Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-orbit misalignment in the HD80606 planetary system   We recently reported the photometric and spectroscopic detection of the
primary transit of the 111-day-period, eccentric extra-solar planet HD80606 b,
at Observatoire de Haute-Provence, France (Moutou et al. 2009). The whole
egress of the primary transit and a section of its central part were observed,
allowing the measurement of the planetary radius, and evidence for a spin-orbit
misalignment through the observation of the Rossiter-McLaughlin anomaly. The
ingress having not been observed for this long-duration transit, uncertainties
remained in the parameters of the system. We present here a refined, combined
analysis of our photometric and spectroscopic data, together with further
published radial velocities, ground-based photometry, and Spitzer photometry
around the secondary eclipse, as well as new photometric measurements of HD
80606 acquired at Mount Hopkins, Arizona, just before the beginning of the
primary transit. Although the transit is not detected in those new data, they
provide an upper limit for the transit duration, which narrows down the
possible behaviour of the Rossiter-McLaughlin anomaly in the unobserved part of
the transit. We analyse the whole data with a Bayesian approach using a
Markov-chain Monte Carlo integration on all available information. We find R_p
= 0.98 +- 0.03 R_Jup for the planetary radius, and a total primary transit
duration of 11.9 +- 1.3 hours from first to fourth contact. Our analysis
reinforces the hypothesis of spin-orbit misalignment in this system (alignment
excluded at >95 % level), with a positive projected angle between the planetary
orbital axis and the stellar rotation (median solution lambda ~ 50 degrees). As
HD80606 is a component of a binary system, the peculiar orbit of its planet
could result from a Kozai mechanism.

3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas