J/A+A/587/A118 N2H+, N2D+ and C17O spectra in Ophiuchus (Punanova+, 2016)
Deuterium fractionation in the Ophiuchus molecular cloud.
Punanova A., Caselli P., Pon A., Belloche A., Andre P.
<Astron. Astrophys. 587, A118 (2016)>
=2016A&A...587A.118P 2016A&A...587A.118P (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Molecular clouds ;
Spectra, millimetric/submm
Keywords: stars: formation - ISM: kinematics and dynamics - ISM: clouds -
ISM: abundances - ISM: molecules
Abstract:
In cold (T<25K) and dense (nH>104cm-3) interstellar clouds,
molecules such as CO are significantly frozen onto dust grain
surfaces. Deuterium fractionation is known to be very efficient in
these conditions as CO limits the abundance of H3+, which is the
starting point of deuterium chemistry. In particular, N2D+ is an
excellent tracer of dense and cold gas in star- forming regions.
We measure the deuterium fraction, RD, and the CO depletion factor,
fd, towards a number of starless and protostellar cores in the L1688
region of the Ophiuchus molecular cloud and search for variations
based upon environmental differences across L1688. The kinematic
properties of the dense gas traced by the N2H+ and N2D+ (1-0)
lines are also discussed.
Deuterium fraction has been measured via observations of the J=1-0
transition of N2H+ and N2D+ towards 33 dense cores in different
regions of L1688. We estimated the CO depletion factor using
C17O(1-0) and 850 micron dust continuum emission from the SCUBA
survey. We carried out all line observations with the IRAM 30 meter
antenna.
Description:
N2H+(1-0), N2D+, C17O (1-0) and (2-1) single spectra towards
dense cores in L1688 obtained with the IRAM 30m antenna. The files
contain only spectra where lines were detected. The list of objects
and observed lines is in Table A.1. of the paper.
Objects:
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RA (2000) DE Designation(s)
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16 28 06 -24 32.5 LDN 1688 = NAME OPHIUCHUS MOLECULAR CLOUD
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
lc17o10.dat 119 37 Informations on L1688_C17O10.fit file
lc17o21.dat 126 31 Informations on L1688_C17O21.fit file
ln2dp10.dat 73 24 Informations on L1688_N2D+10.fit file
ln2dp21.dat 87 24 Informations on L1688_N2D+21.fit file
ln2hp10.dat 47 7 Informations on L1688_N2H+10.fit file
fits/* . 5 *Individual fits files
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Note on fits/*: The fits files produced with CLASS (Continuum and Line Analysis
Single-Dish Software http://www.iram.fr/IRAMFR/GILDAS) from .30m files.
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See also:
J/A+A/472/519 : N2H+(1-0) maps of Ophiuchus main cloud (Andre+, 2007)
Byte-by-byte Description of file: lc17o10.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Naxis Number of observed frequencies
6- 9 I4 --- Scan Number of scans
11- 18 A8 --- Core Dense core name
22- 31 A10 --- Source Source name in fits header
33- 44 A12 --- Tel Telescop
46- 52 F7.3 deg RAdeg Source right ascension (J2000) at Epoch Ep
54- 61 F8.4 deg DEdeg Source declination (J2000) at Epoch Ep
63- 66 I4 --- Ep Epoch of position
68- 73 F6.1 arcsec oRA Offset in right ascension in respect to the
Source position
75- 80 F6.1 arcsec oDE Offset in Declination in respect to the
Source position
82- 93 E12.6 Hz ImageFreq [1.15356e+11] Image frequency
95- 98 I4 km/s Vel Velocity
101-108 F8.4 km/s deltaV δV
110-119 A10 "date" Obs.Date Observation date
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Byte-by-byte Description of file: lc17o21.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Naxis Number of observed frequencies
6- 9 I4 --- Scan Number of scans
11- 18 A8 --- Core Dense core name
22- 31 A10 --- Source Source name in fits header
33- 44 A12 --- Tel Telescop
46- 52 F7.3 deg RAdeg Source right ascension at Epoch
54- 61 F8.4 deg DEdeg Source declination at Epoch
63- 66 I4 yr Epoch Epoch for position
68- 73 F6.1 arcsec oRA Offset in right ascension in respect to the
Source position
75- 80 F6.1 arcsec oDE Offset in declination in respect to the
Source position
82- 93 E12.6 Hz RestFreq [2.24714e+11] Rest frequency
95-106 E12.6 Hz ImageFreq Image frequency
108-115 F8.4 km/s deltaV δV
117-126 A10 "date" Obs.Date Observation date
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Byte-by-byte Description of file: ln2dp10.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Naxis Number of observed frequencies
6- 9 I4 --- Scan Number of scans
11- 18 A8 --- Source Source name in fits header
20- 26 F7.3 deg RAdeg Right ascension (J2000)
28- 35 F8.4 deg DEdeg Declination (J2000)
37- 48 E12.6 Hz ImageFreq Image frequency
50- 54 I5 km/s Vel Velocity
56- 62 F7.4 km/s deltaV δV
64- 73 A10 "date" Obs.Date Observation date
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Byte-by-byte Description of file: ln2dp21.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Naxis Number of observed frequencies
6- 9 I4 --- Scan Number of scans
11- 18 A8 --- Source Source name in fits header
20- 26 F7.3 deg RAdeg Right ascension (J2000)
28- 35 F8.4 deg DEdeg Declination (J2000)
37- 49 E13.6 Hz RestFreq [1.54217e+11] Rest frequency
51- 62 E12.6 Hz ImageFreq [1.62734e+11] Image frequency
64- 68 I5 km/s Vel Velocity
70- 76 F7.3 km/s deltaV δV
78- 87 A10 --- Obs.Date Observation date
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Byte-by-byte Description of file: ln2hp10.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Scan Number of scans
6- 11 A6 --- Source Source name in fits header
13- 19 F7.3 deg RAdeg Right ascension (J2000)
21- 28 F8.4 deg DEdeg Declination (J2000)
30- 41 E12.6 Hz ImageFreq [9.61700e+10] Image frequency
43- 47 I5 km/s Vel Velocity
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Acknowledgements:
Anna Punanova, punanova(at)mpe.mpg.de
(End) Patricia Vannier CDS 25-Jan-2016