The origin of fast radio bursts and key sciences to be addressed

Tetsuya Hashimoto^1*, Tomotsugu Goto², Bo Han Chen², Simon C.-C. Ho², Tiger Y.-Y. Hsiao², Yi Hang Valerie Wong², Alvina Y. L. On^2,3, Seong Jin Kim², Ece Kilerci-Eser⁴, Kai-Chun Huang¹, Daryl Joe D. Santos⁵, Ting-Yi Lu⁶, Leo Y.-W. Lin², Cossas, K.-W. Wu², Kaustubha Sen², Chih-Teng Ling²

¹Department of Physics, National Chung Hsing University, Taichung, Taiwan
²Institute of Astronomy, National Tsing Hua University, Hsinchu, Taiwan
³Mullard Space Science Laboratory, University College London, Surrey, UK
⁴Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul, Turkey
⁵International Max-Planck Research School, Max Planck Institutes, Bonn, Germany
⁶Dark Cosmology Centre, University of Copenhagen, Copenhagen, Denmark

* Presenter:Tetsuya Hashimoto, email:tetsuya@phys.nchu.edu.tw

Fast radio bursts (FRBs) are mysterious millisecond pulses in radio, most of which happen in distant galaxies. Revealing the origin of FRBs is becoming central in astronomy. Previous works suffer from the observational difficulty of the FRB localization and small sample sizes, which hamper a conclusion. To overcome this problem, we use a unique statistical approach to strongly constrain the origin of FRBs, being free from the localization problem. Here we show the energy functions of FRBs selected from the recently released CHIME catalogue. We use a homogeneous sample of 164 non-repeating FRB sources, which are about one order of magnitude larger than previously investigated samples. The energy functions and volumetric rates of non-repeating FRBs decrease towards higher redshifts similar to the cosmic stellar-mass density evolution. Our results indicate that the event rate of non-repeating FRBs is likely controlled by old populations rather than young populations which are traced by the cosmic star-formation rate density. This suggests old populations such as old neutron stars and black holes as more likely progenitors of non-repeating FRBs. Furthermore, FRBs allow us to address key questions in astronomy and physics including dark energy, cosmic reionization, testing general relativity. In my talk, I will also summarize our recent papers to address these key sciences using FRBs.

Keywords: Fast radio bursts, Galaxies, Dark energy, Cosmic reionization, General relativity