Related papers: Generic Models for Disk-Resolved and Disk-Integrat…
We point out some advantages of making observations of extrasolar planets in linearly polarized (LP) light. Older cool stars have quite low levels (~ 10^-4 to 10^-5) of fractional LP, while extrasolar planets can have relatively high…
The X-ray spectra of accreting stellar-mass black hole systems exhibit spectral features due to reflection, especially broad iron K alpha emission lines. We investigate the reflection by the accretion disc that can be expected in the…
High-accuracy multicolor light curves of the binary system HD 189733, which contains an exoplanet, are analyzed. We have determined the radii of the star and the planet in the binary system, as well as the orbital inclination. The…
Modeling based on differentiable programming holds great promise for astronomy, enabling advanced techniques such as gradient-based posterior sampling and optimization. This paradigm motivated us to develop ExoJAX (Kawahara et al. 2022),…
Atmospheric heat redistribution shapes the remote appearance of rocky exoplanets but there is currently no easy way to predict a planet's heat redistribution from its physical properties. This paper proposes an analytical scaling theory for…
We report the results of a ${\sim}4$-year direct imaging survey of 104 stars to resolve and characterize circumstellar debris disks in scattered light as part of the Gemini Planet Imager Exoplanet Survey. We targeted nearby (${\lesssim}150$…
Giant exoplanets located >1 AU away from their parent stars have atmospheric environments cold enough for water and/or ammonia clouds. We have developed a new equilibrium cloud and reflected light spectrum model, ExoREL, for widely…
The characterization of planetary atmospheres is a daunting task, pushing current observing facilities to their limits. The next generation of high-resolution spectrographs mounted on large telescopes -- such as ESPRESSO@VLT and HIRES@ELT…
Clouds have an important role in the atmospheres of planetary bodies. It is expected that, like all the planetary bodies in our solar system, exoplanet atmospheres will also have substantial cloud coverage, and evidence is mounting for…
We employ a two-dimensional grid-based hydrodynamic model to simulate upper atmospheric dynamics on extrasolar giant planets. Our model is well-suited to simulate the dynamics of the atmospheres of planets with high orbital eccentricity…
We model the IR Spectral Energy Distribution of circumstellar disks embedded in a HII region and photoevaporated by the external UV radiation. The model applies to the photoevaporated disks (proplyds) in Orion Nebula. First we calculate the…
We present an analysis on the detection viability of refraction effects in Kepler's exoplanet atmospheres using binning techniques for their light curves in order to compare against simulated refraction effects. We split the Kepler…
We discuss a model of an X-ray illuminating source above an accretion disk of a rotating black hole. Within the so called lamp-post scheme we compute the expected (observed) polarization properties of the radiation reaching an observer. We…
We present our analysis of the red-channel CoRoT data of CoRoT-2b. A deep secondary eclipse is detected at a level of 1.02+-0.20 x10-4, which suggests that all of the planet-signal detected previously in white light by Alonso et al. (2009)…
We investigate the intrinsic continuum linear polarization from axisymmetric density distributions of gas surrounding classical Be stars during the formation and dissipation of their circumstellar disks. We implement a Monte Carlo…
Motivated by the success of the IXPE mission, we elucidate what can be inferred about 3D matter structures forming about the equatorial plane of accreting compact objects from 0.1-100 keV linear polarization induced by non-relativistic…
We investigate high resolution imaging polarimetry of HD 169142 taken in the R' and I' bands with the SPHERE/ZIMPOL instrument for an accurate quantitative measurement of the radiation scattered by the circumstellar disk. We observe a…
Some extrasolar giant planets in close orbits---"hot Jupiters"---exhibit larger radii than that of a passively cooling planet. The extreme irradiation $L_{\rm eq}$ these hot Jupiters receive from their close in stars creates a thick…
Unlike previously explored relationships between the properties of hot Jovian atmospheres, the geometric albedo and the incident stellar flux do not exhibit a clear correlation, as revealed by our re-analysis of Q0 to Q14 Kepler data. If…
Since in situ studies and interplanetary dust collections only provide a spatially limited amount of information about the interplanetary dust properties, it is of major importance to complete these studies with properties inferred from…