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Results for “evaporation”
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Secondary organic aerosol formation from evaporated biofuels: comparison to gasoline and correction for vapor wall losses
With an ongoing interest in displacing petroleum-based sources of energy with biofuels, we measure and model the formation and composition of secondary organic aerosol (SOA) from organic compounds present in biofuels.
Evaporated organic–MoO 3 composite hole transport layers toward stable perovskite solar cells
The release and diffusion of corrosive iodine species limit perovskite solar cell (PSC) stability. An organic-MoO 3 composite hole transport layer (HTL) with enhanced thermal stability is devised to suppress iodine diffusion and improve PSC stability.
Effects of radiation pressure on the evaporative wind of HD 209458b
ABSTRACT The role of radiation pressure in shaping exoplanet photoevaporation remains a topic of contention. Radiation pressure from the exoplanet’s host star has been proposed as a mechanism to drive the escaping atmosphere into a ‘cometary’ tail and explain the high velocities observed in systems where mass-loss is occurring. In this paper, we present results from high-resolution 3D hydrodynamic simulations of a planet similar to HD 209458b. We self-consistently launch a wind flowing outwards from the planet by calculating the ionization and heating resulting from incident high-energy radiation, and account for radiation pressure. We first present a simplified calculation, setting a limit on the Lyman-α flux required to drive the photoevaporated planetary material to larger radii and line-of-sight velocities. We then present the results of our simulations, which confirm the limits determined by our analytic calculation. We thus demonstrate that, within the limits of our hydrodynamic simulation and for the Lyman-α fluxes expected for HD 209458, radiation pressure is unlikely to significantly affect photoevaporative winds or to explain the high velocities at which wind material is observed, though further possibilities remain to be investigated.
Effects of charge exchange on the evaporative wind of HD 209458b
ABSTRACT The role of charge exchange in shaping exoplanet photoevaporation remains a topic of contention. Exchange of electrons between stellar wind protons from the exoplanet’s host star and neutral hydrogen from the planet’s wind has been proposed as a mechanism to create ‘energetic neutral atoms’ (ENAs), which could explain the high absorption line velocities observed in systems where mass-loss is occurring. In this paper, we present results from three-dimensional hydrodynamic simulations of the mass-loss of a planet similar to HD 209458b. We self-consistently launch a planetary wind by calculating the ionization and heating resulting from incident high-energy radiation, inject a stellar wind into the simulation, and allow electron exchange between the stellar and planetary winds. We predict the potential production of ENAs by the wind–wind interaction analytically, and then present the results of our simulations, which confirm the analytic limits. Within the limits of our hydrodynamic simulation, we find that charge exchange with the stellar wind properties examined here is unable to explain the absorption observed at high Doppler velocities.
Quarkonium polarization in Pb + Pb collisions in the improved color evaporation model
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Level densities for Ga 69 , 71 nuclei using a particle-evaporation technique
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Ensemble from coarse graining: Reconstructing the interior of an evaporating black hole
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Production and polarization of direct J / ψ to O ( α s 3 ) in the improved color evaporation model in collinear factorization
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Primordial black hole evaporation and dark matter production. I. Solely Hawking radiation
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Primordial black hole evaporation and dark matter production. II. Interplay with the freeze-in or freeze-out mechanism
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Extremal Kerr black hole dark matter from Hawking evaporation
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The use of soil moisture and Standardized Evaporative Stress Ratio (SESR) anomalies for increased lead time of the development flash drought and heat waves
Drought and rapid intensification of drought (i.e., flash drought) can have significant impacts on the natural environment and the economy, particularly when coupled with a period(s) of extreme heat (Otkin et al., 2018). The development and/or intensification of drought falls squarely in the sub-seasonal to seasonal (S2S) time frame, which dictates that drought development, intensification, and propagation could be an output of a subseasonal or seasonal forecast. Current S2S forecasts have poor skill for forecasting the development of extreme drought and heat waves.