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Title: New longitudinal mode and compression of pair ions in plasma

Abstract

Positive and negative ions forming the so-called pair plasma differing in sign of their charge but asymmetric in mass and temperature support a new acoustic-like mode. The condition for the excitation of ion sound wave through electron beam induced Cherenkov instability is also investigated. This beam can generate a perturbation in the pair ion plasmas in the presence of electrons when there is number density, temperature, and mass difference in the two species of ions. Basic emphasis is on the focusing of ion sound waves, and we show how, in the area of localization of wave energy, the density of pair particles increases while electrons are pushed away from that region. Further, this localization of wave is dependent on the shape of the pulse. Considering the example of pancake and bullet shaped pulses, we find that only the former leads to compression of pair ions in the supersonic regime of the focusing region. Here, possible existence of regions where pure pair particles can exist may also be speculated which is not only useful from academic point of view but also to mimic the situation of plasma (electron positron asymmetric and symmetric) observed in astrophysical environment.

Authors:
;  [1];  [2];  [3];  [4];  [5]
  1. Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan)
  2. Faculty of Exact and Natural Sciences and Andronicashvili Institute of Physics, Javakhishvili Tbilisi University, Tbilisi 0128, Georgia (United States)
  3. GC University, Lahore 54000 (Pakistan)
  4. Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)
  5. (United Kingdom)
Publication Date:
OSTI Identifier:
22598933
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANIONS; ASTROPHYSICS; ASYMMETRY; CHERENKOV RADIATION; COMPRESSION; DENSITY; DISTURBANCES; ELECTRON BEAMS; ELECTRONS; EXCITATION; FOCUSING; INSTABILITY; MASS DIFFERENCE; PERTURBATION THEORY; PLASMA; POSITRONS; SOUND WAVES

Citation Formats

Ehsan, Zahida, Imran, Muhammad, E-mail: imransindhu@hotmail.com, Tsintsadze, N. L., Shah, H. A., Trines, R. M. G. M., and Department of Physics, Lancaster University, Lancaster LA1 4YW. New longitudinal mode and compression of pair ions in plasma. United States: N. p., 2016. Web. doi:10.1063/1.4954651.
Ehsan, Zahida, Imran, Muhammad, E-mail: imransindhu@hotmail.com, Tsintsadze, N. L., Shah, H. A., Trines, R. M. G. M., & Department of Physics, Lancaster University, Lancaster LA1 4YW. New longitudinal mode and compression of pair ions in plasma. United States. doi:10.1063/1.4954651.
Ehsan, Zahida, Imran, Muhammad, E-mail: imransindhu@hotmail.com, Tsintsadze, N. L., Shah, H. A., Trines, R. M. G. M., and Department of Physics, Lancaster University, Lancaster LA1 4YW. 2016. "New longitudinal mode and compression of pair ions in plasma". United States. doi:10.1063/1.4954651.
@article{osti_22598933,
title = {New longitudinal mode and compression of pair ions in plasma},
author = {Ehsan, Zahida and Imran, Muhammad, E-mail: imransindhu@hotmail.com and Tsintsadze, N. L. and Shah, H. A. and Trines, R. M. G. M. and Department of Physics, Lancaster University, Lancaster LA1 4YW},
abstractNote = {Positive and negative ions forming the so-called pair plasma differing in sign of their charge but asymmetric in mass and temperature support a new acoustic-like mode. The condition for the excitation of ion sound wave through electron beam induced Cherenkov instability is also investigated. This beam can generate a perturbation in the pair ion plasmas in the presence of electrons when there is number density, temperature, and mass difference in the two species of ions. Basic emphasis is on the focusing of ion sound waves, and we show how, in the area of localization of wave energy, the density of pair particles increases while electrons are pushed away from that region. Further, this localization of wave is dependent on the shape of the pulse. Considering the example of pancake and bullet shaped pulses, we find that only the former leads to compression of pair ions in the supersonic regime of the focusing region. Here, possible existence of regions where pure pair particles can exist may also be speculated which is not only useful from academic point of view but also to mimic the situation of plasma (electron positron asymmetric and symmetric) observed in astrophysical environment.},
doi = {10.1063/1.4954651},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}
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