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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"

24928 results found.

  1. GRB980326, optical observations
  2. GRB980329, Fading IR counterpart to radio source
  3. GRB980329 Keck K-band observations
  4. GRB980329 sub-millimeter observations
  5. GRB980329 optical observations
  6. GRB980329 near-IR observations
  7. GRB980329 near-IR observations
  8. GRB980326 optical observations
  9. GRB980329 optical observations
  10. GRB980329 VLA observations
  11. GRB980329 optical observations
  12. GRB980329 optical observations
  13. GRB980326 optical observations
  14. GRB980326 optical observations
  15. Optical Observations of GRB 970508
  16. Near-IR follow-up on GRB 971227
  17. Optical Observations of the GRB 971227 field
  18. Optical Observations on GRB 971227
  19. GRB971227: Plaskett R-band observations
  20. GRB 971227: Optical clarifications
  21. GRB971227: Further CAHA R-band images
  22. GRB971227: LOTIS observations
  23. GRB971214: Optical Observations and Calibrations
  24. GRB 971214: Optical Observations
  25. Radio Observations of GRB 971214 at the VLA
  26. GRB 971024: Refined analysis by USNOFS Observations
  27. GRB 971024: KPNO Optical Observations
  28. GRB 970828: Palomar Observations

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