J/A+A/635/A131 12CO/13CO ratio in 126 nearby galaxy centers (Israel, 2020)
Central molecular zones in galaxies:
12CO-to-13CO ratios, carbon budget, and X factors
Israel F.P.
<Astron. Astrophys. 635, A131 (2020)>
=2020A&A...635A.131I 2020A&A...635A.131I (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Carbon monoxide ; Abundances
Keywords: galaxies: general - galaxies: abundances - galaxies: ISM -
galaxies: statistics - galaxies: starburst - ISM: molecules
Abstract:
We present ground-based measurements of 126 nearby galaxy centers in
12CO and 92 in 13CO in various low-J transitions. More than 60
galaxies were measured in at least four lines. The average relative
intensities of the first four J 12CO transitions are
1.00:0.92:0.70:0.57. In the first three J transitions, the
average 12CO-to-13CO intensity ratios are 13.0, 11.6, and 12.8,
with individual values in any transition ranging from 5 to 25. The
sizes of central CO concentrations are well defined in maps, but
poorly determined by multi-aperture photometry. On average, the J=1-0
12CO fluxes increase linearly with the size of the observing beam.
CO emission covers only a quarter of the HI galaxy disks. Using
radiative transfer models (RADEX), we derived model gas parameters.
The assumed carbon elemental abundances and carbon gas depletion onto
dust are the main causes of uncertainty. The new CO data and published
[CI] and [CII] data imply that CO, C, and C+ each represent about
one-third of the gas-phase carbon in the molecular interstellar
medium. The mean beam-averaged molecular hydrogen column density is
N(H2)=(1.5±0.2)1021cm-2. Galaxy center CO-to- H2 conversion
factors are typically ten times lower than the 'standard' Milky
Way X disk value, with a mean X(CO)=(1.9±0.2)1019cm-2/(K.km/s)
and a dispersion 1.7. The corresponding [CI]-H2 factor is five times
higher than X(CO), with X[CI]=(9±2)1019cm-2/(K.km/s). No unique
conversion factor can be determined for [CII]. The low molecular gas
content of galaxy centers relative to their CO intensities is
explained in roughly equal parts by high central gas-phase carbon
abundances, elevated gas temperatures, and large gas velocity
dispersions relative to the corresponding values in galaxy disks.
Description:
We determined intensities of galaxy centers in the lowest J
transitions of 12CO and 13CO for a total of 126 galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 36 126 Galaxy sample
table2.dat 37 113 Galaxy center J=1-0 line intensities
table3.dat 48 103 Galaxy center J=2-1 line intensities
table4.dat 31 88 Galaxy center J=3-2 line intensities
table5.dat 28 24 Galaxy center J=4-3 line intensities
table6.dat 41 79 Spatial distribution of CO emission
table7.dat 58 74 Line intensity ratios normalized to 22" aperture
table8.dat 10 18 Galaxies with J=1-0 isotopologue ratio only
table9.dat 29 69 Physical properties of 22" central regions
tablea1.dat 37 735 J=1-0 fluxes in different beams
refs.dat 104 82 References
tableb1.dat 85 50 Detailed comparison of J=1-0 12CO/13CO
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
7 A1 --- n_Name [*] * for Seyfert galaxies (1)
8- 12 F5.1 Mpc Dist Corrected distances from the NASA/IPAC
Extragalactic Database (NED) (2)
14- 19 F6.2 [W/m2] logFIR ? IRAS FIR flux
21- 25 F5.2 [Lsun] logLFIR ? FIR luminosity from Dist and logFIR
27- 31 F5.2 arcmin D25a Optical size (3)
32 A1 --- --- [x]
33- 36 F4.1 arcmin D25b ? Optical size (3)
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Note (1): * for Seyfert galaxies (Huchra & Burg 1992ApJ...393...90H 1992ApJ...393...90H;
Maiolino & Rieke, 1995ApJ...454...95M 1995ApJ...454...95M)
Note (2): Virgo+Great Attractor+Shapley Super-cluster case, assuming
H0=73.0km/s.
