J/A+A/626/A23 Herschel Dwarf Galaxy Survey PACS spectroscopy (Cormier+, 2019)
The Herschel Dwarf Galaxy Survey:
II. Physical conditions, origin of [CII] emission, and porosity of the
multiphase low-metallicity ISM.
Cormier D., Abel N. P., Hony S., Lebouteiller V., Madden S. C.,
Polles F.L., Galliano F., De Looze I., Galametz M., Lambert-Huyghe A.
<Astron. Astrophys. 626, A23 (2019)>
=2019A&A...626A..23C 2019A&A...626A..23C (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, IR ; Interstellar medium ; Spectroscopy ; Models
Keywords: radiative transfer - HII regions - photon-dominated regions -
galaxies: dwarf - galaxies: ISM - infrared: ISM
Abstract:
We employ a multiphase approach to model the ISM phases of the
galaxies from the Herschel Dwarf Galaxy Survey with the spectral
synthesis code Cloudy. We characterize the physical conditions (gas
densities, radiation fields, porosity) in those galaxies and
investigate correlations with metallicity or star-formation activity.
We find that the lower-metallicity galaxies tend to have higher
ionization parameters and galaxies with higher specific star-formation
rates have higher gas densities. The [CII] emission arises mainly from
PDRs and the contribution from the ionized gas phases is small,
typically less than 30% of the observed emission. We also find a
correlation, with scatter, between metallicity and both the PDR
covering factor and the fraction of [CII] from the ionized gas.
Overall, the low metal abundances appear to be driving most of the
changes in the ISM structure and conditions of these galaxies, and not
the high specific star-formation rates. These results demonstrate in a
quantitative way the increase of ISM porosity at low metallicity.
Description:
We provide fluxes of the mid-infrared and far-infrared lines studied
in this paper for the galaxies of the Dwarf Galaxy Survey observed
with the Spitzer and Herschel telescopes. Line intensities predicted
by our grid of models are also provided.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
obs.dat 460 42 Observed MIR and FIR line fluxes
model1.dat 291 280 *Predicted MIR and FIR line fluxes at AV=5mag
model2.dat 291 280 *Predicted MIR and FIR line fluxes at the
ionization front
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Note on model1.dat: All luminosities are emergent with models stopping
at AV=5 mag. All models have input luminosity of 109 solar luminosities.
Note on model2.dat: Luminosities are extracted at the ionization front in the
grid of models. All models have input luminosity of 109 solar luminosities.
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See also:
