J/A+A/677/A15 GUAPOS III. O- and N-bearing complexes (Mininni+, 2023)
The GUAPOS project: III. Characterization of the O- and N-bearing complex
organic molecules content and search for chemical differentiation.
Mininni C., Beltran M.T., Colzi L., Rivilla V.M., Fontani F.,
Lorenzani A., Lopez-Gallifa A., Viti S., Sanchez-Monge A., Schilke P.,
Testi A.
<Astron. Astrophys. 677, A15 (2023)>
=2023A&A...677A..15M 2023A&A...677A..15M (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Radio lines
Keywords: astrochemistry - ISM: molecules - stars: formation -
ISM: individual objects: G31.41+0.31
Abstract:
The G31.41+0.31 Unbiased ALMA sPectral Observational Survey (GUAPOS)
project targets the hot molecular core (HMC) G31.41+0.31 (G31), to
unveil the complex chemistry of one of the most chemically rich
high-mass star-forming regions outside the Galactic Center (GC). In
the third paper of the project we present a study of nine O-bearing
(CH3OH, C13H3OH, CH3O18H, CH3CHO, CH3OCH3,
CH3COCH3, C2H5OH, aGg'-(CH2OH)2, and gGg'-(CH2OH)2)
and six N-bearing (CH3CN, C13H3CN, CH3C13N, C2H3CN,
C2H5CN, and C2H5C13N) complex organic molecules toward G31.
The aim of this work is to characterize the abundances in G31 and to
compare them with the values estimated in other sources. Moreover, we
search for a possible chemical segregation between O-bearing and
N-bearing species in G31, which hosts four compact sources as seen
with higher angular resolution data. In the discussion we also include
the three isomers of C2H4O2 and the O- and N-bearing molecular
species NH2CHO, CH3NCO, CH3C(O)CH2, and CH3NHCHO, analyzed
in previous GUAPOS papers. The observations were carried out with the
interferometer ALMA and cover the entire Band 3 from 84 to 116GHz
(∼32GHz bandwidth) with an angular resolution of 1.2"x1.2"
(∼4400aux4400au) and a spectral resolution of ∼0.488MHz
(∼1.3-1.7km/s). The transitions of the fourteen molecular species have
been analyzed with the tool SLIM of MADCUBA to determine the physical
parameters of the emitting gas. Moreover, we have analyzed the
morphology of the emission of the molecular species. The values of
abundances w.r.t H2 in G31 range from 10-6 to 10-10 for the
different species. We have compared the abundances w.r.t methanol of
O-bearing, N-bearing, and O- and N-bearing COMs in G31 with other
twenty-seven sources, including other hot molecular cores inside and
outside the Galactic Center, hot corinos, shocked regions, envelopes
around young stellar objects, and quiescent molecular clouds, and with
chemical models. From the comparison with other sources there is not a
unique template for the abundances in hot molecular cores, pointing
towards the importance of the thermal history for the chemistry of the
various sources. The abundances derived from the chemical models are
well in agreement, within a factor ten, with those of G31. From the
analysis of the maps we derived the peak positions of all the
molecular species toward G31. Different species peak at slightly
different positions, and this, together with the different central
velocities of the lines obtained from the spectral fitting, point to
chemical differentiation of selected O-bearing species.
Description:
Tables C.1 to C.15 of the paper. The tables include the transitions used
for the fit of O-bearing and N-bearing molecules detected towards
G31.41+0.31 in the GUAPOS survey.
In the tables the frequencies, Einstein coefficients, Energies of the upper
level, quantum numbers of the upper and lower levels and the optical depths
of the lines calculated using the column density and the excitation
temperature of the best fit are given. The last column is a flag indicating
the transitions used for the mean moment-0 map.
Objects:
-------------------------------------------------------------
RA (2000) DE Designation(s)
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18 47 34.29 -01 12 44.5 G31.41+0.31 = GAL 031.41+00.31
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ch3ohv1.dat 52 8 Transitions of CH3OH vt=1 selected for the fit
c13h3oh.dat 52 14 Transitions of C13H3OH selected for the fit
ch3o18h.dat 52 15 Transitions of CH3O-18-H selected for the fit
ch3cho.dat 52 11 Transitions of CH3CHO selected for the fit
ch3och3.dat 52 75 Transitions of CH3OCH3 selected for the fit
ch3coch3.dat 52 69 Transitions of CH3COCH3 selected for the fit
c2h5oh.dat 52 43 Transitions of C2H5OH selected for the fit
g-glycol.dat 52 8 Transitions of gGg'-(CH2OH)2 selected
for the fit
a-glycol.dat 52 24 Transitions of aGg'-(CH2OH)2 selected for
the fit
ch3cnv1.dat 52 16 Transitions of CH3CN v8=1 selected for the fit
c13h3cn.dat 39 7 Transitions of C13H3CN selected for the fit
ch3c13n.dat 39 3 Transitions of CH3C13N selected for the fit
c2h3cn.dat 52 15 Transitions of C2H3CN selected for the fit
c2h5cn.dat 52 30 Transitions of C2H5CN selected for the fit
c2h5c13n.dat 52 11 Transitions of C2H5C-13-N selected
for the fit
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See also:
J/A+A/644/A84 : GUAPOS I. Identified transitions of C2H4O2 (Mininni+, 2020)
J/A+A/653/A129 : GUAPOS II. Identified transitions of molecules (Colzi+, 2021)
Byte-by-byte Description of file: ch3*h* ch3cnv1* c13h3oh* c2* ?-glycol.dat
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Bytes Format Units Label Explanations
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1- 10 F10.3 MHz RFreq Rest frequency
12- 18 F7.3 s-1 A Einstein coefficient
20- 26 F7.3 K Eu Upper state energy Eu
28- 29 I2 --- Ju Upper state quantum number J
31- 32 I2 --- Kau Upper state quantum number Ka
34- 35 I2 --- Kcu ? Upper state quantum number Kc
37- 38 I2 --- Jl Lower state quantum number J
40- 41 I2 --- Kal Lower state quantum number Ka
43- 44 I2 --- Kcl ? Lower state quantum number Kc
46- 50 F5.3 --- tau Optical depth at the center of the line
52 A1 --- Flag [Y-] Flag: transition used for the
mom-0 mean map
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Byte-by-byte Description of file: c13h3cn.dat ch3c13n.dat
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Bytes Format Units Label Explanations
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1- 10 F10.3 MHz Rfreq Rest frequency
12- 17 F6.3 s-1 E Einstein coefficient
19- 23 F5.2 K Eu Upper state energy E_u
25 I1 --- Ju Upper state quantum number J
27 I1 --- Ku Upper state quantum number K
29 I1 --- Jl Lower state quantum number J
31 I1 --- Kl Lower state quantum number K
33- 37 F5.3 --- tau Optical depth at the center of the line
39 A1 --- Flag [Y-] Flag: transition used for the
mom-0 mean map
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Acknowledgements:
Chiara Mininni, chiara.mininni.astro(at)gmail.com
References:
Mininni et al., Paper I 2020A&A...644A..84M 2020A&A...644A..84M, Cat. J/A+A/644/A84
Colzi et al., Paper II 2021A&A...653A.129C 2021A&A...653A.129C, Cat. J/A+A/653/A129
(End) Patricia Vannier [CDS] 03-Jul-2023