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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. GRB 200922A: Chilescope optical observations
  2. GRB 200922A: chance superposition between optical afterglow and archival star
  3. GRB 200922A: Insight-HXMT/HE detection
  4. GRB 200922A: Swift-BAT refined analysis
  5. Improved enhanced Swift-XRT position of GRB 200922A
  6. GRB 200922A: Swift/UVOT Detection
  7. GRB 200922A: LCO observations
  8. Swift GRB 200922A: Global MASTER-Net observations report
  9. GRB 200922A: Swift-XRT refined Analysis
  10. GRB 200922A: Enhanced Swift-XRT position
  11. GRB 200922A: Swift detection of a burst with possible optical counterpart

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