J/A+A/578/A53 Spectroscopy of Herschel Dwarf Galaxy Survey (Cormier+, 2015)
The Herschel Dwarf Galaxy Survey:
I. Properties of the low-metallicity ISM from PACS spectroscopy.
Cormier D., Madden S. C., Lebouteiller V., Abel N., Hony S., Galliano F.,
Remy-Ruyer A., Bigiel F., Baes M., Boselli A., Chevance M., Cooray A.,
De Looze I., Doublier V., Galametz M., Hugues T., Karczewski O.L.,
Lee M.-Y., Lu N., Spinoglio L.
<Astron. Astrophys. 578, A53 (2015)>
=2015A&A...578A..53C 2015A&A...578A..53C
ADC_Keywords: Galaxies, IR ; Interstellar medium ; Spectroscopy
Keywords: galaxies: dwarf - infrared: ISM -
photon-dominated regions (PDR) - techniques: spectroscopic -
radiative transfer - HII regions
Abstract:
We present Herschel PACS spectroscopic observations of the [CII]
157um, [OI] 63 and 145um, [OIII] 88um, [NII] 122 and 205um, and [NIII]
57um fine-structure cooling lines in a sample of 48 low-metallicity
star-forming galaxies of the guaranteed time key program Dwarf Galaxy
Survey. We correlate PACS line ratios and line-to-LTIR ratios with
LTIR, LTIR/LB, metallicity, and FIR color, and interpret the observed
trends in terms of ISM conditions and phase filling factors with
Cloudy radiative transfer models. We find that the ISM of
low-metallicity dwarf galaxies has a more porous structure than that
of metal-rich galaxies. The radiation fields are harder and the the
ionized gas/PDR filling factor is larger in the dwarfs.
Description:
Far-infrared line fluxes from the Herschel PACS instrument are
provided for the 48 galaxies of the Dwarf Galaxy Survey. An atlas of
images also shows spectral maps and line profiles for all sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4a.dat 167 43 Far-IR line fluxes of the compact sample
table4b.dat 158 12 Far-IR line peak surface brightnesses of the
extended sample
list.dat 26 55 Description of atlas of the PACS spectroscopy
observations from the Herschel Dwarf Galaxy
Survey content
dgs_atlas.pdf 512 87187 *Spectral maps and line profiles
tablea1.dat 114 231 Technical details about the DGS observations
tablec1.dat 182 29 Low-resolution MIR line fluxes in the compact
galaxies of the DGS
tablec2.dat 163 22 High-resolution MIR line fluxes in the compact
galaxies of the DGS
tabled1a.dat 35 43 Total IR luminosity of the compact sample
tabled1b.dat 35 55 Total IR luminosity of the extended sample
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Note on dgs_atlas.pdf: It contains all the PACS spectroscopic maps of the
Herschel Dwarf Galaxy Survey. For each galaxy, we present the flux map of
each observed line on the left hand side, and the rebinned spectrum of the
brightest spatial pixel on the right hand side. The position of this spectrum
is indicated by a dark cross on the map. White circles represent the
PACS beam sizes.
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Byte-by-byte Description of file: table4a.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Galaxy name (1)
13- 14 I2 h RAh Right Ascension (J2000)
16- 17 I2 min RAm Right Ascension (J2000)
19- 22 F4.1 s RAs Right Ascension (J2000)
24 A1 --- DE- Declination sign (J2000)
25- 26 I2 deg DEd Declination (J2000)
28- 29 I2 arcmin DEm Declination (J2000)
31- 32 I2 arcsec DEs Declination (J2000)
34 A1 --- l_F157 3σ upper limit flag on F157
35- 42 F8.2 aW/m2 F157 ? [CII] 157µm emission line flux
43- 50 F8.2 aW/m2 e_F157 ? rms uncertainty on F157
52 A1 --- l_F063 3σ upper limit flag on F063
53- 60 F8.2 aW/m2 F063 ? [OI] 63µm emission line flux
61- 68 F8.2 aW/m2 e_F063 ? rms uncertainty on F063
70 A1 --- l_F088 3σ upper limit flag on F088
71- 78 F8.2 aW/m2 F088 ? [OIII] 88µm emission line flux
79- 86 F8.2 aW/m2 e_F088 ? rms uncertainty on F088
88 A1 --- l_F145 3σ upper limit flag on F145
89- 96 F8.2 aW/m2 F145 ? [OI] 145µm emission line flux
97-104 F8.2 aW/m2 e_F145 ? rms uncertainty on F145
106 A1 --- l_F122 3σ upper limit flag on F122
107-114 F8.2 aW/m2 F122 ? [NII] 122µm emission line flux
115-122 F8.2 aW/m2 e_F122 ? rms uncertainty on F122
124 A1 --- l_F205 3σ upper limit flag on F205
125-132 F8.2 aW/m2 F205 ? [NII] 205µm emission line flux
133-140 F8.2 aW/m2 e_F205 ? rms uncertainty on F205
142 A1 --- l_F057 3σ upper limit flag on F057
143-150 F8.2 aW/m2 F057 ? [NIII] 57µm emission line flux
151-158 F8.2 aW/m2 e_F057 ? rms uncertainty on F057
160-167 F8.2 --- corr [0.15/0.6]? Dust correction factor (2)
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Note (1): Sources belonging to the compact sample of this paper.
Note (2): Fraction of the dust emission at 100um outside the PACS line coverage.
Correction to apply to recover the total line flux. For NGC1140, this factor
needs not to be applied for [CII] because its spatial coverage is larger.
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Byte-by-byte Description of file: table4b.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Galaxy name (1)
13- 14 I2 h RAh Right Ascension (J2000)
16- 17 I2 min RAm Right Ascension (J2000)
19- 22 F4.1 s RAs Right Ascension (J2000)
24 A1 --- DE- Declination sign (J2000)
25- 26 I2 deg DEd Declination (J2000)
28- 29 I2 arcmin DEm Declination (J2000)
31- 32 I2 arcsec DEs Declination (J2000)
34 A1 --- l_F157 3σ upper limit flag on F157
35- 42 F8.1 nW/m2/sr F157 ? [CII] 157µm emission surface brightness
43- 50 F8.1 nW/m2/sr e_F157 ? rms uncertainty on F157
52 A1 --- l_F063 3σ upper limit flag on F063
53- 60 F8.1 nW/m2/sr F063 ? [OI] 63µm emission surface brightness
61- 68 F8.1 nW/m2/sr e_F063 ? rms uncertainty on F063
70 A1 --- l_F088 3σ upper limit flag on F088
71- 78 F8.1 nW/m2/sr F088 ? [OIII] 88µm emission surface brightness
79- 86 F8.1 nW/m2/sr e_F088 ? rms uncertainty on F088
88 A1 --- l_F145 3σ upper limit flag on F145
89- 96 F8.1 nW/m2/sr F145 ? [OI] 145µm emission surface brightness
97-104 F8.1 nW/m2/sr e_F145 ? rms uncertainty on F145
106 A1 --- l_F122 3σ upper limit flag on F122
107-114 F8.1 nW/m2/sr F122 ? [NII] 122µm emission surface brightness
115-122 F8.1 nW/m2/sr e_F122 ? rms uncertainty on F122
124 A1 --- l_F205 3σ upper limit flag on F205
125-132 F8.1 nW/m2/sr F205 ? [NII] 205µm emission surface brightness
133-140 F8.1 nW/m2/sr e_F205 ? rms uncertainty on F205
142 A1 --- l_F057 3σ upper limit flag on F057
143-150 F8.1 nW/m2/sr F057 ? [NIII] 57µm emission surface brightness
151-158 F8.1 nW/m2/sr e_F057 ? rms uncertainty on F057
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Note (1): Sources partially mapped and considered extended in this paper. For
those sources, peak surface brightnesses in 10-9W/m2/sr are given.
