Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A reconnaissance of the possible donor stars to the Kepler supernova   The identity of Type Ia supernova progenitors remains a mystery, with various
lines of evidence pointing towards either accretion from a non-degenerate
companion, or the rapid merger of two degenerate stars leading to the
thermonuclear destruction of a white dwarf. In this paper we spectroscopically
scrutinize 24 of the brightest stars residing in the central 38" x 38" of the
SN 1604 (Kepler) supernova remnant to search for a possible surviving companion
star. We can rule out, with high certainty, a red giant companion star - a
progenitor indicated by some models of the supernova remnant. Furthermore, we
find no star that exhibits properties uniquely consistent with those expected
of a donor star down to L>10Lsun. While the distribution of star properties
towards the remnant are consistent with unrelated stars, we identify the most
promising candidates for further astrometric and spectroscopic follow-up. Such
a program would either discover the donor star, or place strong limits on
progenitor systems to luminosities with L<<Lsun.

19
The categories of this paper are: eess
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
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th