J/A+A/644/A10 LARS XI. Turbulence Driven Lyman Alpha Escape (Puschnig+, 2020)
The Lyman Alpha Reference Sample. XI: Efficient turbulence-driven Lyα
escape and the analysis of IR, CO and [C II]158um.
Puschnig J., Hayes M., Oestlin G., Cannon J., Smirnova-Pinchukova I.,
Husemann B., Kunth D., Bridge J., Herenz E.C., Messa M., Oteo I.
<Astron. Astrophys. 644, A10 (2020)>
=2020A&A...644A..10P 2020A&A...644A..10P (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, spectra ; Spectra, millimetric/submm - Spectra, infrared
Keywords: galaxies: evolution - galaxies: starburst - galaxies: irregular -
galaxies: ISM - infrared: galaxies - radio lines: galaxies
Abstract:
We study the global dust and (molecular) gas content in the Lyman
Alpha Reference Sample (LARS), i.e. 14 local star-forming galaxies. We
characterize their interstellar medium and relate newly derived
properties to quantities relevant for Lyα escape. We observed
LARS galaxies with Herschel/PACS, SOFIA/FIFI-LS, the IRAM 30m
telescope and APEX, targeting far-infrared (FIR) continuum and
emission lines of [CII]158um, [OI]63um, [OIII]88um and low-J CO lines.
Using Bayesian methods we derive dust model parameters and estimate
total gas masses for all LARS galaxies, taking into account a
metallicity-dependent gas-to-dust ratio. Star formation rates were
estimated from FIR, [CII]158um and [OI]63um luminosities. LARS covers
a wide dynamic range in the derived properties, with FIR-based star
formation rates from ∼0.5-100M_☉/yr, gas fractions between ∼15-80%
and gas depletion times ranging from a few hundred Myr up to more than
10Gyr. The distribution of LARS galaxies in the {SIGMA}gas vs.
{SIGMA}SFR (Kennicutt-Schmidt plane) is thus quite heterogeneous.
However, we find that LARS galaxies with the longest gas depletion
times, i.e. relatively high gas surface densities ({SIGMA}gas)
and low star formation rate densities ({SIGMA}SFR have by far the
highest Lyα escape fraction. A strong [Math Processing
Error]linear relation is found between Lyα escape fraction and
the total gas (HI+H2) depletion time. We argue that the Lyα
escape in those galaxies is driven by turbulence in the star-forming
gas that shifts the Lyα photons out of resonance close to the
places where they originate. We further report on an extreme
[CII]158um excess in LARS 5, corresponding to ∼14±3% of the FIR
luminosity, i.e. the most extreme [CII]-to-FIR ratio observed in a
non-AGN galaxy to date.
Description:
We observed LARS (Lyman Alpha Reference Sample) galaxies with
Herschel/PACS, SOFIA/FIFI-LS, the IRAM 30m telescope and
APEX,targeting far-infrared (FIR) continuum and emission lines of
[CII]158um, [OI]63um, [OIII]88um and low-J CO lines. This catalogue
contains the fully reduced spectra.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sources.dat 124 14 List of studied sources
list.dat 142 22 List of fits spectra
fits/* . 22 Individual fits spectra
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Byte-by-byte Description of file: sources.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Name Source name
10- 11 I2 h RAh Right ascension (J2000)
13- 14 I2 min RAm Right ascension (J2000)
16- 19 F4.1 s RAs Right ascension (J2000)
21 A1 --- DE- Declination sign (J2000)
22- 23 I2 deg DEd Declination (J2000)
25- 26 I2 arcmin DEm Declination (J2000)
28- 31 F4.1 arcsec DEs Declination (J2000)
33- 49 A17 --- CO1-0 Name of the fits spectrum for CO(1-0) line
in subdirectory fits
51- 67 A17 --- CO2-1 Name of the fits spectrum for CO(2-1) line
in subdirectory fits
69- 85 A17 --- CO3-2 Name of the fits spectrum for CO(3-2) line
in subdirectory fits
87-104 A18 --- HCN1-0 Name of the fits spectrum for HCN(1-0) line
in subdirectory fits
106-124 A19 --- HCO+1-0 Name of the fits spectrum for HCO+(1-0) line
in subdirectory fits
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Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 22 I3 --- Nx Number of pixels along X-axis
24- 46 A23 "datime" Obs.date Observation date
48- 58 E11.6 Hz bFreq Lower value of frequency interval
60- 70 E11.6 Hz BFreq Upper value of frequency interval
72- 82 E11.6 Hz dFreq Frequency resolution
84 I1 Kibyte size Size of FITS file
86-104 A19 --- FileName Name of FITS file, in subdirectory fits
106-142 A37 --- Title Title of the FITS file
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Acknowledgements:
Johannes Puschnig, johannes.puschnig(at)uni-bonn.de
References:
Hayes et al. Paper I. 2013ApJ...765L..27H 2013ApJ...765L..27H
Hayes et al. Paper II. 2014ApJ...782....6H 2014ApJ...782....6H
Pardy et al. Paper III. 2014ApJ...794..101P 2014ApJ...794..101P
Guaita et al. Paper IV. 2015A&A...576A..51G 2015A&A...576A..51G
Rivera-Thorsen et al. Paper V. 2015ApJ...805...14R 2015ApJ...805...14R
Duval et al. Paper VI. 2016A&A...587A..77D 2016A&A...587A..77D
Herenz et al. Paper VII. 2016A&A...587A..78H 2016A&A...587A..78H
Bridge et al. Paper VIII. 2018ApJ...852....9B 2018ApJ...852....9B
Micheva et al. Paper IX. 2018A&A...615A..46M 2018A&A...615A..46M
Runnholm et al. Paper X. 2020ApJ...892...48R 2020ApJ...892...48R
Rasekh et al. Paper XII. 2022A&A...662A..64R 2022A&A...662A..64R
Melinder et al. Paper XIV. 2023ApJS..266...15M 2023ApJS..266...15M Cat. J/ApJS/266/15
(End) Patricia Vannier [CDS] 18-Nov-2020