J/ApJ/862/110 Metallicity measurements in 70 nearby galaxies (Schruba+, 2018)
The metallicity dependence of the H I shielding layers in nearby galaxies.
Schruba A., Bialy S., Sternberg A.
<Astrophys. J., 862, 110 (2018)>
=2018ApJ...862..110S 2018ApJ...862..110S
ADC_Keywords: Galaxies, nearby; Abundances; Interstellar medium
Keywords: galaxies: ISM ; ISM: atoms ; ISM: molecules ; radio lines: galaxies
Abstract:
We investigate the metallicity dependence of HI surface densities in
star-forming regions along many lines of sight within 70 nearby
galaxies, probing kiloparsec to 50pc scales. We employ HI, SFR,
stellar mass, and metallicity (gradient) measurements from the
literature, spanning a wide range (5dex) in stellar and gas mass and
(1.6dex) in metallicity. We consider metallicities as observed, or
rescaled to match the mass-metallicity relation determined for SDSS
galaxies. At intermediate to high metallicities (0.3-2 times solar),
we find that the HI surface densities saturate at sufficiently large
total gas surface density. The maximal HI columns vary approximately
inversely with metallicity, and show little variation with spatial
resolution, galactocentric radius, or among galaxies. In the central
parts of massive spiral galaxies, the HI gas is depressed by factors
of ∼2. The observed behavior is naturally reproduced by metallicity
dependent shielding theories for the HI-to-H2 transitions in
star-forming galaxies. We show that the inverse scaling of the maximal
HI columns with metallicity suggests that the area filling fraction of
atomic-molecular complexes in galaxies is of the order of unity, and
weakly dependent on metallicity.
Description:
For our study, we compile HI and SFR surface density maps, using 21cm
observations (Section 2.1) and FUV and 24µm photometry (Section 2.2).
Table 1 lists additional parameters with their literature references.
The HI data are taken from the VLA surveys THINGS (Walter+ 2008,
J/AJ/136/2563), LITTLE THINGS (Hunter+ 2012, J/AJ/144/134), VLA-ANGST
(Ott+ 2012AJ....144..123O 2012AJ....144..123O), and a recent extension of THINGS for
spiral galaxies also surveyed by Herschel (NGC 2798, 3049, 3190, 3938,
4236, 4321, 4536, 4594, 4625, 4725, 5474; to be presented by Leroy,
Sandstrom, Schruba et al.). The angular resolution is between 5.8 and
24.8 arcsec with a median of 11.7 arcsec.
We derive SFRs from the combination of GALEX FUV (1350-1750Å) and
Spitzer 24um maps.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 68 70 Sample properties
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See also:
J/A+A/448/955 : Abundances of emission galaxies in SDSS-DR3 (Izotov+, 2006)
J/ApJS/173/185 : GALEX UV atlas of nearby galaxies (Gil de Paz+, 2007)
J/AJ/136/2782 : Star formation efficiency in nearby galaxies (Leroy+, 2008)
J/AJ/136/2563 : HI Nearby Galaxy Survey, THINGS (Walter+, 2008)
J/ApJ/703/517 : The Spitzer Local Volume Legacy: IR photometry (Dale+, 2009)
J/AJ/140/1194 : FUV/HI relations in nearby galaxies (Bigiel+, 2010)
J/ApJ/715/506 : Aromatic inventory of the local volume (Marble+, 2010)
J/ApJS/190/233 : Spectroscopy & abund. of SINGS galaxies (Moustakas+, 2010)
J/MNRAS/415/32 : COLD GASS survey (Saintonge+, 2011)
J/AJ/143/133 : Dwarf galaxies from the ALFALFA survey (Huang+, 2012)
J/AJ/144/134 : LITTLE THINGS survey of nearby dwarf galaxies (Hunter+, 2012)
