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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Estimating stellar rotation from starspot detection during planetary transits

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Author(s):
Silva-Valio, Adriana [1]
Total Authors: 1
Affiliation:
[1] Univ Presbiteriana Mackenzie, CRAAM, BR-01302907 Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: Astrophysical Journal Letters; v. 683, n. 2, p. L179-L182, AUG 20 2008.
Web of Science Citations: 47
Abstract

A new method for determining the stellar rotation period is proposed here, based on the detection of starspots during transits of an extrasolar planet orbiting its host star. As the planet eclipses the star, it may pass in front of a starspot which will then make itself known through small flux variations in the transit light curve. If we are lucky enough to catch the same spot on two consecutive transits, it is possible to estimate the stellar rotational period. This method is successfully tested on transit simulations on the Sun yielding the correct value for the solar period. By detecting two starspots on more than one transit of HD 209458 observed by the Hubble Space Telescope, it was possible to estimate a period of either 9.9 or 11.4 days for the star, depending on which spot is responsible for the signature in the light curve a few transits later. Comparison with period estimates of HD 209458 reported in the literature indicates that 11.4 days is the most likely stellar rotation period. (AU)

FAPESP's process: 06/50654-3 - Investigation of high energy and plasma astrophysics phenomena: theory, observation, and numerical simulations
Grantee:Elisabete Maria de Gouveia Dal Pino
Support type: Research Projects - Thematic Grants