2024MNRAS.527.7861G

The Hubble constant (H₀) is a crucial parameter in cosmology. Different cosmic observations have resulted in varying estimates results for H₀, that is the well-known H₀ tension. To address this issue, it is beneficial to use other data set to constrain H₀. In this paper, via the cosmographic approach based on the Friedman-Lemaitre-Robertson-Walker (FLRW) metric to the dispersion measure (DM) of the intergalactic medium DM_IGM(z) of fast radio bursts (FRBs), we obtain the Taylor expansion of 〈DM_IGM(z)〉 in terms of redshift z. Utilizing the uncalibrated type Ia supernaove (SNe Ia) and 18 localized FRBs, we give the cosmological constraints, $H_0=65.5^{+6.4}_{-5.4}$ km s^–1 Mpc^–1 (68 per cent CL), cosmological deceleration parameter q₀ = -0.50 ± 0.20 and the jerk parameter $j_0=-0.1^{+2.0}_{-2.5}$. To demonstrate the impact of parameter degeneracies on our analysis methods, we compare the results using three different forms of f_IGM(z) and two different prior distributions of Ω_b, 0_. After that, we find that the uncertainty in H₀ is not significantly affected by the width of the prior interval of f_IGM(z) and Ω_b, 0_, but the mean value is influenced by the priors for f_IGM(z) and Ω_b, 0_ due to parameter degeneracies with H₀. Employing f_IGM(z) that evolves with redshift, we obtain $H_0=69.0^{+6.7}_{-5.7}$ km s^–1 Mpc^–1. In addition, the mock analyses provide a posterior estimation of H₀ with an accuracy of 4.6 per cent and higher precision for q₀ and j₀ in the near future.