J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)
J/A+A/539/A143 : Nearby B-stars stellar parameters and abund. (Nieva+, 2012)
J/ApJ/745/173 : UV absorption sight lines of LMC and SMC (Welty+, 2012)
J/ApJ/765/140 : Stacked spectra of SDSS star forming gal. (Andrews+, 2013)
J/MNRAS/445/899 : LVL SEDs and physical properties (Cook+, 2014)
J/AJ/147/131 : Abundances of nearby late-type galaxies. I. (Pilyugin+, 2014)
J/A+A/582/A121 : Dust properties in galaxies (Remy-Ruyer+, 2015)
J/ApJ/830/4 : HII region abundances in NGC 5457 (M101) (Croxall+, 2016)
J/A+A/590/A27 : CO spectra of Virgo cluster galaxies (Grossi,+, 2016)
J/A+A/595/A62 : CALIFA galaxies O/H and N/O slopes (Perez-Montero+, 2016)
J/ApJ/824/29 : ATLASGAL clumps with IRAS & MALT90 data (Stephens+, 2016)
J/ApJ/835/278 : Molecular clouds in the dwarf galaxy NGC6822 (Schruba+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Galaxy name
10- 13 F4.1 Mpc Dist [0.7/19.2] Distance
15- 18 A4 --- r_Dist Reference for distance (1)
20- 24 F5.2 [Msun] Mstar [6.5/11.2]? log10 stellar mass
26- 29 A4 --- r_Mstar Reference for stellar mass (1)
31- 34 F4.2 [-] Metal [7.3/8.7] Metallicity measurement
(12+log(O/H))
36- 39 F4.2 [-] e_Metal [0.01/0.3] Uncertainty in metallicity
41- 41 A1 --- f_Metal Type of metallicity (2)
43- 46 A4 --- r_Metal Reference for metallicity (1)
48- 51 F4.2 [-] Del(O/H) [0/0.3] Metallicity rescaling value (3)
53- 57 F5.2 --- Grad [-0.9/0.05]? Metallicity gradient
(in units of dex/R25)
59- 63 F5.2 --- e_Grad [0/0.5]? Uncertainty in metallicity gradient
65- 68 A4 --- r_Grad ? Reference for metallicity gradient (1)
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Note (1): References as follows:
A17 = Annibali et al. (2017ApJ...843...20A 2017ApJ...843...20A);
B12 = Berg et al. (2012ApJ...754...98B 2012ApJ...754...98B);
C09 = Croxall et al. (2009ApJ...705..723C 2009ApJ...705..723C);
C14 = Cook et al. (2014, J/MNRAS/445/899);
C16 = Croxall et al. (2016, J/ApJ/830/4);
D06 = Davidge (2006ApJ...641..822D 2006ApJ...641..822D);
E08 = Engelbracht et al. (2008ApJ...678..804E 2008ApJ...678..804E);
H12 = Hunter et al. (2012, J/AJ/144/134);
J12 = Johnson et al. (2012AJ....144..152J 2012AJ....144..152J);
K11 = Kennicutt et al. (2011PASP..123.1347K 2011PASP..123.1347K);
MA10 = Marble et al. (2010, J/ApJ/715/506);
MC12 = McConnachie (2012, J/AJ/144/4);
MM15 = Munoz-Mateos et al. (2015ApJS..219....3M 2015ApJS..219....3M);
MO10 = Moustakas et al. (2010, J/ApJS/190/233);
MQ17 = McQuinn et al. (2017AJ....154...51M 2017AJ....154...51M);
O12 = Ott et al. (2012AJ....144..123O 2012AJ....144..123O);
P14 = Pilyugin et al. (2014, J/AJ/147/131);
P15 = Pilyugin et al. (2015MNRAS.450.3254P 2015MNRAS.450.3254P);
P16 = Pilyugin & Grebel (2016MNRAS.457.3678P 2016MNRAS.457.3678P);
RR14 = Remy-Ruyer et al. (2014A&A...563A..31R 2014A&A...563A..31R);
RR15 = Remy-Ruyer et al. (2015, J/A+A/582/A121);
S18 = This paper;
W08 = Walter et al. (2008, J/AJ/136/2563)
Note (2): Metallicity methods as follows:
d = direct electron temperature;
m = mix;
s = strong line.
Note (3): Difference between observed metallicities and mass-metallicity
relationship by Andrews & Martini (2013, J/ApJ/765/140). Here only
applied for strong line metallicities.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 30-Jul-2019