相关论文: Expanding the inventory of spectral lines used to …
The increase in luminosity with time of a main sequence star eventually can lead to substantial evaporation of the oceans on an orbiting terrestrial planet. Subsequently, the gas phase water in the planet's upper atmosphere can be…
By varying the profiles of stellar extreme ultraviolet (EUV) spectral energy distribution (SED), we tested the influences of stellar EUV SEDs on the physical and chemical properties of the escaping atmosphere. We apply our model to study…
Intense X-ray and ultraviolet stellar irradiation can heat and inflate the atmospheres of closely orbiting exoplanets, driving mass outflows that may be significant enough to evaporate a sizable fraction of the planet atmosphere over the…
We searched for spectral signatures from the exosphere of HD209458 in the UV and the near-IR with UVES and ISAAC at the VLT. We looked in particular for the helium absorption feature at 10 830 \AA predicted to be among the strongest ones.…
Of the over 200 known extrasolar planets, 14 exhibit transits in front of their parent stars as seen from Earth. Spectroscopic observations of the transiting planets can probe the physical conditions of their atmospheres. One such technique…
Ground-based high-resolution spectra provide a powerful tool for characterising exoplanet atmospheres. However, they are greatly hampered by the dominating telluric and stellar lines, which need to be removed prior to any analysis. Such…
Transmission spectroscopy during planetary transits is expected to be a major source of information on the atmospheres of small (approximately Earth-sized) exoplanets in the next two decades. This technique, however, is intrinsically…
Identifying Earth-like planets outside out solar system is a leading research goal in astronomy, but determining if candidate planets have atmospheres, and more importantly if they can retain atmospheres, is still out of reach. In this…
One of the great quests of astronomy is to obtain the spectrum of a terrestrial planet orbiting within the habitable zone of its star, and the dominant challenge in doing so is to isolate the light of the planet from that of the star.…
The conventional observables to identify a habitable or inhabited environment in exoplanets, such as an ocean glint or abundant atmospheric O$_2$, will be challenging to detect with present or upcoming observatories. Here we suggest a new…
Atmospheric escape is considered to be one of the main channels for evolution in sub-Jovian planets, particularly in their early lives. While there are several hypotheses proposed to explain escape in exoplanets, testing them with…
Over the course of the past decade, advances in the radial velocity and transit techniques have enabled the detection of rocky exoplanets in the habitable zones of nearby stars. Future observations with novel methods are required to…
What makes the study of exoplanetary atmospheres so hard is the extraction of its tiny signal from observations, usually dominated by telluric absorption, stellar spectrum and instrumental noise. The High Resolution Spectroscopy has emerged…
The physical characteristics and atmospheric chemical composition of newly discovered exoplanets are often inferred from their transit spectra which are obtained from complex numerical models of radiative transfer. Alternatively, simple…
In recent years, high-resolution transmission spectroscopy in the near-infrared has led to detections of prominent molecules in several giant exoplanets on close-in orbits. This approach has traditionally relied on the large Doppler shifts…
Accurately determining escape rates from a planet's atmosphere is critical for determining its evolution. Escape can be driven by upward thermal conduction of energy deposited well below the exobase, as well as by non-thermal processes…
The majority of exoplanets found to date have been discovered via the transit method, and transmission spectroscopy represents the primary method of studying these distant worlds. Currently, in-depth atmospheric characterization of…
We use thermodynamic calculations to model atmospheric chemistry on terrestrial exoplanets that are hot enough for chemical equilibira between the atmosphere and lithosphere, as on Venus. The results of our calculations place constraints on…
The metastable helium line at 1083 nm can be used to probe the extended upper atmospheres of close-in exoplanets and thus provide insight into their atmospheric mass loss, which is likely to be significant in sculpting their population. We…
One of the frontier research fields of exoplanetary science is the study of the composition and variability of exoplanetary atmospheres. This field is now moving from the gas giant planets towards the smaller and colder telluric planets,…