
close to 1/3, equivalent to an average stellar mass 3D density of
∼4.5x10-3M☉/pc^3% for galaxies within this mass range.
Galaxies with M*>1011M☉ show a different slope with stellar
mass, which is suggestive of a larger gas density threshold for star
formation at the epoch when their star formation peaks.
Description:
We have selected 1005 galaxies with z<0.09 spanning five orders of
magnitude in stellar mass (107M☉<M*<1012M☉). This
collection of galaxies extends from the dwarf galaxies regime up to
giant spirals and ellipticals.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 119 1005 Characteristics of the galaxies used in this work
--------------------------------------------------------------------------------
See also:
J/ApJS/186/427 : Detailed morphology of SDSS galaxies (Nair+, 2010)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 20 A20 --- ID Identifier (JHHMMSS.ss+DDMMSS.ss) (1)
22- 30 F9.5 deg RAdeg Right ascension (J2000) (1)
32- 39 F8.5 deg DEdeg Declination (J2000) (1)
41- 44 F4.2 --- q Axial ratio
46- 52 F7.2 deg PA [] Position angle (measured counter-clockwise
starting from the horizontal axis)
54- 58 F5.3 mag Ag Galactic extinctions in the g band
60- 64 F5.3 mag Ar Galactic extinctions in the r band
66- 70 F5.3 mag Ai Galactic extinctions in the i band
72- 77 F6.4 --- z Spectroscopic redshift (1)
79- 81 I3 --- TType Morphological type (2)
83- 88 F6.2 kpc Re Effective radius (measured in the g-band)
90- 94 F5.2 kpc RhalfMass Half-mass radius
96-100 F5.2 kpc R235i Radius corresponding to the location of the
isophote with µi=23.5mag/arcsec2
102-106 F5.2 kpc RH Holmberg radius
108-113 F6.2 kpc R1 Radial location of the isomass contour at
1M_☉/pc2
115-119 F5.2 [Msun] logM* Stellar mass of galaxies
(assuming a Chabrier IMF)
--------------------------------------------------------------------------------
Note (1): from Abolfathi et al., 2018ApJS..235...42A 2018ApJS..235...42A
Note (2): from Nair & Abraham (2010ApJS..186..427N 2010ApJS..186..427N, Cat. J/ApJS/186/427).
TType = -99 corresponds to dwarf galaxies.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 31-Aug-2023