J/ApJ/880/127 EMPIRE: IRAM 30m dense gas survey (Jimenez-Donaire+, 2019)
EMPIRE: the IRAM 30m dense gas survey of nearby galaxies.
Jimenez-Donaire M.J., Bigiel F., Leroy A.K., Usero A., Cormier D.,
Puschnig J., Gallagher M., Kepley A., Bolatto A., Garcia-Burillo S.,
Hughes A., Kramer C., Pety J., Schinnerer E., Schruba A., Schuster K.,
Walter F.
<Astrophys. J., 880, 127 (2019)>
=2019ApJ...880..127J 2019ApJ...880..127J
ADC_Keywords: Galaxies, nearby; Interstellar medium; Radio lines; Molecular data
Keywords: galaxies: ISM ; galaxies: star formation ; ISM: molecules ;
radio lines: galaxies
Abstract:
We present EMPIRE, an IRAM 30m large program that mapped
λ=3-4mm dense gas tracers at ∼1-2kpc resolution across the
whole star-forming disk of nine nearby massive spiral galaxies. We
describe the EMPIRE observing and reduction strategies and show new
whole-galaxy maps of HCN(1-0), HCO+(1-0), HNC(1-0), and CO(1-0). We
explore how the HCN-to-CO and IR-to-HCN ratios, observational proxies
for the dense gas fraction and dense gas star formation efficiency,
depend on host galaxy and local environment. We find that the fraction
of dense gas correlates with stellar surface density, gas surface
density, molecular-to-atomic gas ratio, and dynamical equilibrium
pressure. In EMPIRE, the star formation rate per unit dense gas is
anticorrelated with these same environmental parameters. Thus,
although dense gas appears abundant in the central regions of many
spiral galaxies, this gas appears relatively inefficient at forming
stars. These results qualitatively agree with previous work on nearby
galaxies and the Milky Way's Central Molecular Zone. To first order,
EMPIRE demonstrates that the conditions in a galaxy disk set the gas
density distribution and that the dense gas traced by HCN shows an
environment-dependent relation to star formation. However, our results
also show significant (±0.2dex) galaxy-to-galaxy variations. We
suggest that gas structure below the scale of our observations and
dynamical effects likely also play an important role.
Description:
Table 1 lists the 9 EMIR Multiline Probe of the ISM Regulating Galaxy
Evolution (EMPIRE; PI: F. Bigiel) targets. All targets are nearby
(d≤15Mpc) face-on (i≤65°) spiral galaxies that are also large on
the sky (≥2').
The observations for EMPIRE were carried out at the IRAM 30m telescope
located at Pico Veleta, Spain. Most of the data were taken from 2014
December through 2016 December for ∼440h over the course of 16 runs.
We used the 3mm band (E090) of the dual-polarization EMIR receiver,
which yields an instantaneous bandwidth of 15.6GHz per polarization.
We tuned EMIR with a local oscillator frequency of ∼98.6GHz. This
allowed us to simultaneously observe the bright high critical density
tracers HCN(1-0), HCO+(1-0), and HNC(1-0) and the optically thin
molecular column tracers 13CO(1-0) and C18O(1-0).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 75 9 EMPIRE galaxy sample
table9.dat 81 2118 Individual line-of-sight measurements
table10.dat 78 58 Individual radial profiles
table11.dat 37 540 Dense gas literature compilation
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See also:
VII/237 : HYPERLEDA. I. Catalog of galaxies (Paturel+, 2003)
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/ApJ/706/599 : Hα and UV SFR in the local volume (Lee+, 2009)
J/ApJ/723/1019 : Galactic SFR and gas surface densities (Heiderman+, 2010)
J/ApJS/190/233 : Spectroscopy & abundances of SINGS gal. (Moustakas+, 2010)
J/PASP/122/1397 : Spitzer Survey of Stellar Structure in Gal. (Sheth+, 2010)
J/A+A/549/A17 : IRAM spectra toward M33 Giant Mol. Clouds (Buchbender+, 2013)
