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New Constraints on the Variable Equation of State Parameter from X-Ray Gas Mass Fractions and SNe Ia

J. V. Cunha·L. Marassi·R. C. Santos
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Abstract

Recent measurements are suggesting that we live in a flat Universe and that its present accelerating stage is driven by a dark energy component whose equation of state may evolve in time. Assuming two different parameterizations for the function $ω(z)$, we constrain their free parameters from a joint analysis involving measurements from X-Ray luminosity of galaxy clusters and SNe type Ia data.

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J. V. Cunha, L. Marassi, R. C. Santos. 2006-08-31. New Constraints on the Variable Equation of State Parameter from X-Ray Gas Mass Fractions and SNe Ia. https://doi.org/10.1142/s0218271807010183

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