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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').

14 results found.

  1. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  2. IceCube-220907A: No significant detection in HAWC
  3. IceCube-220907A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 220907A: Swift-BAT refined analysis
  5. IceCube-220907A: One Candidate Counterpart from the Zwicky Transient Facility
  6. GRB 220907A: Fermi GBM observation
  7. GRB 220907A: Nanshan/NEXT optical upper limits
  8. GRB 220907A: Swift/UVOT Upper Limits
  9. GRB 220907A: Swift-XRT refined Analysis
  10. Fermi-LAT Gamma-ray Observations of IceCube-220907A
  11. GRB 220907A: Swift-XRT position
  12. GRB 220907A: Swift detection of a burst
  13. GRB 220907A: Fermi GBM Final Real-time Localization
  14. IceCube-220907A - IceCube observation of a high-energy neutrino candidate track-like event


Download all Circulars as a .tar.gz archive:
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