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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').

16 results found.

  1. GRB 221216A: Swift-BAT refined analysis
  2. IceCube-221216A: No Candidate Counterparts from the Zwicky Transient Facility
  3. GRB 221216A: Detection by VZLUSAT-2
  4. Fermi-LAT gamma-ray observations of IceCube-221216A
  5. IceCube-221216A: Upper limits from a search for additional neutrino events in IceCube
  6. GRB 221216A: Swift/UVOT Upper Limits
  7. GRB 221216A: Fermi GBM observation
  8. GRB 221216A: Swift-XRT refined Analysis
  9. GRB 221216A: AKO Upper Limit
  10. GRB 221216A: Enhanced Swift-XRT position
  11. Swift GRB 221216A: Global MASTER-Net observations report
  12. GRB 221216A: Zadko observatory - Gingin optical observations
  13. GRB 221216A: Nanshan/NEXT optical upper limits
  14. GRB 221216A: Swift detection of a burst
  15. GRB 221216A: Fermi GBM Final Real-time Localization
  16. IceCube-221216A - IceCube observation of a high-energy neutrino candidate track-like event


Download all Circulars as a .tar.gz archive:
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