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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"

232 results found.

  1. GRB000424, UBVRI field photometry
  2. GRB000418, UBVRI field photometry update
  3. GRB 000429, optical observation
  4. GRB 000429, UBVRI field photometry
  5. GRB 000418, UBVRI field photometry
  6. GRB 000418, optical observation
  7. GRB 000408, optical observations
  8. GRB 991208, UBVRI field photometry
  9. GRB 000323, optical observations
  10. GRB 000313 - optical transient in the BATSE error box
  11. GRB 000307, BVRI Field Photometry
  12. GRB 000301C, UBVRI field photometry
  13. GRB 000115, BVRI field photometry
  14. GRB991216, UBVRIJHK field photometry
  15. GRB 991217 (SAX J2303.2+0015) Optical observations
  16. GRB 991217
  17. GRB 991216, Optical Transient
  18. GRB 991014, optical observations
  19. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  20. GRB 990123, optical monitoring
  21. GRB 990506, optical observations
  22. GRB 990506, optical observations
  23. GRB 990123, Field Photometry
  24. GRB981220, field photometry
  25. GRB980703 H-band Observations
  26. GRB 980703 H-band Observations
  27. SGR1900+14 field optical observations
  28. GRB971214 Secondary Standards
  29. GRB980519 Secondary Standards
  30. GRB971214: Optical Observations and Calibrations
  31. GRB 971214: USNOFS Observations Summary
  32. Possible new SGR from US Naval Observatory

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