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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24316 results found.

  1. GRB020321: a faint BeppoSAX detection
  2. GRB020317, optical observations
  3. GRB020305, optical observations
  4. GRB020124, optical observations
  5. HETE 1896: Optical observations
  6. GRB011130 (=XRF011130), Optical Observations
  7. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  8. GRB 011030: K-band observations
  9. The X-ray Flash 011030 ('GRB 011030')
  10. GRB 011019 optical observation
  11. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  12. GRB 010921: The afterglow of HETE #1761
  13. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  14. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  15. GRB010921 Optical Observations
  16. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  17. HETE Trigger #1760 (GRB 010920B?): a new optical source
  18. HETE Trigger #1759 (GRB 010920?) optical observations
  19. BeppoSAX/GRBM detection of GRB 010801
  20. GCN and HETE status
  21. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  22. GRB 010629 Optical Observations
  23. IPN triangulation of GRB010613
  24. IPN triangulation of GRB010612
  25. GRB010518: a faint BeppoSAX detection
  26. GRB010324: BeppoSAX/GRBM data
  27. GRB 010214: X-Ray afterglow
  28. GRB010213, optical observations
  29. GRB010126: CONCAM crude optical limits during GRB
  30. HETE positions added to GCN
  31. CONCAM null result on GRB001005
  32. CONCAM crude optical limits before and after GRB000926
  33. GRB000607, optical observations
  34. GRB 000615: NIR observations
  35. IPN triangulation of GRB000519
  36. RXTE/ASM and IPN localization of GRB 000508B
  37. BeppoSAX GRB000424
  38. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  39. GRB000408, lotis optical observations
  40. GRB 000313 - optical transient in the BATSE error box
  41. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  42. BATSE GRB trigger criterion changed
  43. GRB000210 X-ray afterglow
  44. GRB 000210: BATSE Observations
  45. GRB000201 Optical Observations
  46. GRB 000201: TAROT optical observations
  47. BATSE GRB trigger criteria changed
  48. BATSE+IPN location of GRB000131
  49. BATSE location of GRB000126
  50. BATSE Observations of GRB000115
  51. Second RXTE Observation of GRB 000115
  52. Single IPN error box for GRB991229
  53. GRB 991216: Updated BATSE parameters
  54. GRB 991216--Summary of RXTE Observations
  55. GRB 991216: Extremely bright BATSE burst
  56. GRB991106: BeppoSAX/BATSE results
  57. BeppoSAX NFI Observation of GRB991106
  58. GRB 991105: BATSE Observations
  59. GRB991106, optical observation at SAO-RAS
  60. GRB 991106, LOTIS Optical Observations
  61. GRB991105: SAX-GRBM/-WFC detection
  62. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  63. GRB ALERT: GRB991105
  64. GRB 991014 - BeppoSAX NFI observations
  65. GRB991014 BATSE Observations
  66. Super-LOTIS optical observation of GRB991014
  67. BeppoSAX ALERT: GRB991014
  68. GRB 990915 optical observations
  69. BATSE GRB trigger criteria
  70. IPN error box for GRB990915 (=BATSE 7766)
  71. IPN localization of BATSE #7766 (GRB990915)
  72. GRB990806: BATSE Observations
  73. BeppoSAX ALERT GRB990806: Summer GRB
  74. BeppoSAX NFI Observation of GRB990705
  75. BeppoSAX NFI Observation of GRB990705
  76. GRB990704
  77. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  78. BeppoSAX: GRB990625
  79. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  80. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  81. BeppoSAX: A new fast X-ray transient
  82. GRB990510: X-ray afterglow
  83. GRB 990510: BATSE Observations
  84. GRB 990506: BATSE Observations
  85. GRB990323 PRECISE IPN POSITION
  86. GRB990316: simultaneous optical observation
  87. GRB990316 - Optical null results
  88. ASM/IPN error box for GRB 990308 (BATSE #7457)
  89. GRB 990308a and GRB 990308b
  90. BATSE Resumes Normal Operations
  91. Search for Potential Images of GRB 990123
  92. Search for Potential Images of GRB 990123
  93. GRB990123, OSSE observations
  94. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  95. GRB 990123: BATSE Observations
  96. GRB990123, early optical counterpart detection
  97. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  98. Possible identification of SN1999E with GRB980910
  99. GRB 980923 BATSE Observations
  100. GRB980703 - BeppoSAX/GRBM detection

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