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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').

9 results found.

  1. GRB 200803A: Chilescope optical upper limit
  2. GRB 200803A: AstroSat CZTI detection
  3. GRB 200803A: Fermi GBM detection
  4. GRB 200803A: Swift-XRT afterglow detection
  5. GRB 200803A: Fermi-LAT detection
  6. GRB 200803A: MASTER optical counterpart discovery
  7. GRB 200803A: Tiled Swift observations
  8. Fermi GRB 200803A: Global MASTER-Net observations report
  9. GRB 200803A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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