The Subaru Seminar is
usually held in Room 104 of the Hilo Base Facility, adjacent
to the main lobby. Everyone is welcome to attend. If you are
interested in giving a seminar, please contact Subaru seminar organizers
(Tomonori Usuda, Kumiko S. Usuda, Masayuki Akiyama)
by email : sseminar_at_subaru.naoj.org (please change"_at" to @).
July 11, Wednesday at 11:00 am
" Testing Planet Migration Theories by Observations of Transiting Exoplanetary Systems "
(University of Tokyo)
There are over 200 extrasolar planets that have been discovered so far.
The discovery and characterization of extrasolar planets have revealed
diversity of planetary systems. For example, most of extrasolar planets
are known to have totally different circumstances from our Solar System;
a significant proportion of those planets lie at semi-major axes of less
than about 0.1 AU ("hot Jupiters") and/or have appreciable eccentricities
of 0.2 - 0.9 ("eccentric planets").
It is commonly believed that hot Jupiters originally formed at larger
orbital distances and migrated inward during the planet formation epoch.
The proposed migration mechanisms involve gravitational interactions with
the protoplanetary disk (disk-planet interaction) and other giant planets
(planet-planet interaction). However, the relative importance of the
migration mechanisms is still unclear.
On the other hand, the alignment of the stellar spin axis and the planetary
orbital axis (spin-orbit alignment) is known to be an useful diagnostic for
discriminating planet formation mechanisms. One can measure the spin-orbit
alignment by exploiting the Rossiter-McLaughlin effect in transiting
We recently succeeded in detecting the Rossiter-McLaughlin effect in the
transiting exoplanetary system TrES-1 using Subaru/HDS. It is the third case
for which the Rossiter-McLaughlin effect has been detected in a transiting
exoplanetary system, and the first demonstration that such measurements are
possible for relatively faint (V~12) host stars. I will review the
backgrounds and our recent results/future prospects of Subaru observations.
Narita et al. 2007, PASJ in press, astro-ph/0702707
Seminars are also held at JAC,