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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').
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"

12336 results found.

  1. GRB 100206A: optical observations from Southern Spain
  2. GRB 100205A: GROND upper limits
  3. GRB 100206A: Swift detection of a short hard burst
  4. GRB 100205A: Swift UVOT upper limits
  5. GRB 100203A: Swift XRT and UVOT refined analyses
  6. GRB 100205A: Swift detection of a burst
  7. Short X-ray Transient detected by MAXI/GSC
  8. Swift/UVOT refined analysis of GRB100117A
  9. GRB 100117A: Swift-XRT refined analysis
  10. GRB 100117A: Gemini-North upper limit
  11. GRB 100117A: Swift detection of a short hard burst
  12. GRB 100115A: Swift/UVOT Upper Limits
  13. GRB 100111A: PAIRITEL NIR Upper Limits
  14. GRB 100111A: Swift UVOT Refined Analysis
  15. GRB 100103A: GROND Upper Limits
  16. GRB 100103A: Swift/UVOT Upper Limits
  17. Swift Trigger 381591 is probably not a burst
  18. GRB 091231: GROND NIR observations
  19. Swift Trigger 381591: Uncatalogued UVOT Source
  20. GRB 091230: Swift/UVOT Observations
  21. Trigger 381591: Swift detection of a possible burst
  22. Swift Trigger 381434 is not a GRB
  23. Trigger 381434: Swift detection of a possible burst
  24. GRB 091221 : IRSF NIR upper limit
  25. GRB 091221: Swift/UVOT refined analysis
  26. GRB 091221: UVOT Confirmation of an Optical Afterglow
  27. GRB 091221: Swift detection of a burst
  28. Swift trigger 379449 (possible GRB) is not a burst
  29. GRB 091215: Faulkes Telescope North observations
  30. Trigger 379449: Swift detection of a possible burst
  31. GRB091208A: Swift/UVOT refined analysis
  32. GRB 091208A: Swift-XRT observations
  33. GRB 091208A, RIMOTS optical upper limits
  34. GRB 091208B, RIMOTS optical upper limits
  35. Short X-ray Transient, RIMOTS optical upper limits
  36. GRB 091202: Swift/UVOT Upper Limits
  37. Short X-ray Transient Detection by MAXI/GSC
  38. GRB 091130A: Xinglong TNT upper limit
  39. GRB 091130B: Swift/UVOT Upper Limits
  40. Swift trigger 377436 (possible GRB 091130A) is not a burst
  41. GRB 091130B: Swift detection of a burst
  42. GRB 091127: Radio observations
  43. GRB 091117A: Swift/UVOT followup observations
  44. GRB 091117: Swift-XRT observations
  45. GRB 091109A: GROND and VLT observations
  46. GRB 091109B: Swift/UVOT Upper Limits
  47. GRB 091109B: Swift detection of a short burst
  48. GRB 091109: Swift/UVOT observations
  49. GRB 091104: Swift/UVOT Upper Limits
  50. GRB091026 : IRSF NIR upper limit
  51. GRB091102 : MOA optical upper limit
  52. GRB 091104: Swift detection of a burst
  53. Fermi LAT Upper Limits on GRB 091010
  54. GRB 091102 : Faulkes Telescope South Upper Limits
  55. GRB 091102: Swift/UVOT Upper Limits
  56. GRB 091102: GROND Upper Limits
  57. GRB 091102: Swift/UVOT Finding Chart Observation
  58. GRB 091024: Fermi LAT upper limits
  59. GRB091029: Swift/UVOT observations
  60. GRB 091024: Keck/LRIS Spectroscopy
  61. GRB 091026: GROND Upper Limits
  62. GRB 091026: Swift/UVOT Upper Limits
  63. GRB 091026: Swift detection of a Gamma Ray Burst
  64. GRB 091020 : Xinglong TNT upper limit
  65. GRB091024 Swift/UVOT Upper Limits
  66. GRB 091024: TLS Upper Limit
  67. GRB 091024: GRAS004 optical observations
  68. GRB091020 Swift/UVOT observations
  69. GRB 091020: NOT spectroscopic redshift
  70. Konus-RF observation of GRB 091018
  71. GRB 090726 R band observations
  72. GRB 091010: optical afterglow candidate rejection
  73. GRB 091010: AGILE-MCAL measurement and GRID upper limit
  74. GRB 091010 optical upper limits
  75. GRB 091010: Swift/UVOT Upper Limits
  76. GRB 091003: WHT ACAM observations
  77. Konus-Wind observation of GRB 091003A
  78. GRB 091003: Swift/UVOT Detection of an Optical Afterglow
  79. GRB 090929A: Swift/UVOT Observations
  80. GRB 090929A: Swift-XRT non-detection
  81. GRB 090929B: Gemini-N upper limits
  82. GRB 090929B: Swift/UVOT Observations
  83. Konus-RF observation of GRB 090929A
  84. GRB 090929B: Swift detection of a burst
  85. GRB090926B: Swift/UVOT Upper Limits
  86. GRB 090926B: Swift detection of a burst
  87. GRB090904B : IRSF NIR upper limit
  88. GRB 090916: Swift-XRT upper limit
  89. GRB 090915: GROND upper limits
  90. GRB 090915: Swift-XRT detection of a fading X-ray counterpart
  91. GRB 090827: Confirmation of the X-ray afterglow
  92. GRB 090912: Swift/UVOT Upper Limits
  93. GRB 090912 optical upper limit
  94. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  95. GRB 090904A: Swift/UVOT Refined Analysis
  96. GRB 090904B: Swift/UVOT Refined Analysis
  97. GRB 090904B: Swift detection of a burst
  98. GRB 090831C: GROND upper limits
  99. Swift Trigger 361477, called GRB090831B, is probably not real.
  100. GRB090831C: Swift/UVOT upper limits

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