English
Related papers

Related papers: Radiative processes as diagnostics of cometary atm…

200 papers

Ice naturally forms in the disordered or ``amorphous'' state when accreted from vapor at temperatures and pressures found in the interstellar medium and in the frigid, low density outer regions of the Sun's protoplanetary disk. It is…

Earth and Planetary Astrophysics · Physics 2022-09-14 Dina Prialnik , David Jewitt

Recent advances in the X-ray and soft gamma-ray observations of accreting black holes and microquasars, in particular, are reviewed. The radiative processes responsible for the emission are discussed briefly. The hybrid thermal/nonthermal…

Astrophysics · Physics 2007-05-23 Juri Poutanen , Andrzej A. Zdziarski

As comets journey into the inner solar system, they deliver particulates and volatile gases into their comae that reveal the most primitive materials in the solar system. Cometary dust particles provide crucial information for assessing the…

Earth and Planetary Astrophysics · Physics 2023-09-28 David E. Harker , Diane H. Wooden , Michael S. P. Kelley , Charles E. Woodward

We discuss the different physical processes that are important to understand the thermal X-ray emission and absorption spectra of the diffuse gas in clusters of galaxies and the warm-hot intergalactic medium. The ionisation balance, line…

Astrophysics · Physics 2009-11-13 J. S. Kaastra , F. B. S. Paerels , F. Durret , S. Schindler , P. Richter

We study particle decay as the origin of dark radiation. After elaborating general properties and useful parametrisations we provide model-independent and easy-to-use constraints from nucleosynthesis, the cosmic microwave background and…

High Energy Physics - Phenomenology · Physics 2014-02-14 Jasper Hasenkamp , Jörn Kersten

We consider first-order phase transitions of the Universe in the radiation-dominated era. We argue that in general the velocity of interfaces is non-relativistic due to the interaction with the plasma and the release of latent heat. We…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ariel Megevand

Although transit spectroscopy is a powerful method for studying the composition, thermal properties and dynamics of exoplanet atmospheres, only a few transiting terrestrial exoplanets will be close enough to allow significant transit…

Earth and Planetary Astrophysics · Physics 2015-05-28 Franck Selsis , Robin Wordsworth , François Forget

A cold dilute atomic gas in an optical resonator can be radiatively cooled by coherent scattering processes when the driving laser frequency is tuned close but below the cavity resonance. When sufficiently illuminated, moreover, the atoms'…

Comets hold answers to mysteries of the Solar System by recording presolar history, the initial states of planet formation and prebiotic organics and volatiles to the early Earth. Analysis of returned samples from a comet nucleus will…

A decade of X-ray stellar observations with Chandra and XMM-Newton has led to significant advances in our understanding of the physical processes at work in hot (magnetized) plasmas in stars and their immediate environment, providing new…

Solar and Stellar Astrophysics · Physics 2010-08-26 Paola Testa

An exact model is proposed for a gray, isotropically scattering planetary atmosphere in radiative equilibrium. The slab is illuminated on one side by a collimated beam and is bounded on the other side by an emitting and partially reflecting…

Astrophysics · Physics 2009-11-11 Loic Chevallier , Joachim Pelkowski , Bernard Rutily

This paper is the result of the International Cometary Workshop, held in Toulouse, France in April 2014, where the participants came together to assess our knowledge of comets prior to the ESA Rosetta Mission. In this paper, we look at the…

Rigorous statistical numerical analysis of the response of a nonspherical dust particle ensemble composed of aggregates of astronomical silicate is presented. It is found that the rotational disruption mechanism is not only likely to occur…

Earth and Planetary Astrophysics · Physics 2020-04-23 Joonas Herranen

Radioactive decay of unstable atomic nuclei leads to liberation of nuclear binding energy in the forms of gamma-ray photons and secondary particles (electrons, positrons); their energy then energises surrounding matter. Unstable nuclei are…

High Energy Astrophysical Phenomena · Physics 2023-04-05 Roland Diehl

The physics of energetic particle propagation in magnetised environments plays a crucial role in both the processes of acceleration and transport of cosmic rays. Recent theoretical developments in the field of cosmic ray research have been…

High Energy Astrophysical Phenomena · Physics 2018-10-31 Elena Amato , Pasquale Blasi

Evidence for exocomets, icy bodies in extrasolar planetary systems, has rapidly increased over the past decade. Volatiles are detected through the gas that exocomets release as they collide and grind down within their natal belts, or as…

Comets are a remarkable feature in our night sky, visible on their passage through the inner Solar system as the Sun's energy sublimates ices and liberates surface material, generating beautiful comae, dust, and ion tails. Comets are also…

Earth and Planetary Astrophysics · Physics 2018-06-13 Grant M. Kennedy

Solar and heliospheric cosmic rays provide a unique perspective in cosmic ray research: we can observe not only the particles, but also the properties of the plasmas in which the they are accelerated and propagate, using in situ and…

Space Physics · Physics 2017-02-20 T. Laitinen

Every second millions of small meteoroids enter the Earth's atmosphere producing dense plasmas. Radars easily detect these plasmas and researchers use this data to characterize both the meteoroids and the atmosphere. This paper develops a…

Plasma Physics · Physics 2017-05-24 Y. S. Dimant , M. M. Oppenheim

Climate transitions on exoplanets offer valuable insights into the atmospheric processes governing planetary habitability. Previous pure-steam atmospheric models show a thermal limit in outgoing long-wave radiation, which has been used to…

Earth and Planetary Astrophysics · Physics 2025-05-19 Iris D. Boer , Harrison Nicholls , Tim Lichtenberg