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arXiv · 2108.11363

The Effective Field Theory of Large-Scale Structure and Multi-tracer

Thiago Mergulhão·Henrique Rubira·Rodrigo Voivodic·L. Raul Abramo
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Abstract

We study the performance of the perturbative bias expansion when combined with the multi-tracer technique, and their impact on the extraction of cosmological parameters. We consider two populations of tracers of large-scale structure and perform a series of Markov chain Monte Carlo analysis for those two tracers separately. The constraints in $\omega_{\rm cdm}$ and $h$ using multi-tracer are less biased and approximately $60\%$ better than those obtained for a single tracer. The multi-tracer approach also provides stronger constraints on the bias expansion parameters, breaking degeneracies between them and with their error being typically half of the single-tracer case. Finally, we studied the impacts caused in parameter extraction when including a correlation between the stochastic field of distinct tracers. We also include a study with galaxies showing that multi-tracer still lead to substantial gains in the cosmological parameters.

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Thiago Mergulhão, Henrique Rubira, Rodrigo Voivodic, L. Raul Abramo. 2021-08-25. The Effective Field Theory of Large-Scale Structure and Multi-tracer. https://doi.org/10.1088/1475-7516%2F2022%2F04%2F021

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