J/A+A/551/A28 H2CO and CO in 4 molecular clouds (Tang+, 2013)
The relation of H2CO, 12CO, and 13CO in molecular clouds.
Tang X.D., Esimbek J., Zhou J.J., Wu G., Ji W.G., Okoh D.
<Astron. Astrophys., 551, A28 (2013)>
=2013A&A...551A..28T 2013A&A...551A..28T (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Carbon monoxide
Keywords: ISM: clouds - ISM: molecules - stars: formation
Abstract:
We seek to understand how the 4.8GHz formaldehyde absorption line is
distributed in the MON R2, S156, DR17/L906, and M17/M18 regions. More
specifically, we look for the relationship among the H2CO, 12CO,
and 13CO spectral lines. The four regions of MON R2 (60'x90'), S156
(50'x70'), DR17/L906 (40'x60'), and M17/M18 (70'x80') were observed
for H2CO (beam 10'), H110α recombination (beam 10'), 6 cm
continuum (beam 10'), 12CO (beam 1'), and 13CO (beam 1'). We
compared the H2CO, 12CO, 13CO, and continuum distributions, and
also the spectra line parameters of H2CO, 12CO, and 13CO. Column
densities of H2CO, 13CO, and H2 were also estimated. We found
out that the H2CO distribution is similar to the 12CO and the
13CO distributions on a large scale. The correlation between the
13CO and the H2CO distributions is better than between the 12CO
and H2CO distributions. The H2CO and the 13CO tracers
systematically provide consistent views of the dense regions. Their
maps have similar shapes, sizes, peak positions, and molecular spectra
and present similar central velocities and line widths. Such good
agreement indicates that the H2CO and the 13CO arise from similar
regions.
Description:
From September 2010 to August 2011, we observed the H2CO line, the
H110α line, and the 6cm continuum with the Nanshan 25m radio
telescope of Xinjiang Astronomical Observatory.
From 15 to 26 May 2011, the 12CO and 13CO observations of the four
regions were carried out with the 13.7m millimeter wave telescope of
Purple Mountain Observatory in Delingha.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 78 4 Source positions
tableb2.dat 69 11 Parameters of the H110α recombination line
tableb3.dat 63 211 Parameters of the H2CO (110-111)
absorption line
tableb4.dat 73 382 *Parameters of the 12CO (1-0) and 13CO (1-0)
emission lines
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Note on tableb4.dat: Parameters listed concern the simultaneously observed
12CO and 13CO emission line.
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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- 9 A9 --- Source Source name
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min Rmh Right ascension (J2000)
17- 21 F5.2 s RAs Right ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 33 F4.1 arcsec DEs Declination (J2000)
35- 36 I2 arcmin SizeRA Size along RA
37 A1 --- --- [x]
38- 39 I2 arcmin SizeDE Size along DE
41- 78 A38 --- Ref References
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Source Source name
12- 14 I3 arcmin OffX Offset in RA
15 A1 --- --- [,]
17- 19 I3 arcmin OffY Offset in DE
21- 25 F5.2 K.km/s Flux H110α recombination line flux
27- 30 F4.2 K.km/s e_Flux rms uncertainty on Flux
33- 36 F4.1 km/s Vel H110α recombination line velocity
38- 40 F3.1 km/s e_Vel rms uncertainty on Vel
43- 46 F4.1 km/s Width H110α recombination line width
48- 50 F3.1 km/s e_Width rms uncertainty on Width
53- 56 F4.2 K TL H110α recombination line antenna
temperature
58- 62 F5.2 K TC H110α recombination line continuum
brightness temperature
65- 69 I5 K T*e H110α recombination line local
thermodynamic equilibrium (LTE)
electron temperature
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Byte-by-byte Description of file: tableb3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Source Source name
12- 14 I3 arcmin OffX Offset in RA
15 A1 --- --- [,]
17- 19 I3 arcmin OffY Offset in DE
21- 25 F5.2 K.km/s Flux ?=- H2CO absorption line flux (1)
27- 30 F4.2 K.km/s e_Flux ? rms uncertainty on Flux
32- 36 F5.1 km/s Vel ?=- H2CO absorption line velocity (1)
38- 40 F3.1 km/s e_Vel ? rms uncertainty on Vel
43- 46 F4.1 km/s Width ?=- H2CO absorption line width (1)
48- 50 F3.1 km/s e_Width ? rms uncertainty on Width
53- 57 F5.2 K TL ?=- H2CO absorption line antenna
temperature (1)
59- 63 F5.2 K TC ? H2CO absorption line continuum
brightness temperature
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Note (1): "---" indicates that the corresponding spectra could not be detected
or the line peak intensity is less than 0.02K.
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Byte-by-byte Description of file: tableb4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Source Source name
12- 14 I3 arcmin OffX Offset in RA
15 A1 --- --- [,]
17- 19 I3 arcmin OffY Offset in DE
21- 25 F5.2 K.km/s Flux12 ?=- 12CO(1-0) flux
27- 30 F4.2 K.km/s e_Flux12 ?=- rms uncertainty on Flux12
32- 36 F5.1 km/s Vel12 ?=- 12CO(1-0) velocity (1)
38- 41 F4.1 km/s Width12 ?=- 12CO(1-0) width (1)
43- 46 F4.2 K TL12 ?=- 12CO(1-0) antenna temperature
48- 52 F5.2 K.km/s Flux13 ?=- 13CO(1-0) flux
54- 57 F4.2 K.km/s e_Flux13 ?=- rms uncertainty on Flux13
59- 63 F5.1 km/s Vel13 ?=- 13CO(1-0) velocity (1)
65- 68 F4.1 km/s Width13 ?=- 13CO(1-0) width (1)
70- 73 F4.2 K TL13 ?=- 13CO(1-0) antenna temperature
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Note (1): The 12CO and 13CO line velocities uncertainty together are about
0.2km/s and the line width uncertainty together are about 0.2km/s.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 19-Dec-2017