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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"

31731 results found.

  1. GRB 980425 optical observations
  2. GRB980326, optical observations
  3. GRB980326, optical observations
  4. GRB980329, Fading IR counterpart to radio source
  5. GRByymmdd, Announcement of automation
  6. GRB980326 IPN annulus
  7. GRB980329
  8. GRB980329 Keck K-band observations
  9. GRB980329 sub-millimeter observations
  10. GRB980329 IPN annulus
  11. GRB980329 optical observations
  12. GRB980329 near-IR observations
  13. GRB980329 optical observations
  14. GRB980326 optical observations
  15. GRB980326 optical observations
  16. GRB970508 SAO RAS optical observations
  17. GRB 971214: Redshift from Keck Observations
  18. Near-IR follow-up on GRB 971227
  19. GRB971214: Keck R & I-band Observations
  20. GRB 971227: Optical Observations
  21. Optical Observations of the GRB 971227 field
  22. GRB971227: Plaskett R-band observations
  23. GRB 971227: Optical clarifications
  24. GRB971227: LOTIS observations
  25. GRB971214: Optical Observations and Calibrations
  26. Optical Observations of GRB 971214 at Keck
  27. GRB 971024: Refined analysis by USNOFS Observations
  28. GRB 971024: USNO Observations
  29. GRB 970925: BATSE Localization
  30. IRAS 18119-1342 and the possible new SGR
  31. GRB 970228: Keck/LRIS Optical Observations

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