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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 200809B: Fermi GBM detection
  2. Fermi GRB 200809B: Global MASTER-Net observations report
  3. GRB 200809B: BOOTES-3/YA optical upper limit
  4. GRB 200809B: Swift-XRT afterglow detection
  5. GRB 200809B: MAXI/GSC detection
  6. GRB 200809B: Swift ToO observations
  7. GRB 200809B: AstroSat CZTI detection
  8. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  9. GRB 200809B: Fermi GBM Final Real-time Localization

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Download all Circulars as a .tar.gz archive:
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