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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21 results found.

  1. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  2. GRB 201216C: VIRT optical observations
  3. Correction to GCN 29278: GRB 201216C XRT refined analysis
  4. GRB 201216C: Swift-XRT refined Analysis
  5. GRB 201216C: TSHAO, Terskol, Mondy optical upper limits
  6. GRB201216C: No significant detection in HAWC
  7. GRB 201216C: Liverpool Telescope First Hour Observations
  8. Konus-Wind detection of GRB 201216C
  9. GRB 201216C: Swift-BAT refined analysis
  10. GRB 201216C: VLT X-shooter spectroscopy and potential high redshift of a VHE-emitting GRB
  11. GRB 201216C: Fermi-LAT upper limit
  12. GRB 201216C: MAGIC detection in very high energy gamma rays
  13. GRB 201216C: AstroSat CZTI detection
  14. GRB 201216C: Fermi GBM detection
  15. GRB 201216C: Swift/UVOT Upper Limits
  16. GRB 201216C: FRAM-ORM afterglow confirmation
  17. GRB 201216C: Enhanced Swift-XRT position
  18. GRB 201216C: VLT afterglow candidate discovery
  19. GRB 201216C: Swift-XRT observations
  20. GRB 201216C: Fermi GBM Final Real-time Localization
  21. GRB 201216C: Swift detection of a burst

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Download all Circulars as a .tar.gz archive:
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