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arXiv · 2205.03867

Improvement of cosmological constraints with the cross correlation between line-of-sight optical galaxy and FRB dispersion measure

Chenghao Zhu·Jiajun Zhang
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Abstract

Fast Radio Bursts (hereafter FRBs) can be used in cosmology by studying the Dispersion Measure (hereafter DM) as a function of redshift. The large scale structure of matter distribution is regarded as a major error budget for such application. Using optical galaxy and dispersion measure mocks built from N-body simulations, we have shown that the galaxy number density can be used as a tracer for large scale electron density and help improve the measurement of DM as a function of redshift. We have shown that, using the line-of-sight galaxy number counts within 1' around the given localized FRB source can help improve the cosmological parameter constraints by more than 20%.

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Chenghao Zhu, Jiajun Zhang. 2022-05-08. Improvement of cosmological constraints with the cross correlation between line-of-sight optical galaxy and FRB dispersion measure. https://doi.org/10.1103/physrevd.106.023513

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