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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Event Groups by event name (e.g. 'GRB 123456A', 'GRB123456A', '123456A').
GRB 200114A
    GRB 200112A
      GRB 200111A
        ANTARES 200108A
          IceCube-200109A
            GRB 200109A
              GRB 200109.07
                IceCube-200107A
                  LIGO/Virgo S200108v
                    GRB 200107B
                      GRB 200107.81
                        LIGO/Virgo S200105ae
                          GRB 200105A
                            GRB 200103A
                              IceCube-191231A
                                GRB 200101A
                                  GRB 191227B
                                    GRB 191228A
                                      LIGO/Virgo S191222n
                                        GRB 191228.00
                                          GRB 191227A
                                            GRB 191227.07
                                              GRB 191226.25
                                                GRB 191226.02
                                                  LIGO/Virgo S191225aq
                                                    GRB 191225B
                                                      GRB 191225A
                                                        GRB 191220.59
                                                          GRB 191221B
                                                            Baksan Neutrino Observatory Alert 191222.09
                                                              GRB 191221A
                                                                GRB 191220A
                                                                  GRB 191220.56
                                                                    LIGO/Virgo S191220af
                                                                      LIGO/Virgo S191216ap
                                                                        GRB 191218A
                                                                          LIGO/Virgo G191216ap
                                                                            LIGO/Virgo S191215w
                                                                              ZTF19acyldun
                                                                                IceCube-191215A
                                                                                  GRB 191213A
                                                                                    GRB 191213B
                                                                                      LIGO/Virgo S191213ai
                                                                                        LIGO/Virgo S191213g
                                                                                          LIGO/Virgo S191205ah
                                                                                            LIGO/Virgo S191212q
                                                                                              GRB 191210A
                                                                                                GRB 191207A
                                                                                                  GRB 191102A
                                                                                                    GRB 191105B
                                                                                                      LIGO/Virgo S191204r
                                                                                                        GRB 191205A
                                                                                                          IceCube-191204A
                                                                                                            GRB 191130A
                                                                                                              GRB 191202A
                                                                                                                GRB 191203A
                                                                                                                  GRB 191004A
                                                                                                                    GRB 191201A
                                                                                                                      LIGO/Virgo S191129u
                                                                                                                        GRB 191129A
                                                                                                                          Baksan Neutrino Observatory Alert 191128.17
                                                                                                                            IceCube-191122A
                                                                                                                              Baksan Neutrino Observatory Alert 191127.25
                                                                                                                                GRB 191125B
                                                                                                                                  GRB 191125A
                                                                                                                                    Baksan Neutrino Observatory Alert 191124.13
                                                                                                                                      LIGO/Virgo S191124be
                                                                                                                                        GRB 191123A
                                                                                                                                          GRB 191122A
                                                                                                                                            GRB 191116A
                                                                                                                                              LIGO/Virgo S191120at
                                                                                                                                                LIGO/Virgo S191120aj
                                                                                                                                                  IceCube-191119A
                                                                                                                                                    GRB 191118A
                                                                                                                                                      GRB 191117B
                                                                                                                                                        LIGO/Virgo S191117j
                                                                                                                                                          GRB 191117A
                                                                                                                                                            GRB 191115A
                                                                                                                                                              GRB 191113A
                                                                                                                                                                GRB 191112A
                                                                                                                                                                  GRB 191111B
                                                                                                                                                                    LIGO/Virgo S191110af
                                                                                                                                                                      GRB 191111A
                                                                                                                                                                        LIGO/Virgo S191110x
                                                                                                                                                                          GRB 191110A
                                                                                                                                                                            LIGO/Virgo S191109d
                                                                                                                                                                              GRB 191108A
                                                                                                                                                                                LIGO/Virgo S191105e
                                                                                                                                                                                  GRB 191106A
                                                                                                                                                                                    SGR 1935+2154
                                                                                                                                                                                      GRB 191105.01
                                                                                                                                                                                        GRB 191104C
                                                                                                                                                                                          GRB 191104B
                                                                                                                                                                                            GRB 191104A
                                                                                                                                                                                              GRB 191031E
                                                                                                                                                                                                GRB 191101A
                                                                                                                                                                                                  Baksan Neutrino Observatory Alert 191102.06
                                                                                                                                                                                                    GRB 191101.88
                                                                                                                                                                                                      GRB 191101B
                                                                                                                                                                                                        GRB 191031D

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                                                                                                                                                                                                          Download all Circulars as a .tar.gz archive:
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