Consistency test of the fine-structure constant from the whole ionization history

In cosmology, the fine-structure constant can affect the whole ionization his-tory. However, the previous works confine themselves to the recombination epoch and give various strong constraints on the fine-structure constant. In this paper, we also take the reionization epoch into consideration and do a consistency test of the fine-structure constant from the whole ionization history. From the data combination of Planck 2018, BAO data, SNIa samples, SFR density from UV and IR measurements, and the QHII con-straints, we find the constraint on the fine-structure constant during the recombination epoch is alpha rec/alpha EM = 1.001494+0.002041 -0.002063 and its counterpart during the reionization epoch is alpha rei/alpha EM = 0.854034+0.031678 -0.027209 at 68% C.L.. They are not consistent with each other by 4.64a. A conservative explanation for such a discrepancy is that there are some issues in the data we used. We prefer a calibration of some important parameters involved in reconstruct-ing the reionization history.

Automated summary

In this paper, a consistency test of the fine-structure constant from the whole ionization history is conducted by considering both the recombination epoch and the reionization epoch. The results show a significant inconsistency between the fine-structure constant during these two epochs, suggesting potential issues with the data used.