J/AJ/146/150 : Velocity dispersions of 12 nearby gal. (Caldu-Primo+, 2013)
J/ApJ/805/31 : IR-radio luminosities & surface densities (Liu+, 2015)
J/ApJ/824/29 : ATLASGAL clumps with IRAS & MALT90 data (Stephens+, 2016)
J/ApJ/831/73 : MCs associated with HII reg. (Vutisalchavakul+, 2016)
J/ApJ/846/71 : M51 ISM structures from the CO maps of PAWS (Leroy+, 2017)
J/ApJ/835/217 : Density distributions for mm-wave line ratios (Leroy+, 2017)
J/ApJ/858/90 : Radial profiles of 5 nearby galaxies (Gallagher+, 2018)
J/A+A/610/A77 : Orion Integral Filament N2H+(1-0) data (Hacar+, 2018)
J/ApJ/860/172 : Cloud-scale molecular gas properties in 15 gal. (Sun+, 2018)
J/A+A/625/A19 : 33GHz continuum map of M51 (Querejeta+, 2019)
http://empiresurvey.webstarts.com/ : The EMPIRE survey of dense gas home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [NGC]
5- 8 I4 --- NGC NGC number
10- 11 I2 h RAh Hour of right ascension (J2000)
13- 14 I2 min RAm Minute of right ascension (J2000)
16- 19 F4.1 s RAs Second of right ascension (J2000)
21 A1 --- DE- Sign of declination (J2000)
22- 23 I2 deg DEd Degree of declination (J2000)
25- 26 I2 arcmin DEm Arcminute of declination (J2000)
28- 29 I2 arcsec DEs Arcsecond of declination (J2000)
31- 32 I2 --- inc [7/65] Inclination from HyperLeda
34- 36 I3 deg PA [20/243] Position angle from HyperLeda
38- 40 F3.1 --- r25 [2.5/5.9] Radius of the B-band 25th magnitude
isophote from HyperLeda
42- 45 F4.1 pc Dist [7/16.8] Distance from the Extragalactic
Distance Database (Tully+ 2009AJ....138..323T 2009AJ....138..323T)
47- 52 F6.1 km/s Vhel [42.4/2407] Heliocentric central velocity
from Walter+ (2008, J/AJ/136/2563)
54- 57 F4.2 --- Metal [8.34/8.68] Metallicity 12+log(O/H) (1)
59- 63 A5 --- Morph Morphological type from NED
65- 70 E6.2 --- SFR [0.0028/0.021] Average SFR surface density
inside 0.75 r25
from Leroy+ (2013AJ....146...19L 2013AJ....146...19L)
72- 75 F4.1 [Msun] logM [10/10.6] Log of integrated stellar mass
of the entire galaxy based on 3.6um emission
from Dale+ (2007ApJ...655..863D 2007ApJ...655..863D and
2009, J/ApJ/703/517)
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Note (1): Globally averaged metallicities are taken from
Moustakas+ (2010, J/ApJS/190/233), except for NGC 2903
(Engelbracht+ 2008ApJ...678..804E 2008ApJ...678..804E).
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [ngc]
4- 7 I4 --- NGC [628/6946] NGC number of the galaxy
9- 12 F4.2 --- R25 [0/1.1] Galactocentric radius normalized to r25
14 A1 --- l_IHCN Upper limit flag (2)
15- 18 F4.2 K.km/s IHCN [0.1/6.5]? HCN(1-0) integrated intensity (1)
20- 23 F4.2 K.km/s e_IHCN [0.04/0.2]? Uncertainty in IHCN
25 A1 --- l_IHCO+ Upper limit flag (2)
26- 29 F4.2 K.km/s IHCO+ [0.1/5.7]? HCO+(1-0) integrated intensity (1)
31- 34 F4.2 K.km/s e_IHCO+ [0.04/0.2]? Uncertainty in IHCO+
36 A1 --- l_IHNC Upper limit flag (2)
37- 40 F4.2 K.km/s IHNC [0.14/2.1]? HNC(1-0) integrated intensity (1)
42- 45 F4.2 K.km/s e_IHNC [0.07/0.5]? Uncertainty in IHNC
47 A1 --- l_I12CO Upper limit flag (2)
48- 53 F6.2 K.km/s I12CO [0.4/153]? 12CO(1-0) integrated intensity (1)
55- 58 F4.2 K.km/s e_I12CO [0.1/0.8]? Uncertainty in I12CO
60 A1 --- l_I13CO Upper limit flag (2)
61- 65 F5.2 K.km/s I13CO [0.14/10.1]? 13CO(1-0) integrated intensity (1)
67- 70 F4.2 K.km/s e_I13CO [0.04/0.4]? Uncertainty in I13CO
72 A1 --- l_IC18O Upper limit flag (2)
73- 76 F4.2 K.km/s IC18O [0/2.7]? C18O(1-0) integrated intensity (1)
78- 81 F4.2 K.km/s e_IC18O [0/0.2]? Uncertainty in IC18O
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Note (1): The data were sampled at a common angular resolution of 33".
