J/A+A/620/A46 O2 signature in thin and thick O2-H2O ices (Mueller+, 2018)
O2 signature in thin and thick O2-H2O ices.
Mueller B., Giuliano B.M., Bizzocchi L., Vasyunin A.I., Caselli P.
<Astron. Astrophys. 620, A46 (2018)>
=2018A&A...620A..46M 2018A&A...620A..46M (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Spectra, infrared ; Spectroscopy
Keywords: astrochemistry - methods: laboratory: solid state -
techniques: spectroscopic - ISM: molecules -- Infrared: ISM
Abstract:
In this paper we investigate the detectability of the molecular oxygen
in icy dust grain mantles towards astronomical objects.
We present a systematic set of experiments with O2-H2O ice
mixtures designed to disentangle how the molecular ratio affects the
O2 signature in the mid- and near-infrared spectral regions. All the
experiments were conducted in a closed-cycle helium cryostat coupled
to a Fourier transform infrared spectrometer. The ice mixtures
comprise varying thicknesses from 8x10-3 to 3um. The absorption
spectra of the O2-H2O mixtures are also compared to the one of
pure water. In addition, the possibility to detect the O2 in icy
bodies and in the interstellar medium is discussed.
We are able to see the O2 feature at 1551cm-1 even for the most
diluted mixture of H2O:O2=9:1, comparable to a ratio of
O2/H2O=10% which has already been detected in situ in the coma of
the comet 67P/Churyumov-Gerasimenko. We provide an estimate for the
detection of O2 with the future mission of the James Webb Space
Telescope (JWST).
Description:
We present the results of experiments with mixtures of O2 and H2O
with mixture ratios ranging from H2O:O2=9:1 to H2O:O2=1:9. The
absorption spectra were recorded for a KBr substrate temperature of
10K. The spectral range lies between 4000-500cm-1 for the thick
H2O:O2=2:1 ice. For all other experiments the spectral region
ranges from 4800-500cm-1. All spectra were recorded with a
resolution of 2cm-1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 61 16 List of absorption spectra
o2-h2o-ice/* . 16 Individual absorption spectra
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- FileName Name of the file in subdirectory o2-h2o-ice
20- 61 A42 --- Title Title of the absorption spectrum file
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Byte-by-byte Description of file: o2-h2o-ice/*
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Bytes Format Units Label Explanations
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1- 10 F10.5 cm-1 Wavenumber Wavenumber
12- 20 F9.6 --- Absorbance Absorbance
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Acknowledgements:
Birgitta Mueller, bmueller(at)mpe.mpg.de
(End) Birgitta Mueller [MPE], Patricia Vannier [CDS] 24-Oct-2018