Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Water and Methanol Ice in L1544   Methanol and complex organic molecules have been found in cold starless
cores, where a standard warm-up scenario would not work because of the absence
of heat sources. A recent chemical model attributed the presence of methanol
and large organics to the efficient chemical desorption and a class of
neutral-neutral reactions that proceed fast at low temperatures in the gas
phase. The model calls for a high abundance of methanol ice at the edge of the
CO freeze-out zone in cold cloud cores. We performed medium resolution
spectroscopy toward 3 field stars behind the starless core L1544 at 3 $\mu$m to
constrain the methanol ice abundance and compare it with the model predictions.
One of the field stars shows a methanol-ice abundance of 11% with respect to
water ice. This is higher than the typical methanol abundance previously found
in cold cloud cores (4%), but is 4.5 times smaller than predicted. The reason
for the disagreement between the observations and the model calculations is not
yet understood.

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The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph