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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 201021C: TAROT Reunion observatory optical light curve
  2. GRB 201021C: Swift-BAT refined analysis
  3. GRB 201021C: Swift-XRT refined Analysis
  4. GRB 201021C: Fermi GBM detection
  5. GRB 201021C: Swift/UVOT Detection
  6. GRB 201021C: VLT/X-shooter redshift
  7. GRB 201021C: Enhanced Swift-XRT position
  8. GRB 201021C: MASTER optical synchronously observation
  9. GRB 201021C: Swift detection of a burst with an optical counterpart

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