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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').

13 results found.

  1. GRB 200306C: Liverpool Telescope observations
  2. GRB 200303A: Fermi GBM observation
  3. GRB 200303A: Swift-XRT refined Analysis
  4. GRB 200303A: Swift-BAT refined analysis
  5. GRB 200303A: NOT optical observations
  6. GRB 200303A: Swift/UVOT Upper Limits
  7. GRB 200303A: FRAM-ORM optical limit
  8. GRB 200303A: GOTO observations upper limit
  9. GRB 200303A: Optical limit from CAHA
  10. GRB 200303A: CALET Gamma-Ray Burst Monitor detection
  11. GRB 200303A: Enhanced Swift-XRT position
  12. GRB 200303A: Swift detection of a burst
  13. GRB 200303A: Fermi GBM Final Real-time Localization

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