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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').

14 results found.

  1. GRB 100728A: GROND host detection and X-shooter redshift
  2. GRB 100728A: Suzaku WAM observation of the prompt emission
  3. Konus-Wind observation of GRB 100728A
  4. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  5. GRB 100728A, Swift-BAT refined analysis
  6. GRB 100728A: Swift/UVOT Upper Limits
  7. GRB 100728A: Swift-XRT refined analysis
  8. GRB 100728B: Skynet/PROMPT Detections (correction)
  9. GRB 100728B: KAIT optical afterglow detection (correction)
  10. GRB 100728A: Skynet/PROMPT Detections
  11. GRB 100728A: KAIT optical afterglow detection
  12. GRB 100728A: Fermi GBM observation
  13. GRB 100728A: Enhanced Swift-XRT position
  14. GRB 100728A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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