Periastron Precession Measurements in Transiting Extrasolar Planetary Systems at the Level of General Relativity
Online Access
http://arxiv.org/abs/0806.0629Abstract
Transiting exoplanetary systems are surpassingly important among the planetary systems since they provide the widest spectrum of information for both the planet and the host star. If a transiting planet is on an eccentric orbit, the duration of transits T_D is sensitive to the orientation of the orbital ellipse relative to the line of sight. The precession of the orbit results in a systematic variation in both the duration of individual transit events and the observed period between successive transits, P_obs. The periastron of the ellipse slowly precesses due to general relativity and possibly the presence of other planets in the system. This secular precession can be detected through the long-term change in P_obs (transit timing variations, TTV) or in T_D (transit duration variations, TDV). We estimate the corresponding precession measurement precision for repeated future observations of the known eccentric transiting exoplanetary systems (XO-3b, HD 147506b, GJ 436b and HD 17156b) using existing or planned space-borne instruments. The TDV measurement improves the precession detection sensitivity by orders of magnitude over the TTV measurement. We find that TDV measurements over a ~4 year period can typically detect the precession rate to a precision well exceeding the level predicted by general relativity.Comment: Accepted for publication in MNRAS, 8+epsilon pages, 2 figures
Date
2008-06-03Type
textIdentifier
oai:arXiv.org:0806.0629http://arxiv.org/abs/0806.0629
MNRAS 389, 191-198 (2008)
doi:10.1111/j.1365-2966.2008.13512.x
DOI
10.1111/j.1365-2966.2008.13512.xae974a485f413a2113503eed53cd6c53
10.1111/j.1365-2966.2008.13512.x