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Galaxy name
13- 14 I2 --- Page [2/25] Page number in dgs_atlas.pdf file
16- 26 A11 --- FileName Name of the table with Far-IR data
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name
14- 15 I2 h RAh Map center right ascension (J2000)
17- 18 I2 min RAm Map center right ascension (J2000)
20- 24 F5.2 s RAs Map center right ascension (J2000)
26 A1 --- DE- Map center declination sign (J2000)
27- 28 I2 deg DEd Map center declination (J2000)
30- 31 I2 arcmin DEm Map center declination (J2000)
33- 36 F4.1 arcsec DEs Map center declination (J2000)
38- 47 I10 --- OBSID Observation Identification number
49- 50 A2 --- Mode Observing mode (1)
52- 54 I3 --- Nx [47/191] Map size along X-axis
55 A1 --- --- [x]
56- 58 I3 --- Ny [47/215] Map size along Y-axis
60-114 A55 --- Line Observed lines
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Note (1): Observing mode as follows:
UN = Unchopped Line Scan
CN = Chopnod Line Scan
WS = Wavelength Switching
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name
13- 14 A2 --- l_F10.5 [≤ ] Limit flag on F10.5 (2σ)
15- 21 F7.2 aW/m2 F10.5 ?=- [SIV] 10.5um line flux
23- 27 F5.2 aW/m2 e_F10.5 ? rms uncertainty on F10.5
29- 30 A2 --- l_F12.8 [≤ ] Limit flag on F12.8 (2σ)
31- 37 F7.2 aW/m2 F12.8 ?=- [NeII] 12.8um line flux
39- 44 F6.2 aW/m2 e_F12.8 ? rms uncertainty on F12.8
46- 47 A2 --- l_F15.6 [≤ ] Limit flag on F15.6 (2σ)
48- 54 F7.2 aW/m2 F15.6 ?=- [NeIII] 15.6um line flux
56- 61 F6.2 aW/m2 e_F15.6 ? rms uncertainty on F15.6
63- 64 A2 --- l_F18.7 [≤ ] Limit flag on F18.7 (2σ)
65- 71 F7.2 aW/m2 F18.7 ?=- [SIII] 18.7um line flux
73- 78 F6.2 aW/m2 e_F18.7 ? rms uncertainty on F18.7
80- 81 A2 --- l_F33.5 [≤ ] Limit flag on F33.5 (2σ)
82- 88 F7.2 aW/m2 F33.5 ?=- [SIII] 33.5um line flux
90- 95 F6.2 aW/m2 e_F33.5 ? rms uncertainty on F33.5
97-100 F4.2 --- R24 [0.8/3.2]?=- Observed to synthetic MIPS 24µm
flux ratio
102-105 F4.2 --- e_R24 ? rms uncertainty on R24
107-108 A2 --- l_F6.99 [≤ ] Limit flag on F6.99 (2σ)
109-114 F6.2 aW/m2 F6.99 ?=- [ArII] 6.99um line flux
116-120 F5.2 aW/m2 e_F6.99 ? rms uncertainty on F6.99
122-123 A2 --- l_F14.3 [≤ ] Limit flag on F14.3 (2σ)
124-129 F6.2 aW/m2 F14.3 ?=- [NeV] 14.3um line flux
131-135 F5.2 aW/m2 e_F14.3 ? rms uncertainty on F14.3
137-138 A2 --- l_F25.9 [≤ ] Limit flag on F25.9 (2σ)
139-144 F6.2 aW/m2 F25.9 ?=- [OIV] 25.9um line flux
146-150 F5.2 aW/m2 e_F25.9 ? rms uncertainty on F25.9
152-153 A2 --- l_F34.8 [≤ ] Limit flag on F34.8 (2σ)
154-160 F7.2 aW/m2 F34.8 ?=- [SiII] 34.8um line flux
162-167 F6.2 aW/m2 e_F34.8 ? rms uncertainty on F34.8
169-170 A2 --- l_F36.0 [≤ ] Limit flag on F36.0 (2σ)
171-177 F7.2 aW/m2 F36.0 ?=- [NeIII] 36.0um line flux
179-182 F4.2 aW/m2 e_F36.0 ? rms uncertainty on F36.0
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name
12 A1 --- n_Name [*] Point-like source (1)
14- 15 A2 --- l_F10.5 [≤ ] Limit flag on F10.5 (2σ)
16- 22 F7.2 aW/m2 F10.5 ?=- [SIV] 10.5um line flux
24- 29 F6.2 aW/m2 e_F10.5 ? rms uncertainty on F10.5
31- 32 A2 --- l_F12.8 [≤ ] Limit flag on F12.8 (2σ)
33- 39 F7.2 aW/m2 F12.8 ?=- [NeII] 12.8um line flux