J/A+A/582/A121 : Dust properties in galaxies (Remy-Ruyer+, 2015)
J/A+A/578/A53 : Spectroscopy of Herschel Dwarf Galaxy Survey (Cormier+, 2015)
Byte-by-byte Description of file: obs.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Galaxy name
14- 20 F7.3 10-16W/m2 OIII88 ?=- Flux of [OIII] 88 micron emission line
24- 28 F5.3 10-16W/m2 e_OIII88 ?=- Uncertainty on OIII88 (1)
30- 36 F7.3 10-16W/m2 NIII57 ?=- Flux of [NIII] 57 micron emission line
40- 44 F5.3 10-16W/m2 e_NIII57 ?=- Uncertainty on NIII57 (1)
46- 52 F7.3 10-16W/m2 NII122 ?=- Flux of [NII] 122 micron emission line
55 A1 --- l_NII122 [-] - for 1-sigma upper limit
56- 60 F5.3 10-16W/m2 e_NII122 ?=- Uncertainty on NII122 (1)
62- 68 F7.3 10-16W/m2 NeIII15 ?=- Flux of [NeIII] 15.6 micron emission line
70 A1 --- l_NeIII15 [-] - for 1-sigma upper limit
71- 76 F6.3 10-16W/m2 e_NeIII15 ?=- Uncertainty on NeIII15 (1)
78- 84 F7.3 10-16W/m2 NeII12 ?=- Flux of [NeII] 12.8 micron emission line
87 A1 --- l_NeII12 [-] - for 1-sigma upper limit
88- 92 F5.3 10-16W/m2 e_NeII12 ?=- Uncertainty on NeII12 (1)
94-100 F7.3 10-16W/m2 SIV10 ?=- Flux of [SIV] 10.5 micron emission line
103-108 F6.3 10-16W/m2 e_SIV10 ?=- Uncertainty on SIV10 (1)
110-116 F7.3 10-16W/m2 SIII18 ?=- Flux of [SIII] 18.7 micron emission line
118 A1 --- l_SIII18 [-] - for 1-sigma upper limit
119-124 F6.3 10-16W/m2 e_SIII18 ?=- Uncertainty on SIII18 (1)
126-132 F7.3 10-16W/m2 SIII33 ?=- Flux of [SIII] 33.5 micron emission line
134 A1 --- l_SIII33 [-] - for 1-sigma upper limit
135-140 F6.3 10-16W/m2 e_SIII33 ?=- Uncertainty on SIII33 (1)
142-148 F7.3 10-16W/m2 CII157 Flux of [CII] 157 micron emission line
151 A1 --- l_CII157 [-] - for 1-sigma upper limit
152-156 F5.3 10-16W/m2 e_CII157 Uncertainty on CII157 (1)
158-164 F7.3 10-16W/m2 SiII34 ?=- Flux of [SiII] 34.8 micron emission line
166 A1 --- l_SiII34 [-] - for 1-sigma upper limit
167-172 F6.3 10-16W/m2 e_SiII34 ?=- Uncertainty on SiII34 (1)
174-180 F7.3 10-16W/m2 OIV26 ?=- Flux of [OIV] 25.9 micron emission line
183 A1 --- l_OIV26 [-] - for 1-sigma upper limit
184-188 F5.3 10-16W/m2 e_OIV26 ?=- Uncertainty on OIV26 (1)
190-196 F7.3 10-16W/m2 ArII7 ?=- Flux of [ArII] 6.99 micron emission line
199 A1 --- l_ArII7 [-] - for 1-sigma upper limit
200-204 F5.3 10-16W/m2 e_ArII7 ?=- Uncertainty on ArII7 (1)
206-212 F7.3 10-16W/m2 ArIII9 ?=- Flux of [ArIII] 8.99 micron emission line
215 A1 --- l_ArIII9 [-] - for 1-sigma upper limit
216-220 F5.3 10-16W/m2 e_ArIII9 ?=- Uncertainty on ArIII9 (1)
222-228 F7.3 10-16W/m2 FeII17 ?=- Flux of [FeII] 17.9 micron emission line
231 A1 --- l_FeII17 [-] - for 1-sigma upper limit
232-236 F5.3 10-16W/m2 e_FeII17 ?=- Uncertainty on FeII17 (1)
