相关论文: The fundamentals of Lyman-alpha exoplanet transits
Transiting exoplanets provide detailed access to their atmospheres, as the planet's signal can be effectively separated from that of its host star. For transiting exoplanets three fundamental atmospheric measurements are possible:…
Hydrogen Ly-alpha is our primary emission-line window into high redshift galaxies. Surprisingly, despite an extensive literature, Ly-alpha radiative transfer in the most realistic case of a dusty, multi-phase medium has not received…
The transit method is a promising means to detect exomoons, but few candidates have been identified. For planets close to their stars, the dynamical interaction between a satellite's orbit and the star must be important in their evolution.…
Lyman-$\alpha$ (Ly$\alpha$) emitting galaxies are powerful tools to probe the late stages of cosmic reionization. The observed sudden drop in Ly$\alpha$ fraction at $z>6$ is often interpreted as a sign of reionization, since the…
Exoplanets with substantial Hydrogen/Helium atmospheres have been discovered in abundance, many residing extremely close to their parent stars. The extreme irradiation levels these atmospheres experience causes them to undergo hydrodynamic…
Transits in the H I 1216 A (Lyman alpha), O I 1334 A, C II 1335 A, and Si III 1206.5 A lines constrain the properties of the upper atmosphere of HD209458b. In addition to probing the temperature and density profiles in the thermosphere,…
Transit observations of HD209458b in the UV revealed signatures of neutral magnesium escaping the planet's upper atmosphere. The absorption detected in the MgI line provides unprecedented information on the physical conditions at the…
Atmospheric escape is now considered the major contributing factor in shaping the demographic of detected exoplanets. However, inferences about the exoplanet populations strongly depend on the accuracy of the models. Direct observational…
Lyman-alpha line profiles are a powerful probe of ISM structure, outflow speed, and Lyman continuum escape fraction. In this paper, we present the Ly$\alpha$ line profiles of the COS Legacy Archive Spectroscopic SurveY, a sample rich in…
Gas kinematics affect the radiative transfer and escape of hydrogen Lyman-$\alpha$ (Ly$\alpha$) emission from galaxies. We investigate this interplay empirically by relating the ionised gas kinematics of 42 galaxies in the extended…
We constructed a multi-fluid two-dimensional hydrodynamic model with detailed radiative transfer to depict the escape of particles. We found that the tidal forces supply significant accelerations and result in anisotropic winds. An…
The hydrodynamic escape driven by external or internal energy sources sculpts the population of low mass close-in planets. However, distinguishing between the driving mechanisms responsible for the hydrodynamic escape of hydrogen-rich…
The Lyman-$\alpha$ forest refers to the series of absorption features observed in the spectra of distant quasars that are produced by neutral hydrogen in the intergalactic medium. Observed over a wide range of redshifts with both ground-…
One of the current challenges in galaxy evolution studies is to establish the mechanisms that govern the escape of ionizing radiation from galaxies. Here, we investigate the connection between Lyman Continuum (LyC) escape and the conditions…
The most productive tracer of exoplanetary atmospheric escape is the measurement of excess absorption in the near-infrared metastable helium triplet during transits. Atmospheric escape of a close-in planet's atmosphere plays a role in its…
The Lyman continuum (LyC) cannot be observed at the epoch of reionization (z {\gtrsim} 6) due to intergalactic H I absorption. To identify Lyman continuum emitters (LCEs) and infer the fraction of escaping LyC, astronomers have developed…
The significance of the Ly$\alpha$ emission line as a probe of the high-redshift Universe has long been established. Originating mainly in the vicinity of young, massive stars and in association with accretion of large bulks of matter, it…
Absorption of stellar X-ray and Extreme Ultraviolet radiation in the upper atmosphere of close-in exoplanets can give rise to hydrodynamic outflows, which may lead to the gradual shedding of their primordial, light element envelopes. Excess…
To date, more than 750 planets have been discovered orbiting stars other than the Sun. Two sub-classes of these exoplanets, "hot Jupiters" and their less massive counterparts "hot Neptunes," provide a unique opportunity to study the…
We report a quantitative study of the escape of Lyman-alpha photons from an inhomogeneous optically thick medium that mimics the structure of damped Lyman-alpha absorbers. Modeling the optically thick disk with 3 components (massive stars…