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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').

12 results found.

  1. GRB 210504A: LCO Optical Afterglow Detection
  2. GRB 210504A: Lowell Discovery Telescope optical observations
  3. GRB 210504A: VLT X-shooter redshift
  4. GRB 210504A: Swift-XRT refined Analysis
  5. GRB 210504A: Swift-BAT refined analysis
  6. GRB 210504A: NOT optical afterglow detection
  7. GRB 210504A: MITSuME Akeno optical upper limits
  8. GRB 210504A: AST3-3 YaoAn Optical Upper Limit
  9. GRB 210504A: Swift/UVOT Detection
  10. GRB 210504A: BOOTES-4/MET optical upper limit
  11. GRB 210504A: update on the BAT trigger time and burst duration
  12. GRB 210504A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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