SIMBAD references

Fast radio bursts (FRBs) are enigmatic radio pulses whose origins are poorly understood. The dispersion measure of host galaxy (${\rm DM_{host}}$) provides critical insights into the local environment of FRB sources. In this study, we analyse a sample of 117 well-localized FRBs to investigate the statistical properties of ${\rm DM_{host}}$ and its potential correlations with host galaxy parameters, including redshift, stellar mass, star formation rate (SFR), and galaxy age. Our results reveal that ${\rm DM_{host}}$ is consistent with a lognormal distribution, with the mean $\mu _{\rm host}=5.03\pm 0.02$ and standard deviation $\sigma _{\rm host} = 0.96\pm 0.03$, which corresponds to a median value ${\rm Med}({\rm DM_{host}})=\exp (\mu _{\rm host})=153\pm 3~{\rm pc~cm^{-3}}$. We find a moderate positive correlation between ${\rm DM_{host}}$ and redshift, but no statistically significant correlations are found between ${\rm DM_{host}}$ and stellar mass, SFR, or galaxy age. Our findings highlight the importance of ${\rm DM_{host}}$ as a diagnostic tool for unravelling FRB origins, and underscore the need for future FRB surveys with deep multiwavelength host galaxy follow-up.