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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').

19 results found.

  1. GRB 230427A: Swift-BAT refined analysis
  2. GRB 230427A: NOT optical upper limit
  3. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  4. GRB 230427A: Swift/UVOT Detection
  5. GRB 230427A: Gaoyazi/GOT optical upper limit
  6. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  7. GRB 230427A: Nanshan/HMT optical upper limit
  8. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  9. GRB 230427A: OSIRIS+/GTC observations
  10. GRB 230427A: Swift-XRT refined Analysis
  11. GRB 230427A: GIT optical upper limit
  12. GRB 230427A: Bassano Bresciano Observatory upper limit
  13. GRB 230427A: GMG upper limit
  14. GRB 230427A : OHP/T193 optical upper limit
  15. GRB 230427A: BOOTES-5/JGT afterglow detection
  16. GRB 230427A: AKO Upper Limit
  17. GRB 230427A: MITSuME Akeno optical upper limits
  18. GRB 230427A: Enhanced Swift-XRT position
  19. GRB 230427A: Swift detection of a burst with an optical counterpart


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