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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 220412A: GRANDMA observations
  2. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  3. GRB 220412A: BOOTES-network optical upper limits
  4. GRB 220412A: Swift-BAT refined analysis
  5. GRB 220412A: RATIR Observations of the Fading Afterglow
  6. GRB 220412A: MITSuME Akeno optical upper limits
  7. Correction to GCN 31888: GRB 220412A: Swift-XRT refined Analysis
  8. GRB 220412A: Swift-XRT refined Analysis
  9. GRB 220412A: Enhanced Swift-XRT position
  10. GRB 220412A: Swift/UVOT Upper Limits
  11. GRB 220412A: RATIR Afterglow Candidate
  12. GRB 220412A: Swift detection of a burst

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