English
Related papers

Related papers: Molecular Hydrogen Formation on Astrophysically Re…

200 papers

The advent of precise measurements of the cosmic microwave background (CMB) anisotropies has motivated correspondingly precise calculations of the cosmic recombination history. Cosmic recombination proceeds far out of equilibrium because of…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Esfandiar Alizadeh , Christopher M. Hirata

The development of molecular complexity during stellar and planetary formation owes much to the interaction of gas and dust. When the first astrochemical models including solid-state chemistry were developed more than forty years ago, data…

Models play an important role in our understanding of the global structure of the solar wind and its interaction with the interstellar medium. A critical ingredient in many types of models are the charge-exchange collisions between ions and…

Solar and Stellar Astrophysics · Physics 2020-06-30 M. Bzowski , J. Heerikhuisen

The widespread use of metallic structures in space technology brings risk of degradation which occurs under space conditions. New types of materials dedicated for space applications, that have been developed in the last decade, are in…

Materials Science · Physics 2015-06-08 Maciej Sznajder , Ulrich Geppert , Mirosław Dudek

We use one-dimensional radiative transfer simulations to study the evolution of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in the primordial universe. We find a new positive feedback mechanism capable of…

Astrophysics · Physics 2009-10-31 Massimo Ricotti , Nickolay Y. Gnedin , J. Michael Shull

We survey the current situation regarding chemical modelling of the synthesis of molecules in the interstellar medium. The present state of knowledge concerning the rate coefficients and their uncertainties for the major gas-phase processes…

Recent laboratory experiments on interstellar dust analogues have shown that H_2 formation on dust grain surfaces is efficient in a range of grain temperatures below 20 K. These results indicate that surface processes may account for the…

Astrophysics · Physics 2009-11-13 Hagai B. Perets , Ofer Biham

Many molecules observed in the interstellar medium are thought to result from thermal desorption of ices. Parameters such as desorption energy and pre-exponential frequency factor are essential to describe the desorption of molecules.…

Astrophysics of Galaxies · Physics 2023-08-16 N. F. W. Ligterink , M. Minissale

The adsorption of hydrogen at nonpolar GaN(1-100) surfaces and its impact on the electronic and vibrational properties is investigated using surface electron spectroscopy in combination with density functional theory (DFT) calculations. For…

Materials Science · Physics 2017-06-28 L. Lymperakis , J. Neugebauer , M. Himmerlich , S. Krischok , M. Rink , J. Kröger , V. M. Polyakov

Using the King & Wells method, we present experimental data on the dependence of the sticking of molecular hydrogen and deuterium on the beam temperature onto non- porous amorphous solid water (ASW) ice surfaces of interstellar interest. A…

Chemical Physics · Physics 2015-05-19 E. Matar , H. Bergeron , F. Dulieu , H. Chaabouni , M. Accolla , J. L. Lemaire

The problem of antiproton scattering on the molecular Hydrogen is investigated by means of wave packet dynamics. The electronically potential energy surfaces of the antiproton H2 system are presented within this work. Excitation and…

Atomic Physics · Physics 2015-09-02 Henrik Stegeby , Markus Kowalewski , Konrad Piszczatowski , Hans O. Karlsson

Context: B[e] supergiants are known to have non-spherical winds, and the existence of disks that are neutral in hydrogen close to their stellar surface has been postulated. A suitable mechanism to produce non-spherical winds seems to be…

Astrophysics · Physics 2009-11-11 Michaela Kraus

We reconsider H2 formation on grain surfaces. We develop a rate equation model which takes into account the presence of both physisorbed and chemisorbed sites on the surface, including quantum mechanical tunnelling and thermal diffusion. In…

Astrophysics · Physics 2009-11-10 S. Cazaux , P. Caselli , A. G. G. M. Tielens , J. Le Bourlot , M. C. Walmsley

Atomic hydrogen (HI) is a critical stepping stone in the gas evolution cycle of the interstellar medium (ISM) of the Milky Way. Hi traces both the cold, premolecular state before star formation and the warm, diffuse ISM before and after…

Astrophysics of Galaxies · Physics 2023-07-18 Naomi M. McClure-Griffiths , Snezana Stanimirovic , Daniel R. Rybarczyk

Ammonia is one of the most widely observed molecules in space, and many observations are able to resolve the hyperfine structure due to the electric quadrupole moment of the nitrogen nucleus. The observed spectra often display anomalies in…

Astrophysics of Galaxies · Physics 2023-09-06 J. Loreau , A. Faure , F. Lique , S. Demes , P. J. Dagdigian

In our recent papers (Kereslidze et all 2019a, 2021) a non-standard quasi-molecular mechanism was suggested and applied to treat the cosmological recombination. It was assumed that in the pre-recombination stage of evolution of the Universe…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-26 Tamaz Kereselidze , Irakli Noselidze

Using molecular dynamics simulations, we predict that the inclusion of nonadiabatic electronic excitations influences the dynamics of preadsorbed hydrogen abstraction from the W(110) surface by hydrogen scattering. The hot-atom…

Star formation, together with the associated chemical and energy feedback, is one of the most important processes in galaxy evolution. The star formation activity in galaxies defines and affects many of their fundamental properties, such as…

Astrophysics of Galaxies · Physics 2025-08-14 Ezequiel Lozano , Cecilia Scannapieco , Sebastian E. Nuza

Understanding how the $\mathrm{H}_2$ molecule is formed under the chemical conditions of the interstellar media (ISM) is critical to the whole chemistry of it. Formation of $\mathrm{H}_2$ in the ISM requires a third body acting as a…

Astrophysics of Galaxies · Physics 2023-07-21 Nicolás F. Barrera , Patricio Fuentealba , Francisco Muñoz , Tatiana Gómez , Carlos Cárdenas

Materials at high pressures and temperatures are of great interest for planetary science and astrophysics, warm dense matter physics, and inertial confinement fusion research. Planetary structure models rely on our understanding of the…

Earth and Planetary Astrophysics · Physics 2020-06-23 Ravit Helled , Guglielmo Mazzola , Ronald Redmer