Positron impact excitations of hydrogen atom embedded in dense quantum plasmas: Formation of Rydberg atoms
Abstract
Formation of Rydberg atoms due to 1 s → nlm excitations of hydrogen by positron impact, for arbitrary n, l, m, in dense quantum plasma has been investigated using a distorted wave theory which includes screened dipole polarization potential. The interactions among the charged particles in the plasma have been represented by exponential cosinescreened Coulomb potentials. Making use of a simple variationally determined hydrogen wave function, it has been possible to obtain the distorted wave scattering amplitude in a closed analytical form. A detailed study has been made to explore the structure of differential and total cross sections in the energy range 20–300 eV of incident positron. For the unscreened case, our results agree nicely with some of the most accurate results available in the literature. To the best of our knowledge, such a study on the differential and total cross sections for 1 s → nlm inelastic positronhydrogen collisions in dense quantum plasma is the first reported in the literature.
 Authors:
 Department of Mathematics, Burdwan University, Golapbag, Burdwan 713 104, West Bengal (India)
 (India)
 Publication Date:
 OSTI Identifier:
 22403299
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ATOMS; DISTORTED WAVE THEORY; EXCITATION; HYDROGEN; POSITRONS; QUANTUM PLASMA; SCATTERING AMPLITUDES; TOTAL CROSS SECTIONS
Citation Formats
Rej, Pramit, Ghoshal, Arijit, Email: arijit98@yahoo.com, and Department of Mathematics, Kazi Nazrul University, B C W Campus, Asansol 713 304, West Bengal. Positron impact excitations of hydrogen atom embedded in dense quantum plasmas: Formation of Rydberg atoms. United States: N. p., 2014.
Web. doi:10.1063/1.4901916.
Rej, Pramit, Ghoshal, Arijit, Email: arijit98@yahoo.com, & Department of Mathematics, Kazi Nazrul University, B C W Campus, Asansol 713 304, West Bengal. Positron impact excitations of hydrogen atom embedded in dense quantum plasmas: Formation of Rydberg atoms. United States. doi:10.1063/1.4901916.
Rej, Pramit, Ghoshal, Arijit, Email: arijit98@yahoo.com, and Department of Mathematics, Kazi Nazrul University, B C W Campus, Asansol 713 304, West Bengal. 2014.
"Positron impact excitations of hydrogen atom embedded in dense quantum plasmas: Formation of Rydberg atoms". United States.
doi:10.1063/1.4901916.
@article{osti_22403299,
title = {Positron impact excitations of hydrogen atom embedded in dense quantum plasmas: Formation of Rydberg atoms},
author = {Rej, Pramit and Ghoshal, Arijit, Email: arijit98@yahoo.com and Department of Mathematics, Kazi Nazrul University, B C W Campus, Asansol 713 304, West Bengal},
abstractNote = {Formation of Rydberg atoms due to 1 s → nlm excitations of hydrogen by positron impact, for arbitrary n, l, m, in dense quantum plasma has been investigated using a distorted wave theory which includes screened dipole polarization potential. The interactions among the charged particles in the plasma have been represented by exponential cosinescreened Coulomb potentials. Making use of a simple variationally determined hydrogen wave function, it has been possible to obtain the distorted wave scattering amplitude in a closed analytical form. A detailed study has been made to explore the structure of differential and total cross sections in the energy range 20–300 eV of incident positron. For the unscreened case, our results agree nicely with some of the most accurate results available in the literature. To the best of our knowledge, such a study on the differential and total cross sections for 1 s → nlm inelastic positronhydrogen collisions in dense quantum plasma is the first reported in the literature.},
doi = {10.1063/1.4901916},
journal = {Physics of Plasmas},
number = 11,
volume = 21,
place = {United States},
year = 2014,
month =
}

Formation of Rydberg atoms due to 1s→nlm excitations of hydrogen, for arbitrary n, l, m, by positron impact in weakly coupled plasma has been investigated using a distortedwave theory in the momentum space. The interactions among the charged particles in the plasma have been represented by DebyeHuckel potentials. Making use of a simple variationally determined wave function for the hydrogen atom, it has been possible to obtain the distortedwave scattering amplitude in a closed analytical form. A detailed study has been made on the effects of plasma screening on the differential and total cross sections in the energy range 20–300 eVmore »

Positron scattering from hydrogen atom embedded in dense quantum plasma
Scattering of positrons from the ground state of hydrogen atoms embedded in dense quantum plasma has been investigated by applying a formulation of the threebody collision problem in the form of coupled multichannel twobody LippmannSchwinger equations. The interactions among the charged particles in dense quantum plasma have been represented by exponential cosinescreened Coulomb potentials. Variationally determined hydrogenic wave function has been employed to calculate the partialwave scattering amplitude. Plasma screening effects on various possible mode of fragmentation of the system e{sup +}+H(1s) during the collision, such as 1s→1s and 2s→2s elastic collisions, 1s→2s excitation, positronium formation, elastic protonpositronium collisions, havemore » 
Ratios of doubletosingle photoionization cross sections of helium atom embedded in dense quantum plasmas at high nonrelativistic photon energies
An investigation on the asymptotic ratios of doubletosingle photoionization cross sections of the helium atom (He) embedded in dense quantum plasmas at very high nonrelativistic photon energies has been made. Exponential cosinescreened Coulomb potential has been used to represent the effective potential of a test charge in a dense quantum plasma. Making use of highly correlated wave functions for the ground states of He, results of the asymptotic ratios (R) of doubletosingle photoionization cross sections for the screening parameter in the range [0,0.5] a.u. are reported. The reported value of R for the unscreened case confirms its established value. Amore » 
Dynamics of positronium formation in positronhydrogen collisions embedded in weakly coupled plasmas
Dynamics of positronium (Ps) formation in an arbitrary sstate from an arbitrary sstate of the hydrogen atom in weakly coupled plasma has been investigated within the framework of a distortedwave theory. The interactions among the charged particles in the plasma have been represented by DebyeHuckel potentials. Using simple variational hydrogenic wave functions and arbitrary order derivatives of the general threedenominator Lewis integral partialwave scattering amplitudes have been obtained in closed forms. These distortedwave scattering amplitudes have been used to make a detailed study on differential and total cross sections. It has been found that screening of the interaction potentials hasmore » 
Resonances in positronhydrogen scattering in dense quantum plasmas
We have investigated the Swave resonance states in positronhydrogen system embedded in dense quantum plasmas using Hylleraastype wave functions within the framework of the stabilization method. The effect of quantum plasmas has been incorporated using the exponentialcosinescreened Coulomb (modified Yukawatype) potential. Resonance parameters (both position and width) below the Ps n = 2 threshold are reported as functions of plasma screening parameters.