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Title: 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 cosine-screened 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 positron-hydrogen collisions in dense quantum plasma is the first reported in the literature.

Authors:
 [1];  [1];  [2]
  1. Department of Mathematics, Burdwan University, Golapbag, Burdwan 713 104, West Bengal (India)
  2. (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, E-mail: 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, E-mail: 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, E-mail: 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, E-mail: 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 cosine-screened 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 positron-hydrogen 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 distorted-wave theory in the momentum space. The interactions among the charged particles in the plasma have been represented by Debye-Huckel potentials. Making use of a simple variationally determined wave function for the hydrogen atom, it has been possible to obtain the distorted-wave 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 » 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 1s→nlm inelastic positron-hydrogen collisions for arbitrary n, l, m in weakly coupled plasmas is the first reported in the literature.« less
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