Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A New Very Cool White Dwarf Discovered by the Sloan Digital Sky Survey   Early data taken during commissioning of the SDSS have resulted in the
discovery of a very cool white dwarf. It appears to have stronger collision
induced absorption from molecular hydrogen than any other known white dwarf,
suggesting it has a cooler temperature than any other. While its distance is
presently unknown, it has a surprisingly small proper motion, making it
unlikely to be a halo star. An analysis of white dwarf cooling times suggests
that this object may be a low-mass star with a helium core. The SDSS imaging
and spectroscopy also recovered LHS 3250, the coolest previously known white
dwarf, indicating that the SDSS will be an effective tool for identifying these
extreme objects.

19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg