Portal de Periódicos da CAPES

CHIME/FRB Discovery of Eight New Repeating Fast Radio Burst Sources

2019; IOP Publishing; Volume: 885; Issue: 1 Linguagem: Inglês

10.3847/2041-8213/ab4a80

2041-8213

Bridget C. Andersen, Kevin Bandura, Mohit Bhardwaj, Paula Boubel, M. M. Boyce, P. J. Boyle, Charanjot Brar, Tomas Cassanelli, Pragya Chawla, Davor Čubranić, Meiling Deng, M. Dobbs, Mateus Fandino, Emmanuel Fonseca, B. M. Gaensler, A. J. Gilbert, Utkarsh Giri, Deborah C. Good, M. Halpern, Alex S. Hill, G. Hinshaw, C. Höfer, Alexander Josephy, V. M. Kaspi, R. Kothes, T. L. Landecker, Dustin Lang, Dongzi Li, Hsiu-Hsien Lin, Kiyoshi W. Masui, Juan Mena-Parra, Marcus Merryfield, Ryan Mckinven, Daniele Michilli, Nikola Milutinović, Arun Naidu, Laura Newburgh, Cherry Ng, C. Patel, Ue‐Li Pen, Tristan Pinsonneault-Marotte, Ziggy Pleunis, Masoud Rafiei-Ravandi, Mubdi Rahman, S. M. Ransom, Andre Renard, Paul Scholz, Seth R. Siegel, Saurabh Singh, Kendrick M. Smith, I. H. Stairs, Shriharsh P. Tendulkar, Ian Tretyakov, K. Vanderlinde, Prakarsh Yadav, A. V. Zwaniga,

Astrophysical Phenomena and Observations

We report on the discovery of eight repeating fast radio burst (FRB) sources found using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. These sources span a dispersion measure (DM) range of 103.5 to 1281 pc cm$^{-3}$. They display varying degrees of activity: six sources were detected twice, another three times, and one ten times. These eight repeating FRBs likely represent the bright and/or high-rate end of a distribution of infrequently repeating sources. For all sources, we determine sky coordinates with uncertainties of $\sim$10$^\prime$. FRB 180916.J0158+65 has a burst-averaged DM = $349.2 \pm 0.3$ pc cm$^{-3}$ and a low DM excess over the modelled Galactic maximum (as low as $\sim$20 pc cm$^{-3}$); this source also has a Faraday rotation measure (RM) of $-114.6 \pm 0.6$ rad m$^{-2}$, much lower than the RM measured for FRB 121102. FRB 181030.J1054+73 has the lowest DM for a repeater, $103.5 \pm 0.3$ pc cm$^{-3}$, with a DM excess of $\sim$ 70 pc cm$^{-3}$. Both sources are interesting targets for multi-wavelength follow-up due to their apparent proximity. The DM distribution of our repeater sample is statistically indistinguishable from that of the first 12 CHIME/FRB sources that have not repeated. We find, with 4$\sigma$ significance, that repeater bursts are generally wider than those of CHIME/FRB bursts that have not repeated, suggesting different emission mechanisms. Our repeater events show complex morphologies that are reminiscent of the first two discovered repeating FRBs. The repetitive behavior of these sources will enable interferometric localizations and subsequent host galaxy identifications.