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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').

12 results found.

  1. GRB 190427A: CALET Gamma-Ray Burst Monitor detection
  2. GRB 190427A: Swift/UVOT Upper Limits
  3. GRB 190427A, Swift-BAT refined analysis
  4. GRB 190427A: Fermi GBM detection
  5. GRB 190427A: Lick/Nickel telescope optical observations
  6. GRB 190427A: MITSuME Akeno optical upper limits
  7. GRB 190427A: COATLI Optical Observations
  8. GRB 190427A: RATIR Optical and NIR Observations
  9. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  10. GRB 190427A: NOT optical observations
  11. GRB 190427A: Swift-XRT observations
  12. GRB 190427A: Swift detection of a short burst

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