Note (3): taken from the Second Reference Catalog of Bright Galaxies
(2RCBG, de Vaucouleurs et al., 1976)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
7- 11 F5.1 K.km/s Int12COS45 ? 12CO J-1-0 line intensity,
SEST 45" beam
12 A1 --- n_Int12COS45 Note on Int12COS45 (1)
15- 20 F6.1 K.km/s Int12COS122 ? 12CO J-1-0 line intensity,
IRAM 122" beam
21 A1 --- n_Int12COS122 Note on Int12COS122 (1)
25- 29 F5.2 K.km/s Int13COS47 ? 13CO J-1-0 line intensity,
SEST 47" beam
33- 37 F5.2 K.km/s Int13COS122 ? 13CO J-1-0 line intensity,
IRAM 122" beam
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Note (1): Note as follows:
a = IRAM, Albrecht et al. (2007A&A...462..575A 2007A&A...462..575A)
b = SEST, Elfhag et al.(1996, Cat. J/A+AS/115/439)
c = IRAM, Braine et al.(1993A&AS...97..887B 1993A&AS...97..887B)
d = SEST, Chini et al. (1996, Cat. J/A+AS/118/47)
e = SEST, Aalto et al. (1995A&A...300..369A 1995A&A...300..369A)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
8- 14 F7.2 K.km/s Int12COJ45 ? J=2-1 12CO line intensity, JCMT 45" beam
15 A1 --- n_Int12COJ45 Note on Int12COJ45 (1)
16- 21 F6.1 K.km/s Int12COJ22 ? J=2-1 12CO line intensity, JCMT 22" beam
22 A1 --- n_Int12COJ22 Note on Int12COJ22 (1)
26- 31 F6.1 K.km/s Int12COI11 ? J=2-1 12CO line intensity, IRAM 11" beam
34 A1 --- l_Int13COJ23 Limit flag on Int13COJ23
35- 40 F6.2 K.km/s Int13COJ23 ? J=2-1 13CO line intensity, JCMT 23" beam
42 A1 --- l_Int13COI11 Limit flag on Int13COI11
43- 48 F6.2 K.km/s Int13COI11 ? J=2-1 13CO line intensity, IRAM 11" beam
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Note (1): Notes as follows:
a = SEST, This Paper
b = SEST, Ott et al. (2001A&A...372..463O 2001A&A...372..463O)
c = SEST, Aalto et al. (1995A&A...300..369A 1995A&A...300..369A)
d = SEST, Chini et al. (1996, Cat. J/A+AS/118/47)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
8- 14 F7.2 K.km/s Int12COJ22 ? J=3-2 12CO line intensity, JCMT 22" beam
17- 23 F7.2 K.km/s Int12COJ14 ? J=3-2 12CO line intensity, JCMT 14" beam
25 A1 --- l_Int13COJ14 Limit flag on Int13COJ14
26- 31 F6.2 K.km/s Int13COJ14 ? J=3-2 13CO line intensity, JCMT 14" beam
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
8- 12 F5.1 K.km/s Int12COJ22 ? J=4-3 12CO line intensity, JCMT 22" beam
15- 20 F6.1 K.km/s Int12COJ14 ? J=4-3 12CO line intensity, JCMT 14" beam
23- 28 F6.1 K.km/s Int12COJ11 ? J=4-3 12CO line intensity, JCMT 11" beam
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
9- 11 F3.1 --- alphaWG ? Whole galaxy alpha slope (defined by
F∝thetaalpha) describing the
increase of flux F with beam-width theta
14- 16 F3.1 arcmin dCOWG ? Whole galaxy CO extend in arcmin, equals the
angular size at which the extrapolated CO
flux reaches the total CO flux taken from the
literature
19- 21 I3 % dCOWGp ? Whole galaxy CO distance, as a fraction of
the optical galaxy size D25
25- 28 F4.1 10-9sr OMEGACOCp ? Central peak solid angle, OMEGACO
30- 32 A3 --- n_OMEGACOCp Note on OMEGACOCp
