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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').
LIGO/Virgo/KAGRA S230706ah
    LIGO/Virgo/KAGRA S230704f
      GRB 230701B
        LIGO/Virgo/KAGRA S230702an
          GRB 230702A
            GRB 230701A
              LIGO/Virgo/KAGRA S230630bq
                LIGO/Virgo/KAGRA S230630am
                  LIGO/Virgo/KAGRA S230628ax
                    GRB 230628.93
                      GRB 230628E
                        GRB 230628D
                          GRB 230628C
                            GRB 230628B
                              LIGO/Virgo/KAGRA S230516az
                                GRB 230628A
                                  LIGO/Virgo/KAGRA S230527c
                                    GRB 230626A
                                      LIGO/Virgo/Kagra S230627c
                                        LIGO/Virgo/KAGRA S230627c
                                          GRB 230625B
                                            GRB 230625A
                                              GRB 230623B
                                                LIGO/Virgo/KAGRA S230624av
                                                  GRB 230623A
                                                    LIGO/Virgo/KAGRA S230622ba
                                                      LIGO/Virgo S230622e
                                                        LIGO/Virgo S230621bq
                                                          LIGO/Virgo S230621ad
                                                            GRB 230622A
                                                              GRB 230621A
                                                                LIGO/Virgo S230620ad
                                                                  LIGO/Virgo S230620au
                                                                    LIGO/Virgo S230620al
                                                                      LIGO/Virgo S230620af
                                                                        LIGO/Virgo S230620z
                                                                          LIGO/Virgo S230620w
                                                                            LIGO/Virgo S230619bg
                                                                              LIGO/Virgo S230620g
                                                                                LIGO/Virgo S230619ay
                                                                                  LIGO/Virgo S230619bd
                                                                                    LIGO/Virgo S230619bb
                                                                                      LIGO/Virgo S230619as
                                                                                        LIGO/Virgo S230619ap
                                                                                          ZTF23aaoohpy
                                                                                            LIGO/Virgo S230619i
                                                                                              LIGO/Virgo S230619aa
                                                                                                LIGO/Virgo S230619x
                                                                                                  LIGO/Virgo S230619e
                                                                                                    LIGO/Virgo S230618at
                                                                                                      LIGO/Virgo S230618ba
                                                                                                        LIGO/Virgo S230618az
                                                                                                          LIGO/Virgo S230618ae
                                                                                                            LIGO/Virgo S230618aq
                                                                                                              LIGO/Virgo S230618y
                                                                                                                LIGO/Virgo S230618s
                                                                                                                  LIGO/Virgo S230618r
                                                                                                                    LIGO/Virgo S230616aa
                                                                                                                      LIGO/Virgo S230615an
                                                                                                                        LIGO/Virgo S230615ak
                                                                                                                          LIGO/Virgo S230617ba
                                                                                                                            LIGO/Virgo S230618k
                                                                                                                              LIGO/Virgo S230618d
                                                                                                                                LIGO/Virgo S230617bc
                                                                                                                                  LIGO/Virgo S230617aq
                                                                                                                                    LIGO/Virgo S230617ab
                                                                                                                                      LIGO/Virgo S230617aj
                                                                                                                                        GRB 230618B
                                                                                                                                          GRB 230618A
                                                                                                                                            GRB 230617A
                                                                                                                                              GRB 230616A
                                                                                                                                                LIGO/Virgo S230616s
                                                                                                                                                  LIGO/Virgo S230615be
                                                                                                                                                    LIGO/Virgo S230615af
                                                                                                                                                      LIGO/Virgo S230616j
                                                                                                                                                        LIGO/Virgo/KAGRA S230615az
                                                                                                                                                          LIGO/Virgo S230615av
                                                                                                                                                            LIGO/Virgo S230615az
                                                                                                                                                              LIGO/Virgo S230615ax
                                                                                                                                                                LIGO/Virgo S230615k
                                                                                                                                                                  LIGO/Virgo S230615t
                                                                                                                                                                    GRB 230614C
                                                                                                                                                                      LIGO/Virgo S230615i
                                                                                                                                                                        LIGO/Virgo S230613at
                                                                                                                                                                          LIGO/Virgo S230614ac
                                                                                                                                                                            LIGO/Virgo S230614t
                                                                                                                                                                              LIGO/Virgo S230614o
                                                                                                                                                                                GRB 230614B
                                                                                                                                                                                  GRB 230614A
                                                                                                                                                                                    LIGO/Virgo S230611be
                                                                                                                                                                                      LIGO/Virgo S230611l
                                                                                                                                                                                        LIGO/Virgo S230609u
                                                                                                                                                                                          GRB 230608A
                                                                                                                                                                                            LIGO/Virgo S230608aw
                                                                                                                                                                                              LIGO/Virgo/KAGRA S230609u
                                                                                                                                                                                                LIGO/Virgo S230608as
                                                                                                                                                                                                  LIGO/Virgo S230609a
                                                                                                                                                                                                    LIGO/Virgo S230608ah
                                                                                                                                                                                                      LIGO/Virgo S230608q
                                                                                                                                                                                                        ZTF23aamxeqf

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                                                                                                                                                                                                          Download all Circulars as a .tar.gz archive:
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