Revealing the Temporally Stable Bimodal Energy Distribution of FRB 20121102A with a Tripled Burst Set from AI Detections

We performed a deep search on the archival FAST L-band observations during the extreme active phase (from Aug. 2019 to Oct. 2019) of the repeating source FRB 20121102A and obtained a burst sample of 5496 bursts. The burst rate peaked at 456 hr$^{-1}$ during a one-hour observation on September 7th, nearly four times the rate of the previous burst set. The much enhanced completeness enables a refined analysis of the temporal behavior of energy distribution, revealing that the bimodal energy distribution remains stable over time. It is rather an intrinsic feature of the emission mechanisms than a consequence of co-evolving with the burst rate. The manuscript is under review at Nature Communications and is available on arXiv:2510.07002. Please note that while the dataset linked in this manuscript is now finalized, an updated version of the manuscript PDF is forthcoming. We encourage you to check arXiv and wait for the latest manuscript.