Analytical Fit to the Luminosity Distance for Flat Cosmologies with a Cosmological Constant
نویسنده
چکیده
Received ; accepted – 2 – ABSTRACT We present a fitting formula for the luminosity and angular diameter distances in cosmological models with pressureless matter, a cosmological constant and zero spatial curvature. The formula has a relative error of less than 0.4% for 0.2 < Ω 0 < 1 for any redshift, and a global relative error of less than 4% for any choice of parameters.
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