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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').

11 results found.

  1. GRB 221110A: GRANDMA observations
  2. GRB 221110A: COATLI Second-Epoch Upper Limits
  3. GRB 221110A: GMG upper limit
  4. GRB 221110A: Swift/UVOT Detection and Corrected UVOT Position
  5. GRB 221110A: Swift-BAT refined analysis
  6. GRB 221110A: Swift-XRT refined Analysis
  7. GRB 221110A: Enhanced Swift-XRT position
  8. GRB 221110A: VLT/X-shooter redshift
  9. GRB 221110A: COATLI Afterglow detection
  10. GRB 221110A: LCOGT Optical Afterglow Detection
  11. GRB 221110A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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