33- 37 A5 --- rOMEGACOCp Reference(s) for OMEGACOCp (1)
39- 41 F3.1 kpc RCOcp ? Central peak FWHM radius, RCO
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Note (1): References as follows:
1 = Rampazzo et al. (2006MNRAS.368..851R 2006MNRAS.368..851R)
2 = Yun & Hibbard (2001ApJ...550..104Y 2001ApJ...550..104Y)
3 = Gerin et al. (1988A&A...203...44G 1988A&A...203...44G)
4 = Sandquist (1999A&A...343..367S 1999A&A...343..367S)
6 = Seaquist & Clark (2001ApJ...552..133S 2001ApJ...552..133S)
7 = Kuno et al. (2000PASJ...52..775K 2000PASJ...52..775K)
8 = Garcia-Burillo et al. (2000A&A...363..869G 2000A&A...363..869G)
9 = Wilson et al. (2000ApJ...542..120W 2000ApJ...542..120W); Zhu et al. (2003ApJ...588..243Z 2003ApJ...588..243Z);
Schulz et al. (2007A&A...466..467S 2007A&A...466..467S)
10 = Kuno et al. (2007PASJ...59..117K 2007PASJ...59..117K)
11 = Sofue et al. (2003PASJ...55...75S 2003PASJ...55...75S)
12 = Cox & Downes (1996ApJ...473..219C 1996ApJ...473..219C)
13 = Shibatsuka et al. (2003PASJ...55...87S 2003PASJ...55...87S)
14 = Ott et al. (2001A&A...372..463O 2001A&A...372..463O)
15 = Helfer et al. (2003ApJS..145..259H 2003ApJS..145..259H)
16 = Regan et al. (1999ApJ...526...97R 1999ApJ...526...97R)
17 = Eckart et al. (1991ApJ...372...67E 1991ApJ...372...67E)
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
7 A1 --- n_Name Note on Name (1)
11- 15 F5.1 --- f22 ? Fraction of all CO flux contained in
an aperture of 22"
18- 21 F4.2 --- TR1 ? Transition ratio, 12CO(2-1)=1, J=1-0
24- 27 F4.2 --- TR2 ? Transition ratio, 12CO(2-1)=1, J=3-2
30- 34 F5.2 --- TR3 ? Transition ratio, 12CO(2-1)=1, J=4-3
39- 42 F4.1 --- IR1 ? Isotopologue ratio, 12CO/13CO, J=1-0
43- 45 A3 --- n_IR1 Note on IR1 (1)
47- 50 F4.1 --- IR2 ? Isotopologue ratio, 12CO/13CO, J=2-1
52 A1 --- n_IR2 Note on IR2 (1)
55- 58 F4.1 --- IR3 ? Isotopologue ratio, 12CO/13CO, J=3-2
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Note (1): References as follows:
1 = Cox & Downes (1996ApJ...473..219C 1996ApJ...473..219C)
2 = Krips et al. (2010MNRAS.407.2261K 2010MNRAS.407.2261K)
3 = Dahlem et al. (1993A&A...270...29D 1993A&A...270...29D)
4 = Hitschfeld et al. (2008A&A...479...75H 2008A&A...479...75H)
5 = Vila-Vilaro et al. (2015ApJS..218...28V 2015ApJS..218...28V)
6 = Aalto et al. (1995A&A...300..369A 1995A&A...300..369A)
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
7- 10 F4.1 --- I12CO/I13CO Isotopologue ratio 12CO/13CO J=1-0
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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- 5 A5 --- Name Galaxy name
9- 10 I2 % [CO]/[C] Adopted beam-averaged fractional CO abundance
12- 14 I3 10+17cm-2 NC Gas-phase total carbon column density (1)
16- 19 F4.1 10+21cm-2 NH2 ? Beam-averaged molecular hydrogen
column density
21- 24 F4.1 10+7Msun Mgas ? Total gas mass (2)
26- 29 F4.2 --- X Hydrogen abundance, in X0 unit
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Note (1): NH=2000NC for the adopted gas-phase carbon abundance (Appendix C).
