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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"

364 results found.

  1. GRB 991217
  2. SAX J2303.2+0015: an x-ray/GRB?
  3. BeppoSAX NFI Observation of GRB991106
  4. GRB 991105: BATSE Observations
  5. BeppoSAX refined position for GRB991106
  6. GRB991105: SAX-GRBM/-WFC detection
  7. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  8. GRB ALERT: GRB991105
  9. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  10. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  11. GRB990806 BeppoSAX follow up
  12. GRB 990712
  13. Infrared and Optical Observations of GRB990705
  14. GRB990704: SAX-NFI results summary
  15. GRB 990704 X-ray Observations
  16. GRB990705: Intriguing Positional Coincidences
  17. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  18. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  19. Optical report on X-ray/GRB transient
  20. BeppoSAX: A new fast X-ray transient
  21. GRB981220 VLBA observations
  22. GRB981220, IPN localization
  23. GRB 981220, radio observations
  24. GRB990123, Probability of gravitational lensing
  25. GRB990123 IPN annulus
  26. GRB990123, refined SAX-WFC position
  27. GRB 990123, Radio observations
  28. Optical Observations of GRB 981220
  29. GRB981220
  30. GRB981220, Optical Observations
  31. GRB 981220 Optical observations
  32. GRB 981226 Optical Observations
  33. GRB981220, sub-millimeter observations
  34. GRB 981220 and GRB 981226, optical observations
  35. GRB981226 BeppoSAX follow up
  36. GRB981220 B, R and I band observations
  37. GRB 981220:Optical Observations
  38. GRB 981220
  39. GRB980425: X-ray revised positions
  40. GRB980519, Optical Observations
  41. GRB980703, Host galaxy multicolor photometry
  42. GRB 980703 (NFI observations)
  43. BeppoSAX NFI observations of GRB 980703
  44. GRB980703
  45. GRB980613, optical observations
  46. GRB 980613 Optical Observations
  47. GRB980613 BeppoSAX-NFI follow up
  48. GRB980613, BeppoSAX WFC positions
  49. GRB980519 IPN POSITION
  50. GRB980515: SAX-WFC updated position
  51. BSAX Observations of GRB980425 field
  52. GRB980425 BATSE observations
  53. SAX J0840.7+2248 Optical Observations
  54. report on BSAX observations of GRB980425
  55. GRB980329 IPN annulus
  56. GRB980329 near-IR observations
  57. GRB980329 near-IR observations
  58. GRB980329 near IR observations
  59. GRB980329 optical observations
  60. Optical Observations for GRB 971227
  61. GRB 971227: Optical observations
  62. GRB971214: Optical Observations and Calibrations
  63. Optical Observations of GRB 971214 at Keck
  64. GRB 971214: USNOFS Observations Summary

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