238-244 F7.3 10-16W/m2 FeII25 ?=- Flux of [FeII] 26.0 micron emission line
247 A1 --- l_FeII25 [-] - for 1-sigma upper limit
248-252 F5.3 10-16W/m2 e_FeII25 ?=- Uncertainty on FeII25 (1)
254-260 F7.3 10-16W/m2 FeIII23 ?=- Flux of [FeIII] 22.9 micron emission line
263 A1 --- l_FeIII23 [-] - for 1-sigma upper limit
264-268 F5.3 10-16W/m2 e_FeIII23 ?=- Uncertainty on FeIII23 (1)
270-276 F7.3 10-16W/m2 ArIII21 ?=- Flux of [ArIII] 21.8 micron emission line
279 A1 --- l_ArIII21 [-] - for 1-sigma upper limit
280-284 F5.3 10-16W/m2 e_ArIII21 ?=- Uncertainty on ArIII21 (1)
286-292 F7.3 10-16W/m2 Hua12 ?=- Flux of HI Hua 12.4 micron emission line
295 A1 --- l_Hua12 [-] - for 1-sigma upper limit
296-300 F5.3 10-16W/m2 e_Hua12 ?=- Uncertainty on Hua12 (1)
302-308 F7.3 10-16W/m2 NII205 ?=- Flux of [NII] 205 micron emission line
312-316 F5.3 10-16W/m2 e_NII205 ?=- Uncertainty on NII205 (1)
318-324 F7.3 10-16W/m2 OI63 ?=- Flux of [OI] 63 micron emission line
327 A1 --- l_OI63 [-] - for 1-sigma upper limit
328-332 F5.3 10-16W/m2 e_OI63 ?=- Uncertainty on OI63 (1)
334-340 F7.3 10-16W/m2 OI145 ?=- Flux of [OI] 145 micron emission line
343 A1 --- l_OI145 [-] - for 1-sigma upper limit
344-348 F5.3 10-16W/m2 e_OI145 ?=- Uncertainty on OI145 (1)
350-356 F7.3 10-16W/m2 H2S0 ?=- Flux of H2 S(0) 28.2 micron emission line
359 A1 --- l_H2S0 [-] - for 1-sigma upper limit
360-364 F5.3 10-16W/m2 e_H2S0 ?=- Uncertainty on H2S0 (1)
366-372 F7.3 10-16W/m2 H2S1 ?=- Flux of H2 S(1) 17.0 micron emission line
375 A1 --- l_H2S1 [-] - for 1-sigma upper limit
376-380 F5.3 10-16W/m2 e_H2S1 ?=- Uncertainty on H2S1 (1)
382-388 F7.3 10-16W/m2 H2S2 ?=- Flux of H2 S(2) 12.3 micron emission line
391 A1 --- l_H2S2 [-] - for 1-sigma upper limit
392-396 F5.3 10-16W/m2 e_H2S2 ?=- Uncertainty on H2S2 (1)
398-404 F7.3 10-16W/m2 H2S3 ?=- Flux of H2 S(3) 9.66 micron emission line
407 A1 --- l_H2S3 [-] - for 1-sigma upper limit
408-412 F5.3 10-16W/m2 e_H2S3 ?=- Uncertainty on H2S3 (1)
414-420 F7.3 10-16W/m2 NeV14 ?=- Flux of [NeV] 14.3 micron emission line
423 A1 --- l_NeV14 [-] - for 1-sigma upper limit
424-428 F5.3 10-16W/m2 e_NeV14 ?=- Uncertainty on NeV14 (1)
430-436 F7.3 10-16W/m2 NeV24 ?=- Flux of [NeV] 24.2 micron emission line
439 A1 --- l_NeV24 [-] - for 1-sigma upper limit
440-444 F5.3 10-16W/m2 e_NeV24 ?=- Uncertainty on NeV24 (1)
446-452 F7.3 10-14W/m2 LTIR ?=- Total infrared flux (3-1000 micron)
454 A1 --- l_LTIR [-] - for 1-sigma upper limit
455-460 F6.3 10-14W/m2 e_LTIR ?=- Uncertainty on LTIR (1)
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Note (1): Uncertainties on the fluxes do not include calibration or abundance
uncertainties.
