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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"

29 results found.

  1. GRB 150413A: AMI 15 GHz confirmation of radio counterpart
  2. GRB 150413A: CrAO optical observations
  3. GRB 150413A: Konus-Wind and Swift/BAT joint spectral analysis
  4. GRB 150413A: Swift-XRT observations
  5. GRB 150413A: RTT150 optical observations
  6. GRB 150413A: ISON-Ussuriysk optical observations
  7. GRB 150413A: MITSuME Akeno Optical observation
  8. GRB 150413A: SAO RAS observations
  9. LOAO B, R Observations of GRB150413A
  10. GRB 150413A: Refined redshift
  11. GRB 150413A: GMG observation
  12. GRB 150413A: AMI 15 GHz detection of possible radio counterpart
  13. GRB 150413A: additional P60 observations
  14. GRB 150413A : Virtual Telescope optical observations
  15. GRB 150413A
  16. GRB 150413A: Bassano Bresciano Observatory optical observations
  17. GRB 150413A: T7 and T18 optical observations
  18. GRB 150413A: Swift-BAT refined analysis
  19. GRB 150413A: optical observations
  20. GRB 150413A: redshift determination with the 2.2m CAHA
  21. GRB 150413A: P60 photometry
  22. GRB 150413A: Khureltogot optical observations
  23. GRB 150413A: Tautenburg observations
  24. GRB 150413A: Nanshan optical and radio follow-ups
  25. GRB 150413A: Khureltogot optical observations
  26. GRB 150413A: MAXI/GSC detection
  27. GRB 150413A: MASTER very bright unusual OT observations
  28. GRB 150413A: MASTER bright OT detection
  29. GRB 150413A: Swift detection of a burst

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