J/MNRAS/498/5885 SHαDE dwarf galaxies' mass and kinematics (Barat+, 2020)
SHαDE: survey description and mass-kinematics scaling relations for dwarf
galaxies.
Barat D., D'Eugenio F., Colless M., Sweet S.M., Groves B., Cortese L.
<Mon. Not. R. Astron. Soc., 498, 5885-5903 (2020)>
=2020MNRAS.498.5885B 2020MNRAS.498.5885B (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, dwarf ; Redshifts ; Galaxies, radius ;
Velocity dispersion ; Rotational velocities ; Stars, masses ;
Spectra, optical
Keywords: Galaxy kinematics and dynamics - Galaxy stellar content -
Galaxy structure
Abstract:
The Study of Hα from Dwarf Emissions (SHαDE) is a high
spectral resolution (R=13500) Hα integral field survey of 69
dwarf galaxies with stellar masses 106<M*<109M☉. The
survey used FLAMES on the ESO Very Large Telescope. SHαDE is
designed to study the kinematics and stellar populations of dwarf
galaxies using consistent methods applied to massive galaxies and at
matching level of detail, connecting these mass ranges in an unbiased
way. In this paper, we set out the science goals of SHαDE,
describe the sample properties, outline the data reduction, and
analysis processes. We investigate the logM*-logS0.5
mass-kinematics scaling relation, which has previously shown potential
for combining galaxies of all morphologies in a single scaling
relation. We extend the scaling relation from massive galaxies to
dwarf galaxies, demonstrating this relation is linear down to a
stellar mass of M*∼108.6M☉. Below this limit, the
kinematics of galaxies inside one effective radius appears to be
dominated by the internal velocity dispersion limit of the
Hα-emitting gas, giving a bend in the logM{*}-logS0.5
relation. Replacing stellar mass with total baryonic mass using gas
mass estimate reduces the severity but does not remove the linearity
limit of the scaling relation. An extrapolation to estimate the
galaxies' dark matter halo masses, yields a logMh-logS0.5 scaling
relation that is free of any bend, has reduced curvature over the
whole mass range, and brings galaxies of all masses and morphologies
on to the virial relation.
Description:
The SHαDE sample consists of 49 star-forming galaxies selected
form the Sloan Digital Sky Survey Data Release 12 (hereafter: SDSS;
Eisenstein et al. 2011AJ....142...72E 2011AJ....142...72E; Alam et al.
2015ApJS..219...12A 2015ApJS..219...12A, Cat. V/147), as well as 20 targets from the SAMI
survey as control sample. These targets are observed with high
spectral resolution IFU FLAMES instrument, and reduced with the
standard data reduction package. Other ancillary data are obtained
from the SDSS DR12.
We present new data from the FLAMES instrument at the 8m VLT Unit
Telescope 2 (Pasquini et al. 2002Msngr.110....1P 2002Msngr.110....1P), using the ARGUS IFU
and the GIRAFFE optical spectrograph. ARGUS is a rectangular array of
22x14 square microlenses; at the 1:1 scale, each microlens samples
0.52arcsec and the IFU FOV spans 11.4x7.3arcsec2. Light from
individual microlenses in the IFU is fed to GIRAFFE using optical
fibres. Besides the IFU itself, ARGUS also provides 15 dedicated sky
fibres, which can be placed anywhere inside the instrument FOV. Within
the slit, the fibres are arranged in 15 bundles, each consisting of 20
object fibres and a single sky fibre. On the detector, the fibres are
separated by 5.3 pixels, whereas the bundles are separated by 12-20
pixels.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 53 49 Summary of observations: the main sample
table2.dat 39 20 Summary of observations: the control sample,
drawn from SAMI
tablea1.dat 295 68 Quantities used in this work for analyses
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See also:
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/MNRAS/446/1567 : SAMI Galaxy Survey: EDR (Allen+, 2015)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID SHaDE identifier
5- 23 I19 --- Name SDSS SpObjID identifier
25- 29 F5.2 10-18W/m2/nm/arcsec2 fHa Hα flux from SDSS DR12
(Thomas, Maraston & Johansson
2011MNRAS.412.2183T 2011MNRAS.412.2183T)
31- 35 F5.2 10-18W/m2/nm/arcsec2 e_fHa Error on fHa
37- 41 A5 s Texp Exposure time
43- 46 F4.2 --- Median airmass
48- 51 F4.2 arcsec Seeing Median airmass-corrected seeing
53 A1 --- Run [A/B] Visitor Mode run (G1)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 I10 --- ID SHaDE/GAMA identifier
12- 16 F5.2 10-18W/m2/nm/arcsec2 fHa ? Hα flux
18- 21 F4.2 10-18W/m2/nm/arcsec2 e_fHa ? Error on fHa
23- 27 A5 s Texp Exposure time
29- 32 F4.2 --- Median airmass
34- 37 F4.2 arcsec Seeing Median airmass-corrected seeing
39 A1 --- Run [B/C] Mode run (G1)
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Byte-by-byte Description of file:tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 I10 --- ID SHaDE/GAMA identifier
12- 29 F18.14 deg RAdeg Right ascension (J2000)
31- 50 F20.16 deg DEdeg Declination (J2000)
52- 70 F19.16 arcsec Re Circularized half-light radius (1)
72- 92 F21.19 --- z Spectroscopic redshift from SDSS DR12
94- 112 F19.15 km/s sigma Velocity dispersion σ (2)
114- 133 F20.17 km/s e_sigma Error on sigma
135- 154 F20.16 km/s Vrot Rotation velocity Vrot (2)
156- 174 F19.16 km/s e_Vrot Error on Vrot
176- 194 F19.15 km/s S0.5 Kinematic parameter S0.5 (3)
196- 215 F20.17 km/s e_S0.5 Error on S0.5
217- 236 F20.17 [Msun/yr] logSFR ? Logarithm of the star formation rate from
SDSS DR12
238- 256 F19.16 [Msun] logM* Logarithm of the stellar mass (4)
258- 276 F19.16 [Msun] logMb ? Logarithm of the baryonic mass (5)
278- 295 F18.15 [Msun] logMh ? Logarithm of the halo mass (6)
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Note (1): Re is obtained from MGEFIT fitting using SDSS DR12 i-band photometry
Note (2): σ and Vrot are calculated in this work following recipe
outlined in Section 4.3
Note (3): The kinematic parameter S0.5 is calculated as:
S0.5=sqrt(0.5Vrot2+σ2)
Note (4): logM* is calculated using i-band magnitude and g-i colour following
Taylor et al. (2011MNRAS.418.1587T 2011MNRAS.418.1587T)
Note (5): logMb is estimated following Kennicutt (1998ApJ...498..541K 1998ApJ...498..541K) and is
outlined in Section 5.4
Note (6): logMh is estimated following Moster et al. (2010ApJ...710..903M 2010ApJ...710..903M) and
is outlined in Section 6.2
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Global Notes:
Note (G1): The observations were carried out under ESO program 0101.B-0505 in
two Visitor Mode runs (A and B), complemented by a Service Mode run
(C) allocated as time compensation
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 11-Aug-2023