简介:A bimodal burst energy distribution of a repeating fast radio burst sourceWe have been carrying out a continuous monitoring campaign of FRB~121102 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST\cite{li18}) since August 2019. Between August 29 and October 29, 2019, we detected 1652 independent burst events (see Supplementary Table 1) in a total of 59.5 hours, covering 1.05 GHz to 1.45 GHz with 98.304 $\mu$s sampling and 0.122 MHz frequency resolution. The total number of previously published bursts from this source was 347 (http://www.frbcat.org). The flux limit of this burst sample is at least three times lower than those of previous observations. The cadence and depth of the observations allow for a statistical study of the repeating bursts, revealing several previously unseen characteristics. The burst rate peaked at 122/hr on September 7th and then 117/hr on October 1st, both measured over the respective one-hour session. In both instances, the burst rate dropped precipitously afterwards. Burst energies vs. epoch are shown in the lower left and the energy histogram on the right, showing bimodality that is itself a function of epoch.Table format:Burst ID | Burst timea(MJD) | DM(pc cm-3) | Width(ms) | Bandwidthb(GHz) | Peak Flux(mJy) | Fluence(Jy ms) | Energy(erg)# Uncertainties in parentheses refer to the last quoted digit.a) Arrival time of burst peak at the solar system barycenter, after correcting to the frequency of 1.5GHz.b) A conservative 30$\%$ fractional error is assumed.--------------------------------------------------------------------------Webpage for demonstrating the Burst Properties & Dataset：The first batch of 535 bursts with the highest signal-to-noise ratio have been uploaded and can be seen at https://fast.cstcloud.cn/datavolume/10.1038.s41586-021-03878-5 .There are two ways to download the FITS format data:1. Batch download for the whole dataset, copy the following commands to the terminal: rsync -av rsync://fast.cstcloud.cn/doi/10.1038/s41586-021-03878-5 .2. Click on "Details" at the right side of the webpage and download the corresponding data file for the burst dynamic spectrum separately.