Congresos y reuniones científicas
Título:
An upper limit for the mass los rate of HD 209458b
Autor/es:
SCHNEITER, E. M.; VELAZQUEZ, P. F.; BLANCO-CANO, X.; ESQUIVEL, A.; RAGA, A. C.
Lugar:
Acapulco, Guerrero, Mexico
Reunión:
Congreso; American Geophysical Union, Spring Meeting 2007; 2007
Institución organizadora:
AGU
Resumen:
HD 209458b is a Jovian like planet orbiting around a star with similar
characteristic to the Sun. It was discovered by its repeated transit
across the stellar disk. The orbital period is 3.5 days, with a mean
distance to the star of 0.045 AU (closer than Mercury to the Sun in our
system). The peculiar characteristic of this system is that the planet
shows an apparent larger size when observed in Lyman α (1214-1217
A) than in optical wavelength (Na I). This discrepancy is thought to be
due to the existence of an extended upper atmosphere or wake (comet like
wake). In this work we present 3D numerical simulations of this system
(done with the adaptive grid Yguazú-a code), and study the
absorption produced by this extended atmosphere. The atmosphere is
modelled as a wind outgoing from the surface of the planet at velocities
of the order of the escape velocity (60 km s-1). Four runs where carried
out considering different mass loss rates for the planet in the range [
]MSUNyr-1. By comparing the model with the observations, we found an
upper limit for the mass loss rate of HD 209458b (previous works only
found a lower limit. We compare HD 209458b characteristics with solar
system planets.