We present a thermal emission spectrum of the bloated hot Jupiter HAT-P-32Ab from a single eclipse observation made in spatial scan mode with the Wide Field Camera 3 (WFC3) aboard the Hubble Space ...Telescope (HST). The spectrum covers the wavelength regime from 1.123 to 1.644 mu m which is binned into 14 eclipse depths measured to an averaged precision of 104 parts-per million. The spectrum is unaffected by a dilution from the close M-dwarf companion HAT-P-32B, which was fully resolved. We complemented our spectrum with literature results and performed a comparative forward and retrieval analysis with the 1D radiative-convective ATMO model. Assuming solar abundance of the planet atmosphere, we find that the measured spectrum can best be explained by the spectrum of a blackbody isothermal atmosphere with T-p = 1995 +/- 17 K, but can equally well be described by a spectrum with modest thermal inversion. The retrieved spectrum suggests emission from VO at the WFC3 wavelengths and no evidence of the 1.4 mu m water feature. The emission models with temperature profiles decreasing with height are rejected at a high confidence. An isothermal or inverted spectrum can imply a clear atmosphere with an absorber, a dusty cloud deck or a combination of both. We find that the planet can have continuum of values for the albedo and recirculation, ranging from high albedo and poor recirculation to low albedo and efficient recirculation. Optical spectroscopy of the planet's day-side or thermal emission phase curves can potentially resolve the current albedo with recirculation degeneracy.
We report the discovery and the Rossiter-McLaughlin effect of Kepler-8b, a transiting planet identified by the NASA Kepler Mission. Kepler photometry and Keck-HIRES radial velocities yield the radius ...and mass of the planet around this F8IV subgiant host star. The planet has a radius RP = 1.419 RJ and a mass, MP = 0.60 MJ, yielding a density of 0.26 g cm^-3, among the lowest density planets known. The orbital period is P = 3.523 days and orbital semima jor axis is 0.0483+0.0006/-0.0012 AU. The star has a large rotational v sin i of 10.5 +/- 0.7 km s^-1 and is relatively faint (V = 13.89 mag), both properties deleterious to precise Doppler measurements. The velocities are indeed noisy, with scatter of 30 m s^-1, but exhibit a period and phase consistent with the planet implied by the photometry. We securely detect the Rossiter-McLaughlin effect, confirming the planet's existence and establishing its orbit as prograde. We measure an inclination between the projected planetary orbital axis and the projected stellar rotation axis of lambda = -26.9 +/- 4.6 deg, indicating a moderate inclination of the planetary orbit. Rossiter-McLaughlin measurements of a large sample of transiting planets from Kepler will provide a statistically robust measure of the true distribution of spin-orbit orientations for hot jupiters in general.
HD 3167 is a bright (V = 8.9), nearby KO star observed by the NASA K2 mission (EPIC 220383386), hosting two small, short-period transiting planets. Here we present the results of a multi-site, ...multi-instrument radial-velocity campaign to characterize the HD 3167 system. The masses of the transiting planets are 5.02 +/- 0.38 M-circle plus for HD 3167 b, a hot super-Earth with a likely rocky composition (rho(b) = 5.6(-1.43)(+2.15) g cm(-3)), and 9.80(-1.24)(+1.30) M-circle plus for HD 3167 c, a warm sub-Neptune with a likely substantial volatile complement (rho(c) = 1.97(-0.59)(+0.94) g cm(-3)). We explore the possibility of atmospheric composition analysis and determine that planet c is amenable to transmission spectroscopy measurements, and planet b is a potential thermal emission target. We detect a third, non-transiting planet, HD 3167 d, with a period of 8.509 +/- 0.045 d (between planets b and c) and a minimum mass of 6.90 +/- 0.71 M-circle plus. We are able to constrain the mutual inclination of planet d with planets b and c: we rule out mutual inclinations below 1.degrees 3 because we do not observe transits of planet d. From 1.degrees 3 to 40 degrees, there are viewing geometries invoking special nodal configurations, which result in planet d not transiting some fraction of the time.
We report a spectroscopic orbit with period P = 3.52433 +/- 0.00027 days for
the planetary companion that transits the solar-type star HD209458. For the
metallicity, mass, and radius of the star we ...derive Fe/H = 0.00 +/- 0.02, M =
1.1 +/- 0.1 solar masses, and R = 1.3 +/- 0.1 solar radii. This is based on a
new analysis of the iron lines in our HIRES template spectrum, and also on the
absolute magnitude and color of the star, and uses isochrones from four
different sets of stellar evolution models. Using these values for the stellar
parameters we reanalyze the transit data and derive an orbital inclination of i
= 85.2 +/- 1.4 degrees. For the planet we derive a mass of Mp = 0.69 +/- 0.05
Jupiter masses, a radius of Rp = 1.54 +/- 0.18 Jupiter radii, and a density of
0.23 +/- 0.08 grams per cubic cm.
We report a spectroscopic orbit with period P = 3.52433 +/- 0.00027 days for the planetary companion that transits the solar-type star HD209458. For the metallicity, mass, and radius of the star we ...derive Fe/H = 0.00 +/- 0.02, M = 1.1 +/- 0.1 solar masses, and R = 1.3 +/- 0.1 solar radii. This is based on a new analysis of the iron lines in our HIRES template spectrum, and also on the absolute magnitude and color of the star, and uses isochrones from four different sets of stellar evolution models. Using these values for the stellar parameters we reanalyze the transit data and derive an orbital inclination of i = 85.2 +/- 1.4 degrees. For the planet we derive a mass of Mp = 0.69 +/- 0.05 Jupiter masses, a radius of Rp = 1.54 +/- 0.18 Jupiter radii, and a density of 0.23 +/- 0.08 grams per cubic cm.
