Spin-orbit inclinations of the exoplanetary systems HAT-P-8b, HAT-P-9b, HAT-P-16b, and HAT-P-23b

C. MOUTOU; R. F. DÍAZ; S. UDRY; G. HÉBRARD; F. BOUCHY; A. SANTERNE; D. EHRENREICH; L. ARNOLD; I. BOISSE; X. BONFILS; X. DELFOSSE; A. EGGENBERGER; T. FORVEILLE; A. M. LAGRANGE; C. LOVIS; P. MARTÍNEZ; F. PEPE; C. PERRIER; D. QUELOZ; N. C. SANTOS; D. SÉGRANSAN; D. TOUBLANC; J. P. TRONCIN; M. VANHUYSSE; A. VIDAL-MADJAR

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2011 vol. 533 p. 1 - 10

0004-6361

We report the measurement of the spin-orbit angle of the extra-solar planets HAT-P-8 b, HAT-P-9 b, HAT-P-16 b, and HAT-P-23 b, based on spectroscopic observations performed at the Observatoire de Haute-Provence with the SOPHIE spectrograph on the 1.93-m telescope. Radial velocity measurements of the Rossiter-McLaughlin effect show the detection of an apparent prograde, aligned orbit for all systems. The projected spin-orbit angles are found to be λ = -17°+9.2-11.5, -16° ± 8°, -10° ± 16°, and +15° ± 22° for HAT-P-8, HAT-P-9, HAT-P-16, and HAT-P-23, respectively, with corresponding projected rotational velocities of 14.5 ± 0.8, 12.5 ± 1.8, 3.9 ± 0.8, and 7.8 ± 1.6 km s-1. These new results increase to 37 the number of accurately measured spin-orbit angles in transiting extrasolar systems. We conclude by drawing a tentative picture of the global behaviour of orbital alignement, involving the complexity and diversity of possible mechanisms.