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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').

15 results found.

  1. GRB 160227A: MAXI/GSC detection
  2. GRB 160227A: LOAO 1.0m optical detection
  3. GRB 160227A: McDonald 0.8m Detection
  4. GRB 160227A: Swift/UVOT Detection
  5. GRB 160227A: MASTER prompt OT Detection and LC
  6. GRB 160227A: AROMA-N Optical Observation
  7. GRB 160227A: NOT redshift
  8. GRB 160227A, Swift-BAT refined analysis
  9. GRB 160227A: Swift-XRT refined Analysis
  10. GRB 160227A: Enhanced Swift-XRT position
  11. GRB 160227A: MAXI/GSC detection
  12. GRB 160227A: ISON-Kislovodsk optical observation
  13. GRB 160227A: Mt. Terskol observatory optical observation
  14. GRB 160227A: MASTER OT Detection
  15. GRB 160227A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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