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arXiv · 1712.07555

Forecast and analysis of the cosmological redshift drift

Ruth Lazkoz·Iker Leanizbarrutia·Vincenzo Salzano
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Abstract

The cosmological redshift drift could lead to the next step in high-precision cosmic geometric observations, becoming a direct and irrefutable test for cosmic acceleration. In order to test the viability and possible properties of this effect, also called Sandage-Loeb (SL) test, we generate a model independent mock data set so as to compare its constraining power with that of the future mock data sets of Type Ia Supernovae (SNe) and Baryon Acoustic Oscillations (BAO). The performance of those data sets is analyzed by testing several cosmological models with the Markov chain Monte Carlo (MCMC) method, both independently and combining all data sets. Final results show that, in general, SL data sets allow for remarkable constraints on the matter density parameter today $Ω_m$ on every tested model, showing also a great complementarity with SNe and BAO data regarding dark energy (DE) parameters.

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Ruth Lazkoz, Iker Leanizbarrutia, Vincenzo Salzano. 2017-12-20. Forecast and analysis of the cosmological redshift drift. https://doi.org/10.1140/epjc%2Fs10052-017-5479-0

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