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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. GRB 091010: Fermi GBM observation
  2. GRB 091010: Faulkes Telescope North observations
  3. GRB 090531A: Skynet/PROMPT Observations
  4. GRB 090530A: Skynet/DSO Detections
  5. GRB 091010: RXTE detection
  6. Konus-Wind observations of GRB 091010
  7. GRB 091010: Enhanced XRT position
  8. GRB 091010 optical upper limits
  9. Detection of a short GRB 090929A by RT-2 Experiment
  10. RT-2 observation of the bright GRB 090926A
  11. GRB 091010: GROND afterglow candidate
  12. GRB 091010: Swift/UVOT Upper Limits
  13. GRB 091010: Swift-XRT position
  14. SuperAGILE GRB is 091010 and not 090910
  15. GRB 090910: SuperAGILE Localization of a Long GRB
  16. GRB 090926A: Skynet/PROMPT Observations of Day 6 - 11 Fading
  17. GRB 090518: Skynet/PROMPT Observations
  18. Short-Duration GRB 090621: Skynet/Dolomiti Observations
  19. GRB 090904A: afterglow confirmation
  20. GRB 090812: Skynet/PROMPT and GORT Observations
  21. GRB 091003A: Suzaku WAM observation of the prompt emission
  22. GRB 091003: Lick observations and possible SDSS host galaxy
  23. GRB 090926B: Skynet/PROMPT Observations
  24. GRB 091003: WHT ACAM observations
  25. Konus-Wind observation of GRB 091003A
  26. GRB 090929B: Suzaku WAM observation of the prompt emission
  27. GRB 090929A: Suzaku WAM observation of the prompt emission
  28. GRB 091003: Swift-XRT confirmation of fading afterglow
  29. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  30. GRB 091003: Skynet/DSO Observations
  31. GRB 091003: UVOT-enhanced XRT position
  32. GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
  33. GRB 091003: Swift XRT analysis
  34. GRB 091003A: Fermi LAT detection
  35. GRB 090926A: Skynet/PROMPT Observations of Day 4 - 6 Fading Rate
  36. GRB 091003A: Fermi GBM detection
  37. GRB 090926A: Skynet/PROMPT Observations of Post-Peak Fading
  38. GRB 090929A: Swift/UVOT Observations
  39. GRB 090929A, Swift-BAT refined analysis
  40. GRB 090929B, Swift-BAT refined analysis
  41. Trigger 371210: Swift/BAT Triggered on IGR J17511-3057
  42. GRB 090929A: Swift-XRT non-detection
  43. Konus-Wind observation of GRB 090929A
  44. Konus-Wind observation of GRB 090929B
  45. GRB 090927: Fermi GBM observation
  46. GRB 090929B: Swift-XRT refined analysis
  47. GRB 090926A: Fermi LAT and GBM refined analysis
  48. GRB 090929B: Gemini-N upper limits
  49. GRB 090929B: Skynet/DSO Observations
  50. GRB 090929B: Swift/UVOT Observations
  51. Konus-RF observation of GRB 090929A
  52. GRB 090929B: RAPTOR Discovery of Optical Counterpart
  53. GRB 090929A BAT location of the Fermi GBM burst
  54. Correction: GRB 090929B: Enhanced Swift-XRT position
  55. GRB 090929: Enhanced Swift-XRT position
  56. GRB 090929B: Swift detection of a burst
  57. GRB 090929A: Fermi GBM detection
  58. GRB090926A: Swift-XRT refined analysis
  59. GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
  60. Konus-Wind and Konus-RF observations of GRB 090926A
  61. GRB 090927: VLT redshift
  62. GRB 090926B: Fermi GBM detection
  63. GRB 090927: Zadko Telescope observations
  64. GRB 090927, Swift-BAT refined analysis of the possibly short burst
  65. Swift/UVOT observations of GRB 090927
  66. GRB 090926A: Skynet/PROMPT Continued Observations
  67. GRB 090927: Swift XRT refined analysis
  68. GRB 090926A: Suzaku WAM observation of the prompt emission
  69. GRB 090927: Enhanced Swift-XRT position
  70. GRB090926B: Swift/UVOT Upper Limits
  71. GRB090926A: Swift/UVOT observations
  72. GRB 090926B: VLT spectroscopy
  73. GRB 090927: Swift/UVOT detection of an optical afterglow
  74. GRB 090927: Swift detection of a short burst
  75. GRB 090926B: optical object in error circle
  76. GRB 090926B: MAXI GSC detection
  77. GRB 090926A: VLT/X-shooter redshift
  78. GRB 090926B: NOT optical observation
  79. GRB 090926B: Swift XRT refined analysis
  80. GRB 090926B: Swift-BAT refined analysis
  81. GRB 090926A: Swift/UVOT detection of an optical afterglow
  82. GRB 090926A: Skynet/PROMPT Discovery of the Optical Afterglow
  83. GRB090926A: UVOT-enhanced XRT position
  84. GRB 090926B: Swift detection of a burst
  85. GRB 090926: Fermi LAT detection
  86. GRB 090926: Fermi GBM detection
  87. GRB 090925: Fermi GBM detection
  88. GRB090904B : IRSF NIR upper limit
  89. GRB090922A: correction to Fermi location
  90. GRB 090922A: Fermi GBM detection
  91. Swift returns to normal operations
  92. GRB 090715B: Skynet/PROMPT Detections
  93. GRB 090726: Skynet/GORT Observations
  94. GRB 090916: Swift-XRT upper limit
  95. GRB 090807: Skynet/DSO Observations
  96. GRB 090915: GROND upper limits
  97. Swift-BAT temporarily off-line for a few days
  98. Short-Duration GRB 090916: Skynet/PROMPT Observations
  99. GRB 090915: SARA detection of afterglow candidate
  100. GRB 090912: optical observation

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