Probing Quintessence using BAO imprint on the cross-correlation of weak lensing and post-reionization HI 21 cm signal

Abstract

In this work we investigate the possibility of constraining a thawing Quintessence scalar field model for dark energy. We propose using the imprint of baryon acoustic oscillation (BAO) on the cross-correlation of post-reionization 21-cm signal and galaxy weak lensing convergence field to tomographically measure the angular diameter distance D A (z) and the Hubble parameter H(z). The projected errors in these quantities are then used to constrain the Quintessence model parameters. We find that independent 600hrs radio interferometric observation at four observing frequencies 916MHz, 650 MHz, 520 MHz and 430MHz with a SKA-1-Mid like radio telescope in cross-correlation with a deep weak lensing survey covering half the sky may measure the binned D A and H at a few percent level of sensitivity. The Monte Carlo analysis for a power law thawing Quientessence model gives the 1 − σ marginalized bounds on the initial slope λ i , dark energy density parameter Ω φ0 and the shape of the potential Γ at 8.63%, 10.08% and 9.75% respectively. The constraints improve to 7.66%, 4.39% and 5.86% respectively when a joint analysis with SN and other probes is performed.