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Minimal Angular Size of Distant Sources in Open, $Λ$CDM, and Scalar Field Cosmologies

J. A. S. Lima·J. S. Alcaniz
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Abstract

We propose a simple method for determining the redshift $z_{m}$ at which the angular size of an extragalactic source with fixed proper diameter takes its minimal value. A closed analytical expression, which is quite convenient for numerical evaluation is derived. The method is exemplified with the following FRW type expanding universes: the open matter dominated models ($Ω_Λ= 0$), a critical density model with cosmological constant ($Ω_Λ \neq 0$), and the class of scalar field cosmologies proposed by Ratra and Peebles. The influence of systematic evolutionary effects is briefly discussed.

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J. A. S. Lima, J. S. Alcaniz. 1999-07-08. Minimal Angular Size of Distant Sources in Open, $Λ$CDM, and Scalar Field Cosmologies. https://doi.org/10.1023/a%3A1001988831930

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