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Byte-by-byte Description of file: model1.dat model2.dat
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Bytes Format Units Label Explanations
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1- 5 F5.2 --- Zbin Metallicity bin
6- 10 F5.2 [cm-3] lognH Density
11- 16 F6.2 [cm] logrin Inner radius
17- 22 F6.2 [-] logU Ionization parameter
23- 27 F5.2 --- logG0 PDR radiation field, scaling factor to the
Habing radiation field
29- 35 F7.3 [Lsun] logArII7 Luminosity of [ArII] 6.99 micron
emission line
37- 43 F7.3 [Lsun] logArIII9 Luminosity of [ArIII] 8.99 micron
emission line
45- 51 F7.3 [Lsun] logSIV10 Luminosity of [SIV] 10.5 micron
emission line
53- 59 F7.3 [Lsun] logHua12 Luminosity of HI Hua 12.4 micron
emission line
61- 67 F7.3 [Lsun] logNeII12 Luminosity of [NeII] 12.8 micron
emission line
69- 75 F7.3 [Lsun] logNeIII15 Luminosity of [NeIII] 15.6 micron
emission line
77- 83 F7.3 [Lsun] logFeII17 Luminosity of [FeII] 17.9 micron
emission line
85- 91 F7.3 [Lsun] logSIII18 Luminosity of [SIII] 18.7 micron
emission line
93- 99 F7.3 [Lsun] logArIII21 Luminosity of [ArIII] 21.8 micron
emission line
101-107 F7.3 [Lsun] logFeIII23 Luminosity of [FeIII] 22.9 micron
emission line
109-115 F7.3 [Lsun] logFeII25 Luminosity of [FeII] 26.0 micron
emission line
117-123 F7.3 [Lsun] logSIII33 Luminosity of [SIII] 33.5 micron
emission line
125-131 F7.3 [Lsun] logNeIII36 Luminosity of [NeIII] 36.0 micron
emission line
133-139 F7.3 [Lsun] logOIII52 Luminosity of [OIII] 52 micron emission line
141-147 F7.3 [Lsun] logNIII57 Luminosity of [NIII] 57 micron emission line
149-155 F7.3 [Lsun] logOIII88 Luminosity of [OIII] 88 micron emission line
157-163 F7.3 [Lsun] logNII122 Luminosity of [NII] 122 micron emission line
165-171 F7.3 [Lsun] logNII205 Luminosity of [NII] 205 micron emission line
173-179 F7.3 [Lsun] logSiII34 Luminosity of [SiII] 34.8 micron
emission line
181-187 F7.3 [Lsun] logOI63 Luminosity of [OI] 63 micron emission line
189-195 F7.3 [Lsun] logOI145 Luminosity of [OI] 145 micron emission line
197-203 F7.3 [Lsun] logCII157 Luminosity of [CII] 157 micron emission line
205-211 F7.3 [Lsun] logH2S0 ? Luminosity of H2 S(0) 28.2 micron
emission line
212 A1 --- n_logH2S0 [I] I for -Infinity
213-219 F7.3 [Lsun] logH2S1 ? Luminosity of H2 S(1) 17.0 micron
emission line
220 A1 --- n_logH2S1 [I] I for -Infinity
221-227 F7.3 [Lsun] logH2S2 ? Luminosity of H2 S(2) 12.3 micron
emission line
228 A1 --- n_logH2S2 [I] I for -Infinity
229-235 F7.3 [Lsun] logH2S3 ? Luminosity of H2 s(3) 9.66 micron
emission line
236 A1 --- n_logH2S3 [I] I for -Infinity
237-243 F7.3 [Lsun] logCO1-0 ? Luminosity of CO(1-0) 115GHz emission line
244 A1 --- n_logCO1-0 [I] I for -Infinity
245-251 F7.3 [Lsun] logCO2-1 ? Luminosity of CO(2-1) 230GHz emission line
252 A1 --- n_logCO2-1 [I] I for -Infinity
253-259 F7.3 [Lsun] logCO3-2 ? Luminosity of CO(3-2) 345GHz emission line
260 A1 --- n_logCO3-2 [I] I for -Infinity
261-267 F7.3 [Lsun] logCI370 Luminosity of [CI] 370 micron emission line
269-275 F7.3 [Lsun] logCI610 Luminosity of [CI] 610 micron emission line
277-283 F7.3 [-] logfCII Fraction of [CII]157 in the ionized gas
285-291 F7.3 [-] logfSiII Fraction of [SiII]34 in the ionized gas
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Acknowledgements:
Diane Cormier, diane.cormier(at)cea.fr
References:
Madden et al., 2013PASP..125..600M 2013PASP..125..600M, An overview of the Dwarf Galaxy Survey
(End) Patricia Vannier [CDS] 10-Apr-2019