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Title: Lattice melting and rotation in perpetually pulsating equilibria

Abstract

Systems whose potential energies consists of pieces that scale as r{sup -2} together with pieces that scale as r{sup 2}, show no violent relaxation to Virial equilibrium but may pulsate at considerable amplitude forever. Despite this pulsation these systems form lattices when the nonpulsational ''energy'' is low, and these disintegrate as that energy is increased. The ''specific heats'' show the expected halving as the ''solid'' is gradually replaced by the ''fluid'' of independent particles. The forms of the lattices are described here for N{<=}18 and they become hexagonal close packed for large N. In the larger N limit, a shell structure is formed. Their large N behavior is analogous to a {gamma}=5/3 polytropic fluid with a quasigravity such that every element of fluid attracts every other in proportion to their separation. For such a fluid, we study the ''rotating pulsating equilibria'' and their relaxation back to uniform but pulsating rotation. We also compare the rotating pulsating fluid to its discrete counterpart, and study the rate at which the rotating crystal redistributes angular momentum and mixes as a function of extra heat content.

Authors:
 [1];  [1];  [2];  [3];  [4]
  1. Institut d'Astrophysique de Paris UMR 7595, UPMC, 98 bis boulevard d'Arago, 75014 Paris (France)
  2. (United Kingdom)
  3. Lycee Blaise Pascal, 20, rue Alexandre Fleming, 91400 Orsay (France)
  4. University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (United Kingdom)
Publication Date:
OSTI Identifier:
21072271
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevE.75.011125; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMPLITUDES; ANGULAR MOMENTUM; COMPARATIVE EVALUATIONS; CRYSTALS; EQUILIBRIUM; FLUIDS; HCP LATTICES; MELTING; POTENTIAL ENERGY; PULSATIONS; RELAXATION; ROTATION; SPECIFIC HEAT

Citation Formats

Pichon, C., Lynden-Bell, D., Institute of Astronomy and Clare College, Madingley Road, Cambridge CB3 0HA, Pichon, J., and Lynden-Bell, R. Lattice melting and rotation in perpetually pulsating equilibria. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.011125.
Pichon, C., Lynden-Bell, D., Institute of Astronomy and Clare College, Madingley Road, Cambridge CB3 0HA, Pichon, J., & Lynden-Bell, R. Lattice melting and rotation in perpetually pulsating equilibria. United States. doi:10.1103/PHYSREVE.75.011125.
Pichon, C., Lynden-Bell, D., Institute of Astronomy and Clare College, Madingley Road, Cambridge CB3 0HA, Pichon, J., and Lynden-Bell, R. Mon . "Lattice melting and rotation in perpetually pulsating equilibria". United States. doi:10.1103/PHYSREVE.75.011125.
@article{osti_21072271,
title = {Lattice melting and rotation in perpetually pulsating equilibria},
author = {Pichon, C. and Lynden-Bell, D. and Institute of Astronomy and Clare College, Madingley Road, Cambridge CB3 0HA and Pichon, J. and Lynden-Bell, R.},
abstractNote = {Systems whose potential energies consists of pieces that scale as r{sup -2} together with pieces that scale as r{sup 2}, show no violent relaxation to Virial equilibrium but may pulsate at considerable amplitude forever. Despite this pulsation these systems form lattices when the nonpulsational ''energy'' is low, and these disintegrate as that energy is increased. The ''specific heats'' show the expected halving as the ''solid'' is gradually replaced by the ''fluid'' of independent particles. The forms of the lattices are described here for N{<=}18 and they become hexagonal close packed for large N. In the larger N limit, a shell structure is formed. Their large N behavior is analogous to a {gamma}=5/3 polytropic fluid with a quasigravity such that every element of fluid attracts every other in proportion to their separation. For such a fluid, we study the ''rotating pulsating equilibria'' and their relaxation back to uniform but pulsating rotation. We also compare the rotating pulsating fluid to its discrete counterpart, and study the rate at which the rotating crystal redistributes angular momentum and mixes as a function of extra heat content.},
doi = {10.1103/PHYSREVE.75.011125},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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