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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.

Advanced Search Examples (click to copy):

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

23 results found.

  1. GRB 130420A: Continued Skynet/GORT Observations/Detections
  2. GRB 130420A: Continued RATIR Optical and NIR Observations
  3. GRB 130420A: ROTSE-III data analysis
  4. GRB 130420A: Continued RATIR Optical and NIR Observations
  5. GRB 130420A: Redshift from 10.4m GTC
  6. GRB 130420A: Early RAPTOR Simultaneous Multi-Color Observations
  7. GRB 130420A: Continued RATIR Optical and NIR Observations
  8. GRB 130420A: Fermi GBM observation
  9. GRB 130420A: ISON-NM optical observations
  10. Skynet/GORT observations of GRB130420A
  11. GRB 130420A: Swift/UVOT Detection
  12. GRB 130420A: Swift-XRT refined Analysis
  13. GRB 130420A, Swift-BAT refined analysis
  14. GRB 130420A: GMG optical observation
  15. GRB 130420A: Enhanced Swift-XRT position
  16. GRB130420A : Xinglong TNT optical upper limit
  17. GRB 130420A: Weihai Optical Observations
  18. GRB 130420A: T21 optical observations
  19. GRB 130420A: RATIR Optical and NIR Observations
  20. GRB 130420A: PAIRITEL NIR detections
  21. GRB 130420A: ROTSE-III Detection of Optical Counterpart
  22. GRB 130420A: Swift detection of a burst with an optical counterpart
  23. GRB 130420A: Faulkes Telescope North candidate

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