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A repeating fast radio burst


Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances1,2,3,4,5,6,7,8. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections9. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events10. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst4. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star11,12.

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Figure 1: Discovery and follow-up detections of FRB 121102.
Figure 2: FRB 121102 burst morphologies and spectra.


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We thank the staff of the Arecibo Observatory, and in particular A. Venkataraman, H. Hernandez, P. Perillat and J. Schmelz, for their continued support and dedication to enabling observations like those presented here. We also thank our commensal observing partners from the Arecibo ‘Zone of Avoidance’ team, in particular T. McIntyre and T. Henning. We thank M. Kramer for suggestions. The Arecibo Observatory is operated by SRI International under a cooperative agreement with the National Science Foundation (AST-1100968), and in alliance with Ana G. Méndez-Universidad Metropolitana, and the Universities Space Research Association. These data were processed using the McGill University High Performance Computing Centre operated by Compute Canada and Calcul Québec. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The research leading to these results has received funding from the European Research Council (ERC) under the European Union’s Seventh Framework Programme (FP7/2007-2013). L.G.S., P.C.C.F. and P.L. gratefully acknowledge financial support from the ERC Starting Grant BEACON under contract number 279702. J.W.T.H. is an NWO Vidi Fellow and gratefully acknowledges funding for this work from ERC Starting Grant DRAGNET under contract number 337062. Work at Cornell (J.M.C., S.C., A.B.) was supported by NSF grants AST-1104617 and AST-1008213. V.M.K. holds the Lorne Trottier Chair in Astrophysics and Cosmology and a Canadian Research Chair in Observational Astrophysics and received additional support from NSERC via a Discovery Grant and Accelerator Supplement, by FQRNT via the Centre de Recherche Astrophysique de Québec, and by the Canadian Institute for Advanced Research. J.v.L. acknowledges funding for this research from an ERC Consolidator Grant under contract number 617199. Pulsar research at UBC is supported by an NSERC Discovery Grant and by the Canadian Institute for Advanced Research.

Author information




L.G.S. and J.W.T.H. led the design and execution of the observing campaign described here. P.S. performed the analysis that discovered the radio bursts. More detailed analysis of the signal properties was done by L.G.S., P.S., S.M.R., M.A.M., J.W.T.H., S.C. and J.M.C. L.G.S., J.W.T.H., P.S. and V.M.K. led the writing of the manuscript. All authors contributed substantially to the interpretation of the analysis results and to the final version of the manuscript.

Corresponding author

Correspondence to J. W. T. Hessels.

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The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Table 1 Arecibo FRB 121102 discovery and follow-up observations
Extended Data Table 2 FRB 121102 gridding positions

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Spitler, L., Scholz, P., Hessels, J. et al. A repeating fast radio burst. Nature 531, 202–205 (2016).

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