Note (2): Where intensity measurements are below the significance
threshold (3σ RMS), the integrated intensities are upper limits.
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [ngc]
4- 7 I4 --- NGC NGC number of the galaxy
9- 13 F5.2 kpc Rad [0.58/10.4] Outer edge of stacking radius
15 A1 --- l_IHCN Upper limit flag (1)
16- 19 F4.2 K.km/s IHCN [0.01/3.3]? HCN(1-0) integrated intensity
21- 24 F4.2 K.km/s e_IHCN [0.01/0.09]? Uncertainty in IHCN
26 A1 --- l_IHCO+ Upper limit flag (1)
27- 30 F4.2 K.km/s IHCO+ [0.01/2.9]? HCO+(1-0) integrated intensity
32- 35 F4.2 K.km/s e_IHCO+ [0/0.07]? Uncertainty in IHCO+
37 A1 --- l_IHNC Upper limit flag (1)
38- 41 F4.2 K.km/s IHNC [0/1.1]? HNC(1-0) integrated intensity
43- 46 F4.2 K.km/s e_IHNC [0/0.06]? Uncertainty in IHNC
48- 52 F5.2 K.km/s I12CO [1/86.3] 12CO(1-0) integrated intensity
54- 57 F4.2 K.km/s e_I12CO [0.05/1.8] Uncertainty in I12CO
59- 62 F4.2 K.km/s I13CO [0.07/5.6]? 13CO(1-0) integrated intensity
64- 67 F4.2 K.km/s e_I13CO [0.02/0.3]? Uncertainty in I13CO
69 A1 --- l_IC18O Upper limit flag (1)
70- 73 F4.2 K.km/s IC18O [0.01/1.4]? C18O(1-0) integrated intensity
75- 78 F4.2 K.km/s e_IC18O [0.03/0.1]? Uncertainty in IC18O
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Note (1): Where intensity measurements are below the significance
threshold (3σ RMS), the integrated intensities are upper limits.
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Byte-by-byte Description of file: table11.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Ref Reference identifier (1)
18- 25 F8.5 [Lsun] logLIR [1.95/13.75] log IR luminosity
27- 35 F9.6 [K.km/s/pc2] logLHCN [-1.11/10.67]? log HCN(1-0) luminosity
37 A1 --- OT Type code (2)
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Note (1): Reference as follows:
Bigiel15 = 2015ApJ...815..103B 2015ApJ...815..103B
Braine16 = 2017A&A...597A..44B 2017A&A...597A..44B
Brouillet05 = 2005A&A...429..153B 2005A&A...429..153B
Buchbender13 = 2013A&A...549A..17B 2013A&A...549A..17B
Chen17 = 2017ApJ...836..101C 2017ApJ...836..101C
Chin97 = 1997A&A...317..548C 1997A&A...317..548C
Chin98 = 1998A&A...303..901C 1998A&A...303..901C
Crocker = 2012MNRAS.421.1298C 2012MNRAS.421.1298C
Gallagher18 = 2018ApJ...858...90G 2018ApJ...858...90G
Gao04 = 2004ApJ...606..271G 2004ApJ...606..271G
Gao07 = 2007ApJ...660L.271G 2007ApJ...660L.271G
Garcia-Burillo12 = 2012A&A...539A...8G 2012A&A...539A...8G
Gracia-Carpio08 = 2008A&A...479..703G 2008A&A...479..703G
Juneau09 = 2009ApJ...707.1217J 2009ApJ...707.1217J
Kepley14 = 2014ApJ...780L..13K 2014ApJ...780L..13K
Krips08 = 2008ApJ...677..262K 2008ApJ...677..262K
Privon15 = 2015ApJ...814...39P 2015ApJ...814...39P
Stephens16 = 2016ApJ...824...29S 2016ApJ...824...29S
Usero15 = 2015AJ....150..115U 2015AJ....150..115U
Wu10 = 2010ApJS..188..313W 2010ApJS..188..313W
Note (2): Type code as follows:
R = Resolved galaxy (77 occurrences);
I = Individual cloud or Core (254 occurrences).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-Jan-2021