Norio Narita

Abstract We present the first evidence of a retrograde orbit of a transiting exoplanet HAT-P-7b. The discovery is based on a measurement of the Rossiter–McLaughlin effect with the Subaru HDS during a transit of HAT-P-7b, which occurred on 2008 May 30 UT. Our best-fit model shows that the spin–orbit alignment angle of this planet is $\lambda$$=$$-132.^\circ 6^{+\timeform{10.^\circ 5}}_{-\timeform{16.^\circ3}}$. The existence of such a retrograde planet has been predicted by recent planetary migra

We report a development of a multicolor simultaneous camera for the 188-cm telescope at Okayama Astrophysical Observatory in Japan. The instrument, named MuSCAT (Multicolor Simultaneous Camera for studying Atmospheres of Transiting exoplanets), has a capability of three-color simultaneous imaging in optical wavelengths where CCDs are sensitive. MuSCAT is equipped with three 1024 × 1024 pixel CCDs which can be controlled independently. The three CCDs detect lights in g2′ (400 to 550 nm), r2′ (550

We report the development of MuSCAT3, a four channel simultaneous imager installed on the 2m Faulkes Telescope North at Haleakala Observatory on Maui, Hawai’i. MuSCAT3 has a capability of 4-color simultaneous imaging in g (400–550 nm), r (550–700 nm), i (700–820 nm), and <i>z</i>_s (820–920 nm) bands with four independent 2048×2048 pixel CCDs, each having a field of view of 9.1×9.1 arcmin² with a pixel scale of 0.27 arcsec per pixel. The development of MuSCAT3 started from S

Abstract We present simultaneous photometric and spectroscopic observations of HD17156b spanning a transit on 2007 November 12 (UT). This system is of special interest because of its 21 d period (unusually long for a transiting planet) and its high orbital eccentricity of 0.67. By modeling the Rossiter–McLaughlin effect, we find the angle between the sky projections of the orbital axis and the stellar rotation axis to be $62^{\circ} \pm 25^{\circ}$. Such a large spin-orbit misalignment, as well

Abstract We have searched for absorption in several common atomic species due to the atmosphere or exosphere of the transiting extrasolar planet HD 209458b, using high precision optical spectra obtained with the Subaru High Dispersion Spectrograph (HDS). Previously we reported an upper limit on $\mathrm{H}\alpha$ absorption of 0.1% ($3 \,\sigma$) within a 5.1 Å band. Using the same procedure, we now report upper limits on absorption due to the optical transitions of Na D, Li, $\mathrm{H}\alpha$,