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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').

17 results found.

  1. GRB 231104A: VZLUSAT-2 detection
  2. GRB 231104A: Swift-BAT refined analysis
  3. GRB 231104A: FRAM-ORM optical limit
  4. GRB 231104A: Wendelstein Optical/Infrared Observations
  5. GRB 231104A: NuSTAR Observation of the prompt emission
  6. GRB 231104A: 3.6m DOT optical upper limit
  7. GRB 231104A: NOT upper limit
  8. GRB 231104A: Fermi GBM Observation
  9. GRB 231104A: AKO Upper Limit
  10. GRB 231104A: AstroSat CZTI detection
  11. GRB 231104A: Swift-XRT refined Analysis
  12. GRB 231104A: Fermi-LAT detection
  13. GRB 231104A: Swift/UVOT Upper Limits
  14. GRB 231104A: Enhanced Swift-XRT position
  15. GRB231104A: LCOGT Optical Upper Limits
  16. GRB 231104A: Swift detection of a bright burst
  17. GRB 231104A: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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