Note (2): Mgas=1.35MH allowing for the presence of helium
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Name Galaxy name
8- 12 A5 --- Tel Telescope (or ave) (1)
14- 17 F4.1 arcsec Beam ? Beam
19- 21 A3 --- n_Beam [tot All] tot for extrapolated to galaxy size,
All for All
22 A1 --- l_Flux Limti flag on flux
23- 28 I6 Jy.km/s Flux Measured flux
30- 34 I5 Jy.km/s e_Flux ? rms uncertainty on Flux
36- 37 A2 --- Ref Reference, in refs.dat
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Note (1): Telescope as follows:
BTL = Bell Telephone Labs
SEST = Swedish-ESO Submillimeter Telescope
OSO = Onsala Space Observatory
IRAM = Institut Radio Astronomie Millimetrique - Pico Veleta
NOB = Nobeyama
FCRAO = Five Colleges Radio Observatory
NRAO = National Radio Astronomy Observatory
PMO = Purple Mountain Observatory
CSO = Caltech Submillimeter Observatory
SMA = Smithsonian Millimeter Array
OVRO = Owens Valley Radio Observatory
BIMA = Berkeley Illinois Maryland Array
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Galaxy name
7- 10 F4.1 --- TP Newly determined isotopologue ratio
J=1-0 12CO/13CO, resolution 22"
13- 16 F4.1 --- BTL ? BLT 100" beam-width isotopologue ratio
J=1-0 12CO/13CO
18- 21 F4.1 --- NRAO ? NRAO 55" beam-width isotopologue ratio
J=1-0 12CO/13CO
22 A1 --- --- [/]
23- 26 F4.1 --- NRAO2 ? Second NRAO 55" beam-width isotopologue
ratio J=1-0 12CO/13CO
29- 32 F4.1 --- AROKP ? AROKP 55" beam-width isotopologue ratio
J=1-0 12CO/13CO
34- 37 F4.1 --- FCRAO ? FCRAO 45" beam-width isotopologue ratio
J=1-0 12CO/13CO
38 A1 --- --- [/]
39- 42 F4.1 --- FCRAO2 ? Second FCRAO 45" beam-width isotopologue
ratio J=1-0 12CO/13CO
44- 47 F4.1 --- PMO ? PMO 45" beam-width isotopologue ratio
J=1-0 12CO/13CO
48 A1 --- l_SEST Limit flag on SEST
49- 52 F4.1 --- SEST ? SEST 45" beam-width isotopologue ratio
J=1-0 12CO/13CO
53 A1 --- --- [/]
54- 55 I2 --- SEST2 ? Second SEST 45" beam-width isotopologue
ratio J=1-0 12CO/13CO
57- 60 F4.1 --- OSO ? OSO 33" beam-width isotopologue ratio
J=1-0 12CO/13CO
62- 65 F4.1 --- IRAM ? IRAM 22" beam-width isotopologue ratio
J=1-0 12CO/13CO
66 A1 --- --- [/]
67- 70 F4.1 --- IRAM2 ? Second IRAM 22" beam-width isotopologue
ratio J=1-0 12CO/13CO
72- 85 A14 --- Refs References (1)
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Note (1): References as follows:
1 = Papadopoulos et al. (2012MNRAS.426.2601P 2012MNRAS.426.2601P, Cat. J/MNRAS/426/2601)
2 = Tan et al. (2011RAA....11..787T 2011RAA....11..787T)
4 = Paglione et al. (2001ApJS..135..183P 2001ApJS..135..183P)
5 = Papadopoulos et al. (1998ApJ...492..521P 1998ApJ...492..521P)
6 = Aalto et al. (1995A&A...300..369A 1995A&A...300..369A)
7 = Garay et al. (1993A&A...277..405G 1993A&A...277..405G)
8 = Casoli et al. (1992A&A...264...49C 1992A&A...264...49C)
10 = Aalto et al. (1991A&A...247..291A 1991A&A...247..291A)
11 = Young & Sanders (1986ApJ...302..680Y 1986ApJ...302..680Y)
12 = Rickard & Blitz (1985ApJ...292L..57R 1985ApJ...292L..57R)
13 = Encrenaz et al. (1979A&A....78L...1E 1979A&A....78L...1E)
16 = Schulz et al. (2007A&A...466..467S 2007A&A...466..467S)
18 = Braine, Combes & van Driel (1993A&A...280..451B 1993A&A...280..451B)
19 = Golla & Wielebinsky (1994A&A...286..733G 1994A&A...286..733G)
20 = Eckart et al. (1991ApJ...372...67E 1991ApJ...372...67E)
23 = Sandqvist et al. (1988A&A...201..223S 1988A&A...201..223S)
25 = Mao et al. (2000A&A...358..433M 2000A&A...358..433M)
26 = Costagliola et al. (2011A&A...528A..30C 2011A&A...528A..30C)
28 = Vila-Vilaro et al. (2015ApJS..218...28V 2015ApJS..218...28V)
29 = Krips et al. (2010MNRAS.407.2261K 2010MNRAS.407.2261K)
31 = Cormier et al. (2018MNRAS.475.3909C 2018MNRAS.475.3909C)
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference code
4- 22 A19 --- Bibcode BibCode
24- 54 A31 --- Aut Author's name
56-104 A49 --- Com Comments
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History:
Frank Israel,
(End) Patricia Vannier [CDS] 27-Feb-2020