{
  "id": "cond-mat/9809356",
  "version": "v1",
  "published": "1998-09-25T17:36:39.000Z",
  "updated": "1998-09-25T17:36:39.000Z",
  "title": "Bose-Einstein condensation of interacting gases",
  "authors": [
    "M. Holzmann",
    "P. Gruter",
    "F. Laloe"
  ],
  "comment": "47 pages, 16 figures, latex file with eps figures",
  "categories": [
    "cond-mat.stat-mech"
  ],
  "abstract": "We study the occurrence of a Bose-Einstein transition in a dilute gas with repulsive interactions, starting from temperatures above the transition temperature. The formalism, based on the use of Ursell operators, allows us to evaluate the one-particle density operator with more flexibility than in mean-field theories, since it does not necessarily coincide with that of an ideal gas with adjustable parameters (chemical potential, etc.). In a first step, a simple approximation is used (Ursell-Dyson approximation), which allow us to recover results which are similar to those of the usual mean-field theories. In a second step, a more precise treatment of the correlations and velocity dependence of the populations in the system is elaborated. This introduces new physical effects, such as a marked change of the velocity profile just above the transition: low velocities are more populated than in an ideal gas. A consequence of this distortion is an increase of the critical temperature (at constant density) of the Bose gas, in agreement with those of recent path integral Monte-Carlo calculations for hard spheres.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1998-09-25T17:36:39.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "bose-einstein condensation",
      "interacting gases",
      "ideal gas",
      "path integral monte-carlo calculations",
      "one-particle density operator"
    ],
    "note": {
      "typesetting": "LaTeX",
      "pages": 47,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "1998cond.mat..9356H"
    }
  }
}