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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').

10 results found.

  1. GRB 180821A: VLT observations
  2. GRB 180821A: Swift/UVOT Upper Limits
  3. GRB 180821A: Swift-BAT refined analysis
  4. GRB 180821A: iTelescope counterpart is not the afterglow
  5. GRB 180821A: Swift-XRT refined Analysis
  6. GRB 180821A: LCO Siding Springs observations
  7. GRB 180821A: Enhanced Swift-XRT position
  8. GRB 180821A: iTelescope optical afterglow detection
  9. GRB 180821A: BOOTES-3/YA optical observations
  10. GRB 180821A: Swift detection of a burst

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