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Probabilities for gravitational lensing by point masses in a locally inhomogeneous universeProbability functions for gravitational lensing by point masses that incorporate Poisson statistics and flux conservation are formulated in the Dyer-Roeder construction. Optical depths to lensing for distant sources are calculated using both the method of Press and Gunn (1973) which counts lenses in an otherwise empty cone, and the method of Ehlers and Schneider (1986) which projects lensing cross sections onto the source sphere. These are then used as parameters of the probability density for lensing in the case of a critical (q0 = 1/2) Friedmann universe. A comparison of the probability functions indicates that the effects of angle-averaging can be well approximated by adjusting the average magnification along a random line of sight so as to conserve flux.
Document ID
19890037381
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Isaacson, Jeffrey A.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Canizares, Claude R.
(MIT Cambridge, MA, United States)
Date Acquired
August 14, 2013
Publication Date
January 15, 1989
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 336
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
89A24752
Funding Number(s)
CONTRACT_GRANT: NAG8-494
Distribution Limits
Public
Copyright
Other

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