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Related papers: Laboratory Photoionization Fronts in Nitrogen Gas:…

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Measurements of the intergalactic medium (IGM) temperature provide a potentially powerful constraint on the reionisation history due to the thermal imprint left by the photo-ionisation of neutral hydrogen. However, until recently IGM…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Sudhir Raskutti , James S. Bolton , J. Stuart B. Wyithe , George D. Becker

Theoretically self-consistent calculations for photoionization and (e + ion) recombination are described. An identical eigenfunction expansion for the ion is employed in coupled channel calculations for both processes, thus ensuring…

Astrophysics · Physics 2007-05-23 Sultana N. Nahar

In this contribution, we study situations in which nanoparticles in a fluid are strongly heated, generating high heat fluxes. This situation is relevant to experiments in which a fluid is locally heated using selective absorption of…

Materials Science · Physics 2009-11-16 Samy Merabia , Serguei Shenogin , Laurent Joly , Pawel Keblinski , J. -L. Barrat

Photocatalytic nitrogen fixation is an important pathway for carbon neutralization and sustainable development. Inspired by nitrogenase, the participation of molybdenum can effectively activate nitrogen. A novel Ti/Mo composites…

Nitrate ion spikes in polar ice cores are contentiously used to estimate the intensity, frequency, and probability of historical solar proton events, quantities that are needed to prepare for potentially society-crippling space weather…

We extend the recently developed formalism to extract light-front quark charge densities from nucleon form factor data to the deformations of these quark charge densities when applying an external electric field. We show that the resulting…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Gorchtein , C. Lorcé , B. Pasquini , M. Vanderhaeghen

We develop a numerical solver for radiative transfer problems based on the weighted essentially nonoscillatory (WENO) scheme modified with anti-diffusive flux corrections, in order to solve the temperature and ionization profiles around a…

Astrophysics · Physics 2008-11-26 Jing-Mei Qiu , Long-Long Feng , Chi-Wang Shu , Li-Zhi Fang

Radiative cooling is central to a wide range of astrophysical problems. Despite its importance, cooling rates are generally computed using very restrictive assumptions, such as collisional ionization equilibrium and solar relative…

Astrophysics · Physics 2009-01-26 Robert P. C. Wiersma , Joop Schaye , Britton D. Smith

The photoionization model of narrow-line regions (NLRs) in active galactic nuclei (AGNs) has been investigated for decades. Many published models are restricted to simple linear scaling abundance relations, dust-free assumption, uniform AGN…

Astrophysics of Galaxies · Physics 2023-05-23 Peixin Zhu , Lisa J. Kewley , Ralph S. Sutherland

In photoionized gases with cosmic abundances, dielectronic recombination (DR) proceeds primarily via nlj --> nl'j' core excitations (Dn=0 DR). We have measured the resonance strengths and energies for Fe XVIII to Fe XVII and Fe XIX to Fe…

We photoionize nitrogen molecules with a train of extreme ultraviolet attosecond pulses together with a weak infrared field. We measure the phase of the two-color two-photon ionization transition (molecular phase) for different states of…

Observational studies indicate that the intergalactic medium (IGM) is highly ionized up to redshifts just over 6. A number of models have been developed to describe the process of reionization and the effects of the ionizing photons from…

Astrophysics · Physics 2009-11-07 Aparna Venkatesan , Mark L. Giroux , J. Michael Shull

Early results from JWST suggest that epoch-of-reionization (EoR) galaxies produce copious ionizing photons, which, if they escape efficiently, could cause reionization to occur too early. We study this problem using \jwst\ imaging and prism…

High-resolution photoionization experiments were carried out using beams of Be-like C$^{2+}$, N$^{3+}$, and O$^{4+}$ ions with roughly equal populations of the $^1$S ground-state and the $^3$P$^o$ manifold of metastable components. The…

Earth and Planetary Astrophysics · Physics 2012-03-30 A Müller , S Schippers , R. A. Phaneuf , A. L. D. Kilcoyne , H. Bräuning , A. S. Schlachter , M. Lu , B. M. McLaughlin

We have employed the VULCAN laser facility to generate a laser plasma X-ray source for use in photoionisation experiments. A nanosecond laser pulse with an intensity of order ${10}^{15}$ W{cm}$^{-2}$ was used to irradiate thin Ag or Sn foil…

Negative ions have been detected in abundance in recent years by spacecraft across the solar system. These detections were, however, made by instruments not designed for this purpose and, as such, significant uncertainties remain regarding…

Space Physics · Physics 2021-06-17 Ravindra T. Desai , Zeqi Zhang , Xinni Wu , Charles Lue

We examine the incidence of cold fronts in a large sample of galaxy clusters extracted from a (512h^-1 Mpc) hydrodynamic/N-body cosmological simulation with adiabatic gas physics computed with the Enzo adaptive mesh refinement code. This…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Eric J. Hallman , Samuel W. Skillman , Tesla E. Jeltema , Britton D. Smith , Brian W. O'Shea , Jack O. Burns , Michael L. Norman

We have modelled the process of reionization of the IGM by photoionization by galaxies, in order to predict the epoch of reionization. We use a sophisticated semi-analytic model to track the formation of galaxies. Our study represents a…

Astrophysics · Physics 2009-11-11 A. J. Benson , Naoshi Sugiyama , Adi Nusser , C. G. Lacey

We compute the production of thermal photons in relativistic heavy-ion collisions by gluon fusion in the presence of an intense magnetic field, and during the early stages of the reaction. This photon yield is an excess over calculations…

High Energy Physics - Phenomenology · Physics 2017-04-20 Alejandro Ayala , Jorge David Castano-Yepes , C. A. Dominguez , L. A. Hernandez

In a semi-numerical model of reionization, the evolution of ionization fraction is simulated approximately by the ionizing photon to baryon ratio criterion. In this paper we incorporate a semi-analytical model of galaxy formation based on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jie Zhou , Qi Guo , Gaochao Liu , Bin Yue , Yidong Xu , Xuelei Chen
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