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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"

24950 results found.

  1. GRB971214 Secondary Standards
  2. GRB980519 Secondary Standards
  3. BATSE on-board GRB trigger change
  4. GRB 980519 Optical Observations
  5. GRB 980519
  6. GRB980519 optical observations
  7. GRB 980519 Optical Observations
  8. GRB980519 BATSE Observations
  9. GRB980519 Optical Observations
  10. GRB980519 Optical Observations
  11. GRB 980519 Optical Observations
  12. GRB980515, BeppoSAX IAUC to be submitted
  13. BSAX Observations of GRB980425 field
  14. IPN web site of GRBs
  15. GRB980425 BATSE observations
  16. SAX J0840.7+2248 Optical Observations
  17. GRB980425: optical obs.
  18. GRB980425: Radio Observations
  19. report on BSAX observations of GRB980425
  20. GRB 980329 ROSAT observation
  21. GRB980326 X-ray Observations
  22. GRB980326, optical observations
  23. GRB980326, optical observations
  24. GRB980329, Fading IR counterpart to radio source
  25. GRB980329 Keck K-band observations
  26. GRB980329 sub-millimeter observations
  27. GRB980329 optical observations
  28. GRB980329 near-IR observations
  29. GRB980329 near-IR observations
  30. GRB980326 optical observations
  31. GRB980329 optical observations
  32. GRB980329 VLA observations
  33. GRB980329 optical observations
  34. GRB980329 optical observations
  35. GRB980326 optical observations
  36. GRB980326 optical observations
  37. Optical Observations of GRB 970508
  38. Near-IR follow-up on GRB 971227
  39. Optical Observations of the GRB 971227 field
  40. Optical Observations on GRB 971227
  41. GRB971227: Plaskett R-band observations
  42. GRB 971227: Optical clarifications
  43. GRB971227: Further CAHA R-band images
  44. GRB971227: LOTIS observations
  45. GRB971214: Optical Observations and Calibrations
  46. GRB 971214: Optical Observations
  47. Radio Observations of GRB 971214 at the VLA
  48. GRB 971024: Refined analysis by USNOFS Observations
  49. GRB 971024: KPNO Optical Observations
  50. GRB 970828: Palomar Observations

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