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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').

17 results found.

  1. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  2. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  3. GRB 231216A: 10.4 m GTC optical upper limit
  4. GRB 231216A: Nanshan/HMT optical upper limit
  5. GRB 231216A: LCOGT Optical Upper Limits
  6. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  7. GRB 231216A: Swift-XRT refined analysis correction
  8. GRB 231216A: Swift-XRT refined Analysis
  9. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  10. GRB 231216A: REM NIR upper limits
  11. GRB 231216A: Swift/UVOT Upper Limits
  12. GRB 231216A: Swift-BAT refined analysis
  13. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  14. GRB 231216A: GIT optical upper limit
  15. GRB 231216A: NOT optical upper limits
  16. GRB 231216A: BOOTES-2/TELMA optical upper limit
  17. GRB 231216A: Swift detection of a burst


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