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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').

15 results found.

  1. GRB 230805B: Swift-BAT refined analysis
  2. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  3. GRB 230805B: AstroSat CZTI detection
  4. GRB 230805B : MITSuME Akeno optical upper limits
  5. GRB 230805B: Fermi GBM observation
  6. GRB 230805B : OHP/T193 optical upper limit
  7. GRB 230805B: Enhanced Swift-XRT position
  8. GRB 230805B: Swift/UVOT Upper Limits
  9. GRB 230805B: Bassano Bresciano observatory upper limit
  10. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  11. GRB 230805B: NOT optical afterglow confirmation
  12. GRB 230805B: Swift-XRT refined Analysis
  13. GRB 230805B: SAO RAS optical observations
  14. Swift GRB 230805B: Global MASTER-Net observations report
  15. GRB 230805B: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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