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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').

18 results found.

  1. GRB 191019A: Zadko Telescope optical observations
  2. GRB 191019A: NOT optical afterglow and host association confirmation
  3. GRB 191019A: Nanshan-0.6m optical observations
  4. GRB 191019A: Swift/UVOT Detection
  5. HAWC-191019A: Retraction of burst alert
  6. HAWC-191019A: No Neutrino Counterpart detected with ANTARES
  7. GRB 191019A: Swift-XRT updated analysis
  8. GRB 191019A: Swift-BAT refined analysis
  9. GRB 191019A: Swift-XRT refined Analysis
  10. GRB 191019A: Enhanced Swift-XRT position
  11. GRB 191019A: GROND observations
  12. GRB 191019A: NOT optical spectroscopy of candidate counterpart
  13. GRB 191019A: NOT optical observations
  14. Alert from the HAWC Burst Monitor HAWC-191019A
  15. GRB 191019A: TSHAO optical observations, probable afterglow and host galaxy
  16. GRB 191019A: Swift-XRT observations
  17. GRB 191019A: MASTER optical observation
  18. GRB 191019A: Swift detection of a burst


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