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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').

11 results found.

  1. GRID detection of GRB 231230A
  2. GRB 231230A: Swift-BAT refined analysis
  3. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 231230A: Swift-XRT refined Analysis
  5. GRB 231230A: GOTO optical upper limits
  6. GRB 231230A: Enhanced Swift-XRT position
  7. GRB 231230A: Swift/UVOT Upper Limits
  8. GRB 231230A: NOT optical upper limits
  9. GRB 231230A: Prompt enhanced Swift-XRT position
  10. GRB 231230A: Swift detection of a burst
  11. GRB 231230A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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