Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutron star envelopes and thermal radiation from the magnetic surface   The thermal structure of neutron star envelopes is discussed with emphasis on
analytic results. Recent progress on the effect of chemical constitution and
high magnetic fields on the opacities and the thermal structure is further
reviewed in view of the application to pulsar cooling and magnetars.

4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an