Related papers: Ca II H&K stellar activity parameter: a proxy for …
Extreme ultraviolet (EUV) radiations (10--117 nm) from host stars play important roles in the ionization, heating, and mass loss from exoplanet atmospheres. Together with the host star's Lyman-alpha and far-UV (117--170 nm) radiation, EUV…
Correct estimates of stellar extreme ultraviolet (EUV; 100 - 1170 \AA) flux are important for studying the photochemistry and stability of exoplanet atmospheres, as EUV radiation ionizes hydrogen and contributes to the heating, expansion,…
Atmospheric escape is an important process that controls the long-term evolution of close-in planets. We perform radiation hydrodynamics simulations of photo-evaporation of exoplanets' atmospheres to study the effect of photoelectric…
Much of the focus of exoplanet atmosphere analysis in the coming decade will be at infrared wavelengths, with the planned launches of the James Webb Space Telescope (JWST) and the Wide-Field Infrared Survey Telescope (WFIRST). However,…
Exoplanet atmospheres are known to be vulnerable to mass loss through irradiation by stellar X-ray and extreme-ultraviolet emission. We investigate how this high-energy irradiation varies with time by combining an empirical relation…
M dwarf stars are excellent candidates around which to search for exoplanets, including temperate, Earth-sized planets. To evaluate the photochemistry of the planetary atmosphere, it is essential to characterize the UV spectral energy…
The extreme-ultraviolet (EUV; 100 -- 911 \AA) spectra of F, G, K, and M stars provide diagnostics of the stellar chromosphere through the corona, with line and continuum formation temperatures spanning roughly 10$^{4}$ - 10$^{7}$ K. The EUV…
Stellar ultraviolet (UV) emission serves as a crucial indicator for estimating magnetic activity and evaluating the habitability of exoplanets orbiting stars. In this paper, we present a straightforward method to derive stellar photospheric…
The spectral energy distribution, variability and evolution of the high-energy radiation from an M dwarf planet host is crucial in understanding the planet's atmospheric evolution and habitability and in interpreting the planet's spectrum.…
The planetary effective surface temperature alone is insufficient to characterize exoplanet atmospheres and their stability or evolution. Considering the star-planet system as a whole is necessary, and a critical component of the system is…
The ultraviolet (UV) light from a host star influences a planet's atmospheric photochemistry and will affect interpretations of exoplanetary spectra from future missions like the James Webb Space Telescope. These effects will be…
Extreme Ultraviolet (EUV) driven atmospheric escape is a key process in the atmospheric evolution of close-in exoplanets. In many evolutionary models, the energy-limited mass-loss rate with a constant efficiency (typically $\sim10\%$) is…
Quantifying the evolution of stellar extreme ultraviolet (EUV, 100 -- 1000 $\overset{\circ}{A}$) emission is critical for assessing the evolution of planetary atmospheres and the habitability of M dwarf systems. Previous studies from the…
The X-rays and Extreme Ultraviolet (XUV) emission from M stars can drive the atmospheric escape on planets orbiting them. M stars are also known for their frequent emission of stellar flares, which will increase the high-energy flux…
Upper atmospheres of Hot Jupiters are subject to extreme radiation conditions that can result in rapid atmospheric escape. The composition and structure of the upper atmospheres of these planets are affected by the high-energy spectrum of…
Stellar radiation from X-rays to the visible provides the energy that controls the photochemistry and mass loss from exoplanet atmospheres. The important extreme ultraviolet (EUV) region (10--91.2~nm) is inaccessible and should be computed…
We present a survey of far-ultraviolet (FUV; 1150 - 1450 Ang) emission line spectra from 71 planet-hosting and 33 non-planet-hosting F, G, K, and M dwarfs with the goals of characterizing their range of FUV activity levels, calibrating the…
Kepler Space Telescope and Transiting Exoplanet Survey Satellite unveiled that Sun-like stars frequently host exoplanets. These exoplanets are subject to fluxes of ionizing radiation in the form of X-ray and extreme-ultraviolet (EUV)…
Stellar high-energy radiation (X-ray and extreme ultraviolet, XUV) drives atmospheric escape in close-in exoplanets. Given that stellar irradiation depends on the stellar magnetism and that stars have magnetic cycles, we investigate how…
Far ultraviolet (FUV) emission lines from dwarf stars are important driving sources of photochemistry in planetary atmospheres. Properly interpreting spectral features of planetary atmospheres critically depends on the emission of its host…