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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 Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

7 results found.

  1. Fermi-LAT gamma-ray observations of IceCube-230727A
  2. IceCube-230727A: No candidates from the Zwicky Transient Facility
  3. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 230727A: AstroSat CZTI detection
  5. GRB 230727A: Swift/BAT-GUANO detection of a burst
  6. IceCube-230727A - IceCube observation of a high-energy neutrino candidate track-like event
  7. GRB 230727A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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