Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The radiation stability of glycine in solid CO2 - in situ laboratory
  measurements with applications to Mars   The detection of biologically important, organic molecules on Mars is an
important goal that may soon be reached. However, the current small number of
organic detections at the Martian surface may be due to the harsh UV and
radiation conditions there. It seems likely that a successful search will
require probing the subsurface of Mars, where penetrating cosmic rays and Solar
energetic particles dominate the radiation environment, with an influence that
weakens with depth. Toward the goal of understanding the survival of organic
molecules in cold radiation-rich environments on Mars, we present new kinetics
data on the radiolytic destruction of glycine diluted in frozen carbon dioxide.
Rate constants were measured in situ with infrared spectroscopy, without
additional sample manipulation, for irradiations at 25, 50, and 75 K with
0.8-MeV protons. The resulting half-lives for glycine in CO2-ice are compared
to previous results for glycine in H2O-ice and show that glycine in CO2-ice is
much less stable in a radiation environment, with destruction rate constants ~
20-40 times higher than glycine in H2O-ice. Extrapolation of these results to
conditions in the Martian subsurface results in half-lives estimated to be less
than 100-200 million years even at depths of a few meters.

18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
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The categories of this paper are: stat
12
The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio