J/ApJ/809/146 SDSS-DR8 isolated low-mass galaxies (Bradford+, 2015)
A study in blue: the baryon content of isolated low-mass galaxies.
Bradford J.D., Geha M.C., Blanton M.R.
<Astrophys. J., 809, 146 (2015)>
=2015ApJ...809..146B 2015ApJ...809..146B (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, spectra ; H I data ; Interstellar medium ; Stars, masses
Keywords: galaxies: dwarf; galaxies: evolution; galaxies: ISM;
galaxies: kinematics and dynamics
Abstract:
We study the baryon content of low-mass galaxies selected from the
Sloan Digital Sky Survey (SDSS DR8), focusing on galaxies in isolated
environments where the complicating physics of galaxy-galaxy
interactions are minimized. We measure neutral hydrogen (HI) gas
masses and line widths for 148 isolated galaxies with stellar mass
between 107 and 109.5M☉. We compare isolated low-mass
galaxies to more massive galaxies and galaxies in denser environments
by remeasuring HI emission lines from the Arecibo Legacy Fast ALFA
survey 40% data release. All isolated low-mass galaxies either have
large atomic gas fractions or large atomic gas fractions cannot be
ruled out via their upper limits. We measure a median atomic gas
fraction of fgas=0.81±0.13 for our isolated low-mass sample with
no systems below 0.30. At all stellar masses, the correlations between
galaxy radius, baryonic mass, and velocity width are not significantly
affected by environment. Finally, we estimate a median baryon to total
dynamical mass fraction of fbaryon,disk=0.15±0.17. We also
estimate two different median baryon to halo mass fractions using the
results of semi-analytic models (fbaryon,disk=0.04±0.06) and
abundance matching (fbaryon,halo=0.04±0.02). Baryon fractions
estimated directly using HI observations appear independent of
environment and maximum circular velocity, while baryon fractions
estimated using abundance matching show a significant depletion of
baryons at low maximum circular velocities.
Description:
To construct a sample of isolated low-mass galaxies, we begin with the
NASA Sloan Atlas (NSA) catalog (Blanton et al. 2011AJ....142...31B 2011AJ....142...31B),
which is itself a re-reduction of the SDSS Data Release 8 (DR8; Aihara
et al. 2011ApJS..193...29A 2011ApJS..193...29A). This sample was first described in (Geha
et al. 2012ApJ...757...85G 2012ApJ...757...85G).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 98 1715 Isolated galaxy data sample
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
VIII/77 : HI spectral properties of galaxies (Springob+, 2005)
VII/198 : Mark III Catalog of Galaxy Peculiar Velocities (Willick+ 1997)
J/ApJS/220/3 : SDSS-DR7 isolated galaxy morphologies (Khim+, 2015)
J/AJ/147/134 : Tully-Fisher relation for S4G galaxies (Zaritsky+, 2014)
J/A+A/564/A94 : CIG sample 3-D environment (Argudo-Fernandez+, 2014)
J/A+A/560/A9 : AMIGA. Isolation degree revision (Argudo-Fernandez+, 2013)
J/MNRAS/439/1015 : Velocities of red giants in LG dwarf galaxies (Kirby+, 2014)
J/MNRAS/436/34 : GALEX Arecibo SDSS survey. Final release (Catinella+, 2013)
J/ApJ/775/116 : z<0.06 active black hole gal. from SDSS-DR8 (Reines+, 2013)
J/MNRAS/434/325 : 452 AMIGA galaxies physical param. (Fernandez Lorenzo+ 2013)
J/MNRAS/425/2741 : Parameters of Spiral galaxies from SDSS 7 (Hall+, 2012)
J/AJ/144/16 : Optical & HI properties of gal. in voids (Kreckel+, 2012)
J/AJ/143/133 : Properties of dwarf galaxies from ALFALFA (Huang+, 2012)
J/AJ/142/170 : ALFALFA survey: the α.40 HI sources (Haynes+, 2011)
J/AJ/142/153 : Precision spectrophotometry at the level of 0.1% (Yan, 2011)
J/A+A/534/A102 : AMIGA IX. Molecular gas properties (Lisenfeld+, 2011)
J/MNRAS/415/32 : COLD GASS survey (Saintonge+, 2011)
J/ApJ/726/108 : Dispersion-supported stellar systems (Tollerud+, 2011)
J/MNRAS/403/683 : GALEX Arecibo SDSS survey (GASS) (Catinella+, 2010)
J/AJ/136/2782 : Star formation efficiency in nearby galaxies (Leroy+, 2008)
J/ApJ/653/1027 : TKRS/GOODS-N Field galaxies (Weiner+, 2006)
J/ApJ/653/240 : Low-mass SDSS dwarf galaxy properties (Geha+, 2006)
J/AJ/129/2062 : SDSS DR1 isolated galaxies (Allam+, 2005)
J/A+A/422/941 : Gas content in 1038 interacting galaxies (Casasola+, 2004)
J/AJ/128/16 : HIPASS Bright Galaxy Catalog (Koribalski+, 2004)
http://www.sdss3.org/ : SDSS-III home page
http://www.nsatlas.org/ : NASA-Sloan Atlas home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- NSA [162/171138] NASA Sloan Atlas v0.1.2
identifier
8- 9 I2 h RAh Hour of Right Ascension (J2000)
11- 12 I2 min RAm Minute of Right Ascension (J2000)
14- 18 F5.2 s RAs Second of Right Ascension (J2000)
20- 20 A1 --- DE- Sign of the Declination (J2000)
21- 22 I2 deg DEd Degree of Declination (J2000)
24- 25 I2 arcmin DEm Arcminute of Declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of Declination (J2000)
33- 38 F6.2 Mpc Dist [13/246] Heliocentric luminosity distance
40- 43 F4.2 Mpc e_Dist [1/4] Uncertainty in Dist
45- 46 I2 deg Inc [8/90] Inclination Angle
48- 51 I4 km/s W20i [18/1157] Inclination corrected velocity
width of 21-cm line at 20% peak flux
53- 55 I3 km/s e_W20i [0/357] Uncertainty in W20i
57- 61 F5.2 kpc Reff [0.2/29.1] Effective radius at assumed
distance
63- 66 F4.2 kpc e_Reff [0.01/0.6] Uncertainty in reff
68- 73 F6.3 10+9Msun MHI [0.01/59.1] HI Mass
75- 80 F6.3 10+9Msun e_MHI [0.004/28] Uncertainty in MHI
82- 88 F7.3 10+9Msun Mstar [0.007/262.3] Stellar mass
90- 96 F7.3 10+9Msun e_Mstar [0.003/121] Uncertainty in Mstar
98- 98 I1 --- Ref Source of HI observations (1)
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Note (1): Reference for primary source of HI observation as follows:
1 = this study,
2 = Haynes et al. (2011, J/AJ/142/170) ALFALFA survey
3 = Geha et al. (2006, J/ApJ/653/240)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Dec-2015