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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').

13 results found.

  1. GRB 181020A: AstroSat CZTI detection
  2. Konus-Wind observation of GRB 181020A
  3. GRB 181020A: REM detection
  4. GRB 181020A: Swift/UVOT Detection
  5. GRB 181020A: Global MASTER Net OT observations
  6. GRB 181020A: LCO Cerro Tololo observations
  7. GRB 181020A: Swift-BAT refined analysis
  8. GRB 181020A: VLT/X-shooter spectroscopy and redshift
  9. GRB 181020A: Swift-XRT refined Analysis
  10. GRB 181020A: Fermi GBM detection
  11. GRB 181020A: Enhanced Swift-XRT position
  12. GRB 181020A: Fermi-LAT detection
  13. GRB 181020A: Swift detection of a burst with an optical counterpart


Download all Circulars as a .tar.gz archive:
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