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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"

18020 results found.

  1. GRB 991208 SAO-RAS Spectroscopy
  2. SAX J2303.2+0015: an x-ray/GRB?
  3. GRB 991216, Optical Transient
  4. GRB991216 ('Beethoven Burst') B, R, and K Observations
  5. GRB991216, infrared observations
  6. GRB 991208 optical observations
  7. GRB 991216 Optical Observation
  8. GRB 991208 Keck Spectroscopy
  9. GRB 991216: Extremely bright BATSE burst
  10. GRB991208, optical observations
  11. GRB 991208, Optical Observation
  12. GRB991208, optical observations
  13. GRB 991208 Optical Decay
  14. IPN localization of GRB991208
  15. Optical Observations of GRB991105
  16. GRB991106: BeppoSAX/BATSE results
  17. BeppoSAX NFI Observation of GRB991106
  18. GRB 991106, radio observations
  19. GRB991106: the first BeppoSAX short GRB detection?
  20. GRB 991106 Optical Observations
  21. GRB991106, optical observation at SAO-RAS
  22. GRB 991106, LOTIS Optical Observations
  23. BeppoSAX GRB Alert: GRB991106
  24. GRB991105: SAX-GRBM/-WFC detection
  25. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  26. GRB 991014, Optical Observations
  27. GRB 991014 - BeppoSAX NFI observations
  28. GRB 991014, radio observations
  29. GRB 991014, Optical Observations
  30. GRB 991014, optical observations
  31. Optical Observations of GRB990907
  32. GRB990907: BeppoSAX follow up and X-ray afterglow
  33. GRB990907 and 990908
  34. GRB 990712 Late Optical Decay and Host Galaxy
  35. GRB 990712, Optical Observation
  36. GRB990806 BeppoSAX follow up
  37. GRB 990806 Optical observations
  38. GRB 990806, optical observations
  39. GRB 990806, Optical Observations
  40. GRB 990712 Optical Observations
  41. GRB 990712
  42. Late-time HST/STIS Observations of GRB 990510
  43. BeppoSAX NFI Observation of GRB990705
  44. BeppoSAX NFI Observation of GRB990705
  45. GRB 990705, R-band observations
  46. GRB990704: SAX-NFI results summary
  47. GRB990704 radio and optical observations
  48. GRB990704
  49. GRB990704, optical observations
  50. GRB990704
  51. Refined BeppoSAX-WFC position of GRB990704
  52. GRB990704: BeppoSAX detection
  53. Late-time HST/STIS Observation of GRB 990123
  54. Optical Observations of GRB 990506
  55. GRB990527 Optical Observations
  56. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  57. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  58. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. radio observations of X-ray/GRB transient field
  63. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  64. Optical report on X-ray/GRB transient
  65. GRB 990510: optical linear polarization
  66. GRB 990510: optical observations
  67. GRB990510, VI observations
  68. GRB 990510: Broad Band Break
  69. GRB 990510: BATSE Observations
  70. GRB 990510 optical observations
  71. IPN localization of GRB990510
  72. GRB 990506 Radio Observations
  73. GRB 990123, optical monitoring
  74. GRB 990506: BATSE Observations
  75. GRB 990506, optical observations
  76. GRB 990506, Optical Observations
  77. GRB 990506 optical observations
  78. GRB 990506, optical observations
  79. GRB 990506, optical observations from +1 to +3 hours
  80. GRB 990506, optical observations
  81. GRB990506 observation plan
  82. IPN localization for GRB990506
  83. GRB 990316 Optical Observations
  84. GRB990316, Optical observations
  85. GRB 990316 optical observations
  86. GRB990316: simultaneous optical observation
  87. ASM/IPN error box for GRB 990308 (BATSE #7457)
  88. GRB990308, Possible new SGR~0209+70
  89. GRB 990123, Field Photometry
  90. GRB 990217 Optical Observations
  91. BATSE Flight Anomaly
  92. GRB990123 observations
  93. GRB990123, Optical Observation
  94. GRB 990123: Discovery of the Probable Host Galaxy
  95. GRB19990123 observations
  96. GRB 990123: BVRI standards in the field
  97. GRB 990123: Updated Keck Spectroscopy Results
  98. GRB981220, field photometry
  99. GRB990123, Optical observation
  100. GRB990123, 15-GHz limits

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