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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').

6 results found.

  1. Konus-Wind detection of GRB 230418A
  2. IPN triangulation of GRB 230418A (short)
  3. GRB 230418A: AstroSat CZTI detection
  4. GRB 230418A: AGILE detection
  5. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  6. GRB 230418A: Fermi GBM Observation


Download all Circulars as a .tar.gz archive:
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