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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"

10364 results found.

  1. SGR1806-20: A Second, Intense Burst Localized by HETE
  2. SGR1806-20: Localization by HETE
  3. X-ray precursors to the large flare from SGR 1900+14
  4. GRB010427, Gamma Ray Observations
  5. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  6. SGR 1900+14, Chandra observations
  7. GRB010326: Localization by HETE
  8. GRB010214, field photometry
  9. GRB010222, field photometry
  10. GRB010214B,Gamma Ray Observations
  11. BeppoSAX ALERT: GRB010220
  12. GRB010214: BeppoSAX WFC and GRBM preliminary data
  13. GRB 010214, Optical Observations
  14. J-Band Observation of GRB 010214.
  15. Possible InfraRed Transient of GRB 010214.
  16. GRB010214 Optical Observation
  17. GRB 010214, optical observations
  18. HETE Status
  19. GRB010126 opt. obs.
  20. IPN/RXTE TRIANGULATION OF GRB010126
  21. GRB010126 optical observations
  22. IPN/RXTE TRIANGULATION OF GRB010126
  23. IPN TRIANGULATION OF GRB010115
  24. IPN triangulation of GRB001219
  25. GRB 001212 optical observation
  26. IPN triangulation of GRB001120
  27. GRB 001109 X-ray afterglow with BeppoSAX
  28. GRB001109: Optical observations
  29. GRB001109: BeppoSAX/NFI Observations
  30. XMM-Newton observation of GRB001025
  31. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  32. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  33. ASM Localization of GRB 001025
  34. GRB001018, Gamma Ray Observations
  35. IPN TRIANGULATION OF GRB001019
  36. GRB 000926 Chandra Observation
  37. IPN triangulation of GRB 001004
  38. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  39. GRB000926 K'-band Observation
  40. IPN triangulation of GRB000925
  41. IPN triangulation of GRB000910
  42. IPN triangulation of GRB000830
  43. HST/STIS observations of the host galaxy of GRB 980329
  44. SGR 1806-20 burst activity
  45. GRB000801 & GRB000730, Gamma Ray Observations
  46. GRB000730, Gamma Ray Observations
  47. GRB000801, Gamma Ray Observations
  48. possible optical counterpart of GRB 000630
  49. IPN triangulation of GRB000630
  50. GRB 000623, optical observations
  51. GRB000620, optical observations
  52. GRB000620: BeppoSAX WFC and GRBM detection
  53. BeppoSAX ALERT: GRB000620
  54. GRB000620: BeppoSAX Alert
  55. GRB000616 [IPN Position]
  56. GRB000615B [IPN Position]
  57. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  58. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  59. GRB000519: Optical observations
  60. IPN triangulation of GRB000516
  61. GRB 000429, optical observation
  62. GRB 000418, UBVRI field photometry
  63. GRB 000418, Optical Observation
  64. GRB 000418, optical observation
  65. GRB 000418, Optical Observation
  66. GRB 000418, Optical Observation
  67. GRB000418, near-infrared observations
  68. IPN error box for GRB000418
  69. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  70. GRB 000408, optical observations
  71. GRB000313, Radio observations
  72. GRB000301C - B and R photometry
  73. GRB 000307, BVRI Field Photometry
  74. IPN error box for GRB000307
  75. GRB 000301C, UBVRI field photometry
  76. GRB 000301C, Optical Observation
  77. GRB 000301A, Radio Observations
  78. GRB 000301C : Optical Candidate
  79. GRB000226 [IPN Position]
  80. GRB 000115 Optical observations
  81. BATSE GRB trigger criterion changed
  82. GRB 000210: BATSE Observations
  83. GRB000210: BeppoSAX GRBM and WFC Detection
  84. GRB000201 Optical Observations
  85. BATSE Observations of GRB000115
  86. GCN resumes full operations
  87. Chandra observation of the X-ray afterglow of GRB991216
  88. GRB 991216 Optical spectroscopy/imaging
  89. GRB 991216 Optical Observation
  90. GRB 991216: Extremely bright BATSE burst
  91. IPN localization of GRB991208
  92. GRB 991105: BATSE Observations
  93. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  94. GRB 990915 optical observations
  95. BATSE GRB trigger criteria
  96. GRB990907: BeppoSAX follow up and X-ray afterglow
  97. GRB990806: BATSE Observations
  98. GRB 990705, R-band observations
  99. Infrared and Optical Observations of GRB990705
  100. GRB990704

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