J/ApJ/849/139 Interstellar acetone (CH3COCH3) in 3 regions (Zou+, 2017)
Observation and analysis of interstellar acetone in GAL 31.41+0.31,
GAL 034.3+00.2, and GAL 10.47+00.03.
Zou L., Widicus Weaver S.L.
<Astrophys. J., 849, 139-139 (2017)>
=2017ApJ...849..139Z 2017ApJ...849..139Z (SIMBAD/NED BibCode)
ADC_Keywords: Star Forming Region; Molecular data; Millimetric/submm sources
Keywords: astrochemistry; ISM: molecules; line: identification; molecular data
Abstract:
We present observations of interstellar acetone (CH3COCH3)
detected in broadband line surveys in the 1.3mm band from the Caltech
Submillimeter Observatory (CSO). The observations were conducted
toward three massive star-forming regions: GAL31.41+0.31,
GAL034.3+00.2, and GAL10.47+00.03. Numerous acetone lines were
detected in these three sources. The results were analyzed using the
assumption of local thermodynamic equilibrium. These results
rigorously confirm the previous reports of acetone detections in
GAL31.41+0.31 and GAL10.47+00.03, and add a new acetone detection in
GAL034.3+00.2. Source-averaged column densities for acetone were
determined to be 1.1(6)x1016cm-2 for GAL31.41+0.31,
6.4(3)x1016cm-2 for GAL10.47+00.03, and 1.3(3)x1015cm-2 for
GAL034.3+00.2. The rotational temperatures of acetone in these three
sources range from 49 to 132K, which suggests a complicated formation
mechanism for interstellar acetone.
Description:
Observations of the three sources were performed in the summer of 2012
with the facility 230GHz wideband receiver, used with the facility
Fast Fourier Transform Spectrometer (FFTS) on the 10.4m Leighton
Telescope at the Caltech Submillimeter Observatory (CSO); these
observations have been described in detail by Widicus Weaver+ (2017,
J/ApJS/232/3). The total spectral coverage varied with each source,
but in general ranged from ∼220-265GHz.
Objects:
------------------------------------------------------------------
RA (ICRS) DE Designation(s)
------------------------------------------------------------------
18 47 34.49 -01 12 40.3 GAL31.41+0.31 = BGPS G031.414+00.307
18 53 18.54 +01 14 57.9 GAL34.3+0.2 = IRAS 18507+0110
18 08 38.4 -19 51 52 GAL10.47+0.03 = GAL 010.47+00.03
------------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 79 3 Observational parameters
table3.dat 135 3 Beam-averaged and source-averaged fit results of
acetone lines using the GOBASIC program
(Rad+ 2016, J/A+A/585/A23)
table4.dat 81 392 Brightest acetone lines observed in these sources
--------------------------------------------------------------------------------
See also:
J/A+A/585/A23 : GOBASIC code (Rad+, 2016)
J/A+A/568/A65 : NGC 7129 FIRS 2 interferometric 1-D spectrum (Fuente+, 2014)
J/A+A/532/A32 : HCOOCH3 map of Orion-KL (Favre+, 2011)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Source name
17- 27 A11 "Y/M/D" Date First UT date of observation
28 A1 --- --- [-]
29- 30 I2 d Day2 Last day of observation
32- 33 I2 h RAh Hour of right ascension (J2000)
35- 36 I2 min RAm Minute of right ascension (J2000)
38- 42 F5.2 s RAs Second of right ascension (J2000)
44 A1 --- DE- Sign of declination (J2000)
45- 46 I2 deg DEd Degree of declination (J2000)
48- 49 I2 arcmin DEm Arcminute of declination (J2000)
51- 54 F4.1 arcsec DEs Arcsecond of declination (J2000)
56- 59 F4.1 km/s Vlsr [58/97] Local standard of rest velocity
61- 63 I3 K Tsys1 [175/196] Lower range of telescope system
temperature
64 A1 --- --- [-]
65- 67 I3 K Tsys2 [265/344] Upper range of telescope system
temperature
69- 73 F5.3 --- tau1 [0.04/0.06] Lower range of atmospheric optical
at 225GHz
74 A1 --- --- [-]
75- 79 F5.3 --- tau2 [0.08/0.2] Upper range of atmospheric optical
at 225GHz τ
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Source name
17- 20 I4 --- N Number of transitions included in the fit
22- 30 A9 K Eup State energy Eup/k
32- 37 F6.4 --- tau-b [0.001/0.005] Beam-averaged maximum acetone
optical depth (τmax)
39- 45 E7.3 cm-2 NT-b Beam-averaged column density
47- 53 E7.3 cm-2 e_NT-b 1σ uncertainty on NT-b
55- 57 I3 K Trot-b [62/137] Beam-averaged rotational temperature
59- 60 I2 K e_Trot-b 1σ uncertainty on Trot-b
62- 65 F4.1 km/s FWHM-b Beam-averaged line width
67- 69 F3.1 km/s e_FWHM-b 1σ uncertainty on FWHM-b
70 A1 --- f_FWHM-b a: The FWHM was fixed to 10.0km/s
72- 75 F4.1 km/s dVel-b Beam-averaged velocity shift relative to the
Vlsr and assumed source size θ
77- 79 F3.1 km/s e_dVel-b 1σ uncertainty on dVel-b
81- 87 A7 arcsec theta Source size θ
88 A1 --- f_theta Flag on θ (1)
90- 95 F6.4 --- tau [0.02/1.2] Source-averaged maximum acetone
optical depth (τmax)
97-102 E6.2 cm-2 NT Source-averaged column density
104-109 E6.2 cm-2 e_NT 1σ uncertainty on NT
111-113 I3 K Trot [49/132] Source-averaged rotational temperature
115-116 I2 K e_Trot 1σ uncertainty on Trot
118-121 F4.1 km/s FWHM Source-averaged line width
123-125 F3.1 km/s e_FWHM 1σ uncertainty on FWHM
126 A1 --- f_FWHM a: The FWHM was fixed to 10.0km/s
128-131 F4.1 km/s dVel Source-averaged velocity shift relative to the
Vlsr and assumed source size θ
133-135 F3.1 km/s e_dVel 1σ uncertainty on dVel
--------------------------------------------------------------------------------
Note (1): Flag as follows:
b = Methyl formate (HCOOCH3) size in the 1.3mm band
(Calcutt+ 2014MNRAS.443.3157C 2014MNRAS.443.3157C).
c = Acetic acid (CH3COOH) size in the 3mm band
(Remijan+ 2003ApJ...590..314R 2003ApJ...590..314R)
d = Acetone (CH3COCH3) size in the 860um band, measured from the image
(Rolffs+ 2011A&A...536A..33R 2011A&A...536A..33R).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 F11.4 MHz Freq [220352.5/265017.3] Catalog frequency
13- 23 F11.4 MHz GAL31.41 [220352.3/265017] GAL 31.41+0.31 line center
frequency
25- 35 F11.4 MHz GAL034.3 [220351.7/265016.3] GAL 034.3+00.2 line center
frequency
37- 47 F11.4 MHz GAL10.47 [220353.2/265018.1] GAL 10.47+00.03 line center
frequency
49- 56 F8.4 K Eup [40.3/600.3] Upper state energy
58- 78 A21 -- TNum Transition quantum numbers in the format
J"Ka",Kc"-J'Ka',Kc'.
80- 81 A2 -- Par Transition parity label
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 15-Jun-2018