skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Caustic ring singularity

Abstract

I investigate the caustics produced by the fall of collisionless dark matter in and out of a galaxy in the limit of negligible velocity dispersion. The outer caustics are spherical shells enveloping the galaxy. The inner caustics are rings. These are located near where the particles with the most angular momentum are at their distance of closest approach to the galactic center. The surface of a caustic ring is a closed tube whose cross section is a D[sub [minus]4] catastrophe. It has three cusps amongst which exists a discrete Z[sub 3] symmetry. A detailed analysis is given in the limit where the flow of particles is axially and reflection symmetric and where the transverse dimensions of the ring are small compared to the ring radius. Five parameters describe the caustic in that limit. The relations between these parameters and the initial velocity distribution of the particles are derived. The structure of the caustic ring is used to predict the shape of the bump produced in a galactic rotation curve by a caustic ring lying in the galactic plane. [copyright] [ital 1999] [ital The American Physical Society]

Authors:
 [1]
  1. (Department of Physics, University of Florida, Gainesville, Florida 32611 (United States))
Publication Date:
OSTI Identifier:
6470936
Alternate Identifier(s):
OSTI ID: 6470936
Resource Type:
Journal Article
Journal Name:
Physical Review, D
Additional Journal Information:
Journal Volume: 60:6; Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GALAXIES; NONLUMINOUS MATTER; SYMMETRY; MATTER 661300* -- Other Aspects of Physical Science-- (1992-)

Citation Formats

Sikivie, P. Caustic ring singularity. United States: N. p., 1999. Web. doi:10.1103/PhysRevD.60.063501.
Sikivie, P. Caustic ring singularity. United States. doi:10.1103/PhysRevD.60.063501.
Sikivie, P. Wed . "Caustic ring singularity". United States. doi:10.1103/PhysRevD.60.063501.
@article{osti_6470936,
title = {Caustic ring singularity},
author = {Sikivie, P.},
abstractNote = {I investigate the caustics produced by the fall of collisionless dark matter in and out of a galaxy in the limit of negligible velocity dispersion. The outer caustics are spherical shells enveloping the galaxy. The inner caustics are rings. These are located near where the particles with the most angular momentum are at their distance of closest approach to the galactic center. The surface of a caustic ring is a closed tube whose cross section is a D[sub [minus]4] catastrophe. It has three cusps amongst which exists a discrete Z[sub 3] symmetry. A detailed analysis is given in the limit where the flow of particles is axially and reflection symmetric and where the transverse dimensions of the ring are small compared to the ring radius. Five parameters describe the caustic in that limit. The relations between these parameters and the initial velocity distribution of the particles are derived. The structure of the caustic ring is used to predict the shape of the bump produced in a galactic rotation curve by a caustic ring lying in the galactic plane. [copyright] [ital 1999] [ital The American Physical Society]},
doi = {10.1103/PhysRevD.60.063501},
journal = {Physical Review, D},
issn = {0556-2821},
number = ,
volume = 60:6,
place = {United States},
year = {1999},
month = {9}
}