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Title: Drift and separation in collisionality gradients

Abstract

Here we identify a single-particle drift resulting from collisional interactions with a background species, in the presence of a collisionality gradient and background net flow. We also analyze this drift in different limits, showing how it reduces to the well known impurity pinch for high-Zi impurities. We find that in the low-temperature, singly ionized limit, the magnitude of the drift becomes mass-dependent and energy-dependent. Furthermore, by solving for the resulting diffusion-advection motion, we propose a mass-separation scheme that takes advantage of this drift, and analyze the separative capability as a function of collisionally dissipated energy.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [1]
  1. Princeton Univ., NJ (United States). Dept. of Astronomical Sciences; Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. Univ. of Paris XI, Palaiseau (France). Dept. of Physics
  3. Centre National de la Recherche Scientifique (CNRS), Toulous (France). Plasma Lab. and Energy Conversion
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1395004
Grant/Contract Number:
AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 8; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS

Citation Formats

Ochs, I. E., Rax, J. M., Gueroult, R., and Fisch, N. J. Drift and separation in collisionality gradients. United States: N. p., 2017. Web. doi:10.1063/1.4994327.
Ochs, I. E., Rax, J. M., Gueroult, R., & Fisch, N. J. Drift and separation in collisionality gradients. United States. doi:10.1063/1.4994327.
Ochs, I. E., Rax, J. M., Gueroult, R., and Fisch, N. J. 2017. "Drift and separation in collisionality gradients". United States. doi:10.1063/1.4994327.
@article{osti_1395004,
title = {Drift and separation in collisionality gradients},
author = {Ochs, I. E. and Rax, J. M. and Gueroult, R. and Fisch, N. J.},
abstractNote = {Here we identify a single-particle drift resulting from collisional interactions with a background species, in the presence of a collisionality gradient and background net flow. We also analyze this drift in different limits, showing how it reduces to the well known impurity pinch for high-Zi impurities. We find that in the low-temperature, singly ionized limit, the magnitude of the drift becomes mass-dependent and energy-dependent. Furthermore, by solving for the resulting diffusion-advection motion, we propose a mass-separation scheme that takes advantage of this drift, and analyze the separative capability as a function of collisionally dissipated energy.},
doi = {10.1063/1.4994327},
journal = {Physics of Plasmas},
number = 8,
volume = 24,
place = {United States},
year = 2017,
month = 7
}

Journal Article:
Free Publicly Available Full Text
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