Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurements of Stellar Inclinations for Kepler Planet Candidates II:
  Candidate Spin-Orbit Misalignments in Single and Multiple-Transiting Systems   We present a test for spin-orbit alignment for the host stars of 25 candidate
planetary systems detected by the {\it Kepler} spacecraft. The inclination
angle of each star's rotation axis was estimated from its rotation period,
rotational line broadening, and radius. The rotation periods were determined
using the {\it Kepler} photometric time series. The rotational line broadening
was determined from high-resolution optical spectra with Subaru/HDS. Those same
spectra were used to determine the star's photospheric parameters (effective
temperature, surface gravity, metallicity) which were then interpreted with
stellar-evolutionary models to determine stellar radii. We combine the new
sample with the 7 stars from our previous work on this subject, finding that
the stars show a statistical tendency to have inclinations near 90$^\circ$, in
alignment with the planetary orbits. Possible spin-orbit misalignments are seen
in several systems, including three multiple-planet systems (KOI-304, 988,
2261). Ideally these systems should be scrutinized with complementary
techniques---such as the Rossiter-McLaughlin effect, starspot-crossing
anomalies or asteroseismology---but the measurements will be difficult owing to
the relatively faint apparent magnitudes and small transit signals in these
systems.

5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs