J/A+A/585/A36 Deuterated water in prestellar cores (Quenard+, 2016)
Detectability of deuterated water in prestellar cores.
Quenard D., Taquet V., Vastel C., Caselli P., Ceccarelli C.
<Astron. Astrophys. 585, A36 (2016)>
=2016A&A...585A..36Q 2016A&A...585A..36Q (SIMBAD/NED BibCode)
ADC_Keywords: Radio lines ; Line Profiles ; Radial velocities
Keywords: ISM: abundances - astrochemistry - line: identification -
ISM: molecules - ISM: individual objects: L1544
Abstract:
We report on new APEX observations of the ground state 10,1-00,0
HDO transition at 464.92452GHz toward the prestellar core L1544. The
line is undetected and we present an extensive study on the conditions
for its detectability in cold and dense cloud cores. The water and
deuterated water abundances have been estimated using an advanced
chemical model simplified for the limited number of reactions or
processes that are active in cold regions (<15K). We use the LIME
radiative transfer code to compute the expected intensity and profile
of both H2O and HDO lines and compare them with the observations. We
present several ad hoc profiles that best-fit the observations and
compare the profiles with results from an astrochemical modeling,
coupling gas phase and grain surface chemistry. Our comparison between
observations, radiative transfer and chemical modeling shows the
limits of detectability for singly deuterated water with single-dish
telescopes as well as interferometric observations.
Description:
Line profiles of the ortho-H2O 11,0-10,1 (Herschel/HIFI) and HDO
1,0,1-0,0,0 (APEX) transitions at 556.93607 and 464.92452GHz
respectively are presented. For each line, we provide the intensity of
the main beam temperature (Tmb) in Kelvin as a function of the rest
frequency in GHz. The Vlsr of the source is 7.2km/s.
Objects:
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RA (2000) DE Designation(s)
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05 04 18 +25 11.1 L1544 = LDN 1544
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
h2o.dat 27 927 Line profile of the H2O transition
hdo.dat 27 202 Line profile of the HDO transition
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Byte-by-byte Description of file: h2o.dat hdo.dat
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Bytes Format Units Label Explanations
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1- 15 E15.10 MHz Freq Rest frequency
17- 27 E11.5 K Tmb Main beam temperature
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Acknowledgements:
Charlotte Vastel, cvastel(at)irap.omp.eu
(End) David Quenard [IRAP, France], Patricia Vannier [CDS] 04-Nov-2015