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Related papers: Dynamic Hydrogen Ionization

200 papers

We give an updated overview of both weak and strong coupling methods to describe the approach to a plasma described by viscous hydrodynamics, a process now called hydrodynamisation. At weak coupling the very first moments after a heavy ion…

Nuclear Theory · Physics 2017-10-31 Wilke van der Schee

The recent EDGES measurements of the global 21-cm signal from the cosmic dawn suggest that the kinetic temperature of the inter-galactic medium (IGM) might be significantly lower compared to its expected value. The colder IGM directly…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-02 Kanan K. Datta , Aritra Kundu , Ankit Paul , Ankita Bera

We explore a mechanism, entirely new to the fast solar wind, of electron heating by lower hybrid waves to explain the shift to higher charge states observed in various elements in the fast wind at 1 A.U. relative to the original coronal…

Astrophysics · Physics 2009-11-10 J. Martin Laming

Variation of voltage profiles with different time scales leads to the redistribution of deposited energy as well as electro-hydrodynamic forces, while the mechanism and scaling law is still unknown. On the basis of theoretical and numerical…

Plasma Physics · Physics 2020-12-02 Yifei Zhu , Yun Wu

Solar photosphere and chromosphere are composed of weakly ionized plasma for which collisional coupling decreases with height. This implies a breakdown of some hypotheses underlying magnetohydrodynamics at low altitudes and gives rise to…

Solar and Stellar Astrophysics · Physics 2016-11-21 Elena Khomenko

The ionizing background determines the ionization balance and the thermodynamics of the cosmic gas. It is therefore a fundamental ingredient to theoretical and empirical studies of both the IGM and galaxy formation. We present here a new…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-28 C. -A. Faucher-Giguere , A. Lidz , M. Zaldarriaga , L. Hernquist

Many large scale numerical simulations of astrophysical plasmas must also reproduce the hydrogen ionization and the resulting emission spectrum, in some cases quite accurately. We describe a compact model hydrogen atom that can be readily…

Astrophysics · Physics 2009-10-28 Jason W. Ferguson , Gary J. Ferland

We study the ionization process involving antiproton and hydrogen in the energy range between 0.1 keV to 500 keV, using single center close coupling approximation. We construct the scattering wave function using B-spline bases. The results…

Atomic Physics · Physics 2007-05-23 S Sahoo , S C Mukherjee , H R J Walters

The spin temperature of neutral hydrogen, which determines the 21 cm optical depth and brightness temperature, is set by the competition between radiative and collisional processes. In the high-redshift intergalactic medium, the dominant…

Astrophysics · Physics 2008-11-26 Steven Furlanetto , Michael Furlanetto

Direct observations of solar wind are mostly limited to the vicinity of the ecliptic plane. Retrieving the latitudinal structure of solar wind indirectly based on observations of the backscatter glow of interstellar neutral hydrogen is…

Solar and Stellar Astrophysics · Physics 2024-02-14 Izabela Kowalska-Leszczynska , Marzena A. Kubiak , Maciej Bzowski , Marek Strumik

A development of perturbations of number densities of ions and electrons during recombination epoch is analysed. The equations for relative perturbations of ionization fractions were derived from the system of equations for accurate…

Astrophysics · Physics 2009-11-11 B. Novosyadlyj

Recent observations of ultra-hot Jupiters with dayside temperatures in excess of $2500~\mathrm{K}$ have found evidence for new physical processes at play in their atmospheres. In this work, we investigate the effects of the dissociation of…

Earth and Planetary Astrophysics · Physics 2020-01-08 Xianyu Tan , Thaddeus D. Komacek

The history of the transition from a neutral intergalactic medium to one that is almost fully ionized can reveal the character of cosmological ionizing sources. In this talk I will discuss the implications for rival reionization scenarios…

Astrophysics · Physics 2007-05-23 Piero Madau

The critical star formation rate density required to keep the intergalactic hydrogen ionised depends crucially on the average rate of recombinations in the intergalactic medium (IGM). This rate is proportional to the clumping factor C =…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-22 Andreas H. Pawlik , Joop Schaye , Eveline van Scherpenzeel

In this contribution we present the first numerical simulations of a relativistic outflow propagating through the inner hundreds of parsecs of its host galaxy, including atomic and ionised hydrogen, and the cooling effects of ionisation.…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Manel Perucho , José López-Miralles , Victoria Reynaldi , Álvaro Labiano

We have studied the effect of time-dependent ionization and recombination processes on magnetic reconnection in the solar corona. Petschek-type steady reconnection, in which model the magnetic energy is mainly converted at the slow-mode…

Solar and Stellar Astrophysics · Physics 2015-05-30 S. Imada , I. Murakami , T. Watanabe , H. Hara , T. Shimizu

The intergalactic medium (IGM) prior to the epoch of reionization consists mostly of neutral hydrogen gas. Ly-alpha photons produced by early stars resonantly scatter off hydrogen atoms, causing energy exchange between the radiation field…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Antonija Oklopcic , Christopher M. Hirata

Recent observations and theoretical investigations of neutron stars indicate that their atmospheres consist not of hydrogen or iron but possibly other elements such as helium. We calculate the ionization and dissociation equilibrium of…

Astrophysics · Physics 2008-11-26 Kaya Mori , Jeremy S. Heyl

Strong field ionization provides a unique mean to address complex dynamics of an electron in competing Coulomb and laser fields. Recent streak camera experiment (K\"ubel, et al., Phys. Rev. Lett. 119, 183201) analyzed asymmetries in the…

Photoionized and electronically excited ethylene \ce{C2H4+} can undergo \ce{H}-loss, \ce{H2}-loss, and ethylene-ethylidene isomerization, where the latter entails a hydrogen migration. Recent pioneering experiments with few-femtosecond…

Chemical Physics · Physics 2024-05-28 Lina Fransén , Thierry Tran , Saikat Nandi , Morgane Vacher