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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"

16757 results found.

  1. GRB980519, Optical Observations
  2. GRB980703 optical photometry
  3. GRB980703 optical observations
  4. GRB980703 Transient Optical Follow-Up
  5. GRB980703: LOTIS observation at early times
  6. BeppoSAX NFI observations of GRB 980703
  7. GRB 980703: ASM Position & Intensity
  8. GRB980703 optical followup
  9. Radio observations of SGRs
  10. SGR1900+14 field optical observations
  11. GRB 980613: Optical transient and its host galaxy
  12. GRB 980613: Detection of the probable host galaxy
  13. GRB 980613 Optical Observations
  14. GRB 980613 optical observations
  15. Discovery of a new SGR source, SGR1627-41
  16. GRB980613 Optical Observations
  17. GRB980613 observations from Palomar
  18. GRB980613 BeppoSAX-NFI follow up
  19. GRB980613 Near Infra-Red Observations
  20. GRB971214 Secondary Standards
  21. GRB980519 Secondary Standards
  22. GRB 980519 Optical Observations
  23. GRB 980519
  24. GRB980519 optical observations
  25. GRB 980519 Optical Observations
  26. GRB970519, optical follow-up at Schmidt Calern
  27. GRB980519 Optical Observations
  28. GRB 980519 Optical Observations
  29. GRB980515, BeppoSAX IAUC to be submitted
  30. BSAX Observations of GRB980425 field
  31. SAX J0840.7+2248 Optical Observations
  32. GRB980425: optical obs.
  33. GRB980425: Radio Observations
  34. report on BSAX observations of GRB980425
  35. GRB 980329 ROSAT observation
  36. GRB980326 X-ray Observations
  37. GRB980326, optical observations
  38. GRB980326, optical observations
  39. GRB980329 Keck K-band observations
  40. GRB980326 optical observations
  41. GRB980329 optical observations
  42. GRB980329 VLA observations
  43. GRB980329 optical observations
  44. GRB980326 optical observations
  45. Optical Observations of GRB 970508
  46. Near-IR follow-up on GRB 971227
  47. Optical Observations of the GRB 971227 field
  48. Optical Observations on GRB 971227
  49. GRB971227: Plaskett R-band observations
  50. GRB 971227: Optical clarifications
  51. GRB971227: Further CAHA R-band images
  52. GRB971227: LOTIS observations
  53. GRB971214: Optical Observations and Calibrations
  54. GRB 971214: Optical Observations
  55. Radio Observations of GRB 971214 at the VLA
  56. GRB 971024: KPNO Optical Observations
  57. GRB 970828: Palomar Observations

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