Asking Fast Radio Bursts (FRBs) for More than Reionization History
| Autor: | Shaw, Abinash Kumar, Ghara, Raghunath, Beniamini, Paz, Zaroubi, Saleem, Kumar, Pawan |
|---|---|
| Rok vydání: | 2024 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | We propose different estimators to probe the epoch of reionization (EoR) intergalactic medium (IGM) using the dispersion measure (${\rm DM}$) of the FRBs. We consider three different reionization histories which we can distinguish with a total of $\lesssim 1000$ ${\rm DM}$ measurements during EoR if their redshifts are known. We note that the redshift derivatives of ${\rm DM}$ are also directly sensitive to the reionization history. The major point of this work is exploring the variance in the ${\rm DM}$ measurements and the information encoded in them. We find that the all-sky average $\overline{{\rm DM}}(z)$ gets biased from the LoS fluctuations in the ${\rm DM}$ measurements introduced by the ionization of IGM during EoR. We find that the ratio $\sigma_{\rm DM}/\overline{{\rm DM}}$ depends directly on the ionization bubble sizes as well as the reionization history. On the other hand, we also find that angular variance (coined as $structure$ $function$) of ${\rm DM}$ encodes the information about the duration of reionization and the typical bubble sizes as well. We establish the usefulness of variances in ${\rm DM}$ using toy models of reionization and later verify it with the realistic reionization simulations. Comment: 18 pages, 16 figures, Comments are welcome |
| Databáze: | arXiv |
| Externí odkaz: |
|