41- 46 F6.2 aW/m2 e_F12.8 ? rms uncertainty on F12.8
48- 49 A2 --- l_F15.6 [≤ ] Limit flag on F15.6 (2σ)
50- 56 F7.2 aW/m2 F15.6 ?=- [NeIII] 15.6um line flux
58- 63 F6.2 aW/m2 e_F15.6 ? rms uncertainty on F15.6
65- 66 A2 --- l_F18.7 [≤ ] Limit flag on F18.7 (2σ)
67- 73 F7.2 aW/m2 F18.7 ?=- [SIII] 18.7um line flux
75- 80 F6.2 aW/m2 e_F18.7 ? rms uncertainty on F18.7
82- 83 A2 --- l_F33.5 [≤ ] Limit flag on F33.5 (2σ)
84- 90 F7.2 aW/m2 F33.5 ?=- [SIII] 33.5um line flux
92- 97 F6.2 aW/m2 e_F33.5 ? rms uncertainty on F33.5
99-102 F4.2 --- HR/LR ?=- Ratio between High-to-low dispersion fluxes
104-105 A2 --- l_F14.3 [≤ ] Limit flag on F14.3 (2σ)
106-112 F7.2 aW/m2 F14.3 ?=- [NeV] 14.3um line flux
114-115 A2 --- l_F25.9 [≤ ] Limit flag on F25.9 (2σ)
116-122 F7.2 aW/m2 F25.9 ?=- [OIV] 25.9um line flux
124-129 F6.2 aW/m2 e_F25.9 ? rms uncertainty on F25.9
131-132 A2 --- l_F34.8 [≤ ] Limit flag on F34.8 (2σ)
133-139 F7.2 aW/m2 F34.8 ?=- [SiII] 34.8um line flux
141-146 F6.2 aW/m2 e_F34.8 ? rms uncertainty on F34.8
148-149 A2 --- l_F36.0 [≤ ] Limit flag on F36.0 (2σ)
150-156 F7.2 aW/m2 F36.0 ?=- [NeIII] 36.0um line flux
158-163 F6.2 aW/m2 e_F36.0 ? rms uncertainty on F36.0
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Note (1): * indicates point-like sources reduced with the optimal extraction
method. The other sources are extracted from the full apertures. We note that
the observation of Pox 186 (AOR key 9007360) is not included because it is
not centered on the source.
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Byte-by-byte Description of file: tabled1a.dat
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Bytes Format Units Label Explanations
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1 A1 --- Sample [C] Compact
3- 13 A11 --- Name Source name
17- 20 F4.2 --- 60/100 ?=- IRAS flux ratio F60/F100
21 A1 --- n_60/100 [*] * for synthetic IRAS fluxes
23- 26 F4.2 --- 70/100 ?=- PACS fluxes ratio F70/F100
28- 35 E8.3 Lsun LTIR ?=- Total IR (3-1100µm) luminosity;
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Byte-by-byte Description of file: tabled1b.dat
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Bytes Format Units Label Explanations
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1 A1 --- Sample [E] Extended sample
3- 13 A11 --- Name Source name
17- 20 F4.2 --- 60/100 ?=- IRAS flux ratio F60/F100
21 A1 --- n_60/100 [*] * for synthetic IRAS fluxes
23- 26 F4.2 --- 70/100 ?=- PACS fluxes ratio F70/F100
28- 35 E8.3 W/m2/sr LTIR ?=- Total IR (3-1100µm) surface brightness
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Acknowledgements:
Diane Cormier, diane.cormier(at)zah.uni-heidelberg.de
References:
Madden et al., An Overview of the Dwarf Galaxy Survey, 2013PASP..125..600M 2013PASP..125..600M
Remy-Ruyer et al., Revealing the cold dust in low-metallicity environments.
I. Photometry analysis of the Dwarf Galaxy Survey with Herschel,
2013A&A...557A..95R 2013A&A...557A..95R
History:
* 03-Jun-2015: First on-line version
* 25-Sep-2015: tables A1, C1, C2 and D1 added (from electronic version)
(End) Patricia Vannier [CDS] 17-Feb-2015