Ballot, J.; Gizon, L.; Samadi, R.; Vauclair, G.; Benomar, O.; Bruntt, H.; Mosser, B.; Stahn, T.; Verner, G. A.; Campante, T. L.; García, R. A.; Mathur, S.; Salabert, D.; Gaulme, P.; Régulo, C.; Roxburgh, I. W.; Appourchaux, T.; Baudin, F.; Catala, C.; Chaplin, W. J.; Deheuvels, S.; Michel, E.; Bazot, M.; Creevey, O.; Dolez, N.; Elsworth, Y.; Sato, K. H.; Vauclair, S.; Auvergne, M.; Baglin, A.
Referencia bibliográfica
Astronomy and Astrophysics, Volume 530, id.A97
Fecha de publicación:
6
2011
Revista
Número de citas
95
Número de citas referidas
62
Descripción
Context. The star HD 52265 is a G0V metal-rich
exoplanet-host star observed in the seismology field of the CoRoT space
telescope from November 2008 to March 2009. The satellite collected 117
days of high-precision photometric data on this star, showing that it
presents solar-like oscillations. HD 52265 was also observed in
spectroscopy with the Narval spectrograph at the same epoch.
Aims: We characterise HD 52265 using both spectroscopic and seismic
data. Methods: The fundamental stellar parameters of HD 52265
were derived with the semi-automatic software VWA, and the projected
rotational velocity was estimated by fitting synthetic profiles to
isolated lines in the observed spectrum. The parameters of the observed
p modes were determined with a maximum-likelihood estimation. We
performed a global fit of the oscillation spectrum, over about ten
radial orders, for degrees l = 0 to 2. We also derived the properties of
the granulation, and analysed a signature of the rotation induced by the
photospheric magnetic activity. Results: Precise determinations
of fundamental parameters have been obtained: Teff = 6100
± 60 K, log g = 4.35 ± 0.09, [M/H] = 0.19 ± 0.05,
as well as vsini=3.6+0.3-1.0kms. We have measured
a mean rotation period Prot = 12.3 ± 0.15 days, and
find a signature of differential rotation. The frequencies of 31 modes
are reported in the range 1500-2550 μHz. The large separation
exhibits a clear modulation around the mean value Dnu=98.3 ± 0.1
μHz. Mode widths vary with frequency along an S-shape with a clear
local maximum around 1800 μHz. We deduce lifetimes ranging between
0.5 and 3 days for these modes. Finally, we find a maximal bolometric
amplitude of about 3.96 ± 0.24 ppm for radial modes.
The CoRoT space mission, launched on December 27th 2006, has been
developed and is operated by CNES, with the contribution of Austria,
Belgium, Brazil, ESA (RSSD and Science Programme), Germany and Spain.
Proyectos relacionados
Sismología Solar y Estelar y Búsqueda de Exoplanetas
Los objetivos genéricos de este Proyecto son: 1) el estudio de la estructura y dinámica del interior solar, 2) la extensión de dicho estudio al caso de otras estrellas, 3) la búsqueda y caracterización de planetas extrasolares por métodos fotométricos (principalmente mediante el método de tránsitos) y espectroscópico (variaciones en la velocidad
Savita
Mathur