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Related papers: Photoionization and Opacity

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To investigate the completeness of coupled channel (CC) Breit-Pauli R-Matrix (BPRM) calculations for opacities, we employ the relativistic distorted wave (RDW) method to complement (``top-up'') and compare the BPRM photoionization cross…

Solar and Stellar Astrophysics · Physics 2023-08-30 L. Zhao , S. N. Nahar , W. Eissner , A. K. Pradhan

We derive the photoionisation cross section in dipole approximation for many-electron atoms and ions for neutron star magnetic field strengths in the range of 10^7 to 10^9 T. Both bound and continuum states are treated in adiabatic…

Atomic Physics · Physics 2013-08-08 Thorsten Kersting , Damir Zajec , Peter Diemand , Günter Wunner

We study theoretically the propagation of relatively long pulses with ionizing intensities in a hollow-core photonic crystal fiber filled with a Raman-inactive gas. Due to photoionization, previously unknown types of asymmetric self-phase…

In our recent paper [1], we reported observations of photon blockade by one atom strongly coupled to an optical cavity. In support of these measurements, here we provide an expanded discussion of the general phenomenology of photon blockade…

Quantum Physics · Physics 2009-11-11 K. M. Birnbaum , A. Boca , R. Miller , A. D. Boozer , T. E. Northup , H. J. Kimble

Ionization is critical in the formation and evolution of plasma dynamics; collisional ionization, in particular, is an often overlooked source of electrons when dealing with laser-plasma interactions. Ionization plays a crucial role in…

Plasma Physics · Physics 2026-03-19 Stephen DiIorio , Ricardo Fonseca , Frank Tsung , Benjamin J. Winjum , Alec G. R. Thomas

Absorption and emission spectra of multicharged-ion plasmas contain a huge number of electron configurations and electric-dipolar lines, which can be handled by global methods. However, some transition arrays consist only of a small bunch…

Atomic Physics · Physics 2013-06-28 Jean-Christophe Pain , Franck Gilleron , Quentin Porcherot , Thomas Blenski

We provide a theoretical analysis of Radiative Shocks, defined as supercritical shocks accompanied by an ionization wave in front of the density jump. In particular, we look at the influence of opacity variation with temperature and photon…

Solar and Stellar Astrophysics · Physics 2011-05-10 M. Busquet , M. Klapisch , F. Thais

We study the problem of time-dependent photoionization of low density gaseous nebulae subjected to sudden changes in the intensity of ionizing radiation. To this end, we write a computer code that solves the full time-dependent energy…

High Energy Astrophysical Phenomena · Physics 2015-06-16 J. García , E. E. Elhoussieny , M. A. Bautista , T. R. Kallman

Quantum information protocols often rely on tomographic techniques to determine the state of the system. A popular method of encoding information is on the different paths a photon may take, for example, parallel waveguides in integrated…

Quantum Physics · Physics 2019-06-11 Davor Curic , Lambert Giner , Jeff S. Lundeen

We use orthogonally polarized two-colour (OTC) laser pulses to separate quantum paths in multiphoton ionization of Ar atoms. Our OTC pulses consist of 400~nm and 800~nm light at a relative intensity ratio of 10:1. We find a hitherto…

We consider the excitation dynamics of the two-photon \sts transition in a beam of atomic hydrogen by 243 nm laser radiation. Specifically, we study the impact of ionization damping on the transition line shape, caused by the possibility of…

Photoionization of atoms by high-order harmonics in the presence of a laser may lead to quantum interference from which information about the photoionization dynamics or the light fields can be extracted. Traditionally, this interference…

Light particle-photon mixing in magnetised plasmas plays a vital role in constraining the existence of new physics, especially axions, dark photons, and ultra-high-frequency gravitational waves. Recently, we derived an expression for the…

High Energy Physics - Phenomenology · Physics 2024-07-17 J. I. McDonald , P. Millington

Accurate radiative transfer coefficients (emissivities, absorptivities, and rotativities) are needed for modeling radiation from relativistically hot, magnetized plasmas such as those found in Event Horizon Telescope sources. Here we…

High Energy Astrophysical Phenomena · Physics 2021-11-03 Andrew Marszewski , Ben S. Prather , Abhishek V. Joshi , Alex Pandya , Charles F. Gammie

We give examples showing that two well-known versions of the S-matrix theory, which describes a nonresonant multiphoton ionization of atoms and ions in intense laser fields, lead to qualitatively different results. The latter refer not only…

Atomic Physics · Physics 2015-05-28 J. H. Bauer

A recently introduced method utilizing dimensional continuation is employed to compute the energy loss rate for a non-relativistic particle moving through a highly ionized plasma. No restriction is made on the charge, mass, or speed of this…

Plasma Physics · Physics 2009-11-11 Lowell S. Brown , Dean L. Preston , Robert L. Singleton

We present a complete set of analytic fits to the non-relativistic photoionization cross sections for the ground states of atoms and ions of elements from H through Si, and S, Ar, Ca, and Fe. Near the ionization thresholds, the fits are…

Astrophysics · Physics 2008-11-26 D. A. Verner , G. J. Ferland , K. T. Korista , D. G. Yakovlev

Photoionization models of HII regions require as input a description of the ionizing SED and of the gas distribution, in terms of ionization parameter U and chemical abundances (e.g. O/H and N/O). A strong degeneracy exists between the…

Every observation of astrophysical objects involving a spectrum requires atomic data for the interpretation of line fluxes, line ratios and ionization state of the emitting plasma. One of the processes which determines it is collisional…

High Energy Astrophysical Phenomena · Physics 2017-05-10 I. Urdampilleta , J. S. Kaastra , M. Mehdipour

We describe an approach for incorporating radiative transfer into 3D hydrodynamic cosmological simulations. The method, while approximate, allows for a self-consistent treatment of self-shielding and shadowing, diffuse and point sources of…

Astrophysics · Physics 2007-05-23 Michael L. Norman , Paschalis Paschos , Tom Abel