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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"

17420 results found.

  1. GRB000210: possible afterglow detection with BeppoSAX NFI
  2. GRB000201, Radio Observations
  3. GRB000210: BeppoSAX GRBM and WFC Detection
  4. GRB000201 Optical Observations
  5. GRB 000126, optical observations
  6. IPN localization of GRB000126
  7. IPN annulus for GRB000115
  8. GRB991216, UBVRIJHK field photometry
  9. GCN resumes full operations
  10. GRB 991216: Detection of the Host and/or Absorber Galaxy
  11. GRB 991216 RXTE ASM Observations
  12. GRB 991217 (SAX J2303.2+0015) Optical observations
  13. Chandra observation of the X-ray afterglow of GRB991216
  14. SAX J2303.2+0015 Optical observations
  15. IR observations of GRB991216
  16. GRB 991217 (SAX J2303.2+0015) Optical observations
  17. GRB 991216 Radio Observations
  18. GRB 991208 Infrared Detection
  19. GRB991216
  20. GRB 991216--Summary of RXTE Observations
  21. GRB 991216 Optical Observations
  22. GRB 991216, optical observations
  23. GRB 991208 SAO-RAS Spectroscopy
  24. SAX J2303.2+0015: an x-ray/GRB?
  25. GRB 991216, Optical Transient
  26. GRB991216 ('Beethoven Burst') B, R, and K Observations
  27. GRB991216, infrared observations
  28. GRB 991208 optical observations
  29. GRB 991216 Optical Observation
  30. GRB 991216: Extremely bright BATSE burst
  31. R-band Observations of GRB991208 at TNG
  32. GRB991208, optical observations
  33. GRB 991208, Optical Observation
  34. GRB991208, optical observations
  35. IPN localization of GRB991208
  36. Optical Observations of GRB991105
  37. GRB991106: BeppoSAX/BATSE results
  38. BeppoSAX NFI Observation of GRB991106
  39. GRB 991106, radio observations
  40. GRB991106: the first BeppoSAX short GRB detection?
  41. GRB 991106 Optical Observations
  42. GRB991106, optical observation at SAO-RAS
  43. GRB 991106, LOTIS Optical Observations
  44. GRB991105: SAX-GRBM/-WFC detection
  45. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  46. GRB 991014, Optical Observations
  47. GRB 991014 - BeppoSAX NFI observations
  48. GRB 991014, radio observations
  49. GRB 991014, Optical Observations
  50. GRB 991014, optical observations
  51. Optical Observations of GRB990907
  52. GRB990907: BeppoSAX follow up and X-ray afterglow
  53. GRB990907 and 990908
  54. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  55. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  56. GRB990806 BeppoSAX follow up
  57. GRB 990806 Optical observations
  58. GRB 990806, optical observations
  59. GRB 990806, Optical Observations
  60. GRB990806: possible X-ray afterglow, BeppoSAX
  61. GRB 990712 Optical Observations
  62. GRB 990712
  63. Late-time HST/STIS Observations of GRB 990510
  64. BeppoSAX NFI Observation of GRB990705
  65. BeppoSAX NFI Observation of GRB990705
  66. GRB 990705, R-band observations
  67. GRB990704: SAX-NFI results summary
  68. GRB990704 radio and optical observations
  69. GRB990704
  70. GRB990704, optical observations
  71. GRB990704: possible X-ray afterglow
  72. GRB990704
  73. GRB990704: BeppoSAX detection
  74. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  75. GRB 990627, radio observations
  76. Late-time HST/STIS Observation of GRB 990123
  77. Optical Observations of GRB 990506
  78. GRB 990506 Radio Transient
  79. GRB990527 Optical Observations
  80. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  81. IPN error box for GRB990527
  82. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  83. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  84. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  85. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  86. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  87. radio observations of X-ray/GRB transient field
  88. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  89. Optical report on X-ray/GRB transient
  90. radio detection of X-ray/GRB transient
  91. GRB 990510: optical linear polarization
  92. GRB 990510: optical observations
  93. GRB990510: X-ray afterglow
  94. GRB 990510 optical observations
  95. GRB990510: NFI X-ray source
  96. GRB 990506 Radio Observations
  97. GRB 990123, optical monitoring
  98. GRB 990506, optical observations
  99. GRB 990510: Final BeppoSAX-WFC Coordinates
  100. GRB 990506, Optical Observations

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