An Analytical Approximation of the Luminosity Distance in Flat Cosmologies with a Cosmological Constant(Astrophysics and Cosmology)

スポンサーリンク

概要

• 論文の詳細を見る

• We present an analytical approximation formula for the luminosity distance in spatially flat cosmologies with dust and a cosmological constant. Apart from the overall factor, the effect of non-zero cosmological constant in our formula is written simply in terms of a rational function. We also show the approximate formulae for the Dyer-Roeder distance (the empty beam case) and the generalized angular diameter distance from redshift z_1 to z_2, which are particularly useful in analyzing the gravitational lens effects. Our formulae are widely applicable over the range of the density parameter and the redshift with sufficiently small uncertainties. In particular, in the range of density parameter 0.3 &le Ω_m &le 1 and redshift 0.03 &le z &le 1000, the relative error for the luminosity distance by our formula is always smaller than that of the recent work by Wickramasinghe and Ukwatta (2010). Hence, we hope that our formulae will be an efficient and useful tool for exploring various problems in observational cosmology.

• 2012-01-25

著者

• Kasai Masumi

  Graduate School Of Science And Technology Hirosaki University

• Adachi Masaru

  Graduate School Of Science And Technology Hirosaki University

関連論文

• Secular Increase of the Astronomical Unit : a Possible Explanation in Terms of the Total Angular-Momentum Conservation Law
• Apparent Acceleration through Large-Scale Inhomogeneities : Post-Friedmannian Effects of Inhomogeneities on the Luminosity Distance(Astrophysics and Relativity)
• Perturbative Approach to the Gravitational Lensing by a Non-Spherically Distorted Compact Object(Astrophysics and Cosmology)
• An Analytical Approximation of the Luminosity Distance in Flat Cosmologies with a Cosmological Constant(Astrophysics and Cosmology)
• An Analytical Approximation of the Luminosity Distance in Flat Cosmologies with a Cosmological Constant

スポンサーリンク