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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"

38134 results found.

  1. GRB 100213A: Swift-BAT lag analysis indicates probably SHB
  2. GRB 100213B: GRT Optical Observation
  3. GRB 100213A: GRT Optical Observation
  4. GRB 100213A: Swift-BAT refined analysis
  5. GRB 100213B: Enhanced Swift-XRT position
  6. GRB 100213B: Gemini-N Observations
  7. GRB 100213B: Swift/UVOT Upper Limits
  8. GRB 100213A: Swift/UVOT Upper Limits
  9. GRB 100213B: PAIRITEL NIR Upper Limits
  10. GRB 100213A: Enhanced Swift-XRT position
  11. GRB 100213B: Swift-BAT refined analysis
  12. GRB 100213B: Swift XRT refined analysis
  13. GRB 100213A: SARA observations
  14. GRB 100213A: Swift XRT refined analysis
  15. GRB 100213B: NOT optical observations
  16. GRB 100213B: Swift detection of a burst
  17. GRB 100213A: Swift detection of a burst
  18. GRB 100206A: Second epoch Gemini-north observations and afterglow limits
  19. Swift/UVOT observations of GRB120212A
  20. GRB 100212A: LOAO R-band Detection/V-band Observation
  21. GRB 100212A: Fermi GBM detection
  22. GRB 100212A: Swift XRT refined analysis
  23. GRB 100212A: Swift-BAT refined analysis
  24. GRB 100212A: Enhanced Swift-XRT position
  25. GRB 100212A: candidate optical afterglow
  26. GRB 100212A: Swift detection of a burst
  27. GRB 091127: Detection of a Supernova
  28. GRB 100205A: Keck limits on an underlying host galaxy
  29. GRB 100205A: BOAO/LOAO zYJK observation
  30. GRB 100205B: Fermi GBM detection
  31. GRB 100206A: GROND upper limits
  32. GRB 100206A: Gemini-North observations
  33. GRB 100206A: Swift/UVOT Upper Limits
  34. GRB 100131A: MASTER-Net optical alert observations
  35. GRB 100206A: YNAO-GMG observations
  36. GRB 100206A: MASTER-Net optical alert observations
  37. GRB 100206A: PAIRITEL Photometry of Host Candidate
  38. GRB 100206A - Keck/LRIS Spectroscopy
  39. GRB100206: MITSuME optical upper limits
  40. GRB 100206A: NOT NIR observations
  41. GRB 100206A: WHT candidate afterglow
  42. GRB 100206A, RIMOTS optical upper limits
  43. GRB 100206A: optical observations from Southern Spain
  44. GRB 100205A: GROND upper limits
  45. GRB 100206A: Swift-XRT refined analysis
  46. GRB 100206A: Fermi GBM observation
  47. GRB 100206A: Optical limit
  48. GRB 100206A: Swift-BAT refined analysis
  49. GRB 100206A: Enhanced Swift-XRT position
  50. GRB 100206A: Pre-explosion imaging and host candidate
  51. GRB 100206A: Swift detection of a short hard burst
  52. GRB 100205A: Gemini-N + NIRI photometry
  53. GRB 100130B: Fermi GBM detection
  54. GRB 100113A: Fermi GBM detection
  55. GRB 100205A: Swift-BAT refined analysis
  56. GRB 100205A: Swift UVOT upper limits
  57. GRB 100205A: Swift XRT refined analysis
  58. GRB 100203A: Swift XRT and UVOT refined analyses
  59. GRB 100205A: Enhanced Swift-XRT position
  60. GRB 100205A Gemini-North IR afterglow candidate
  61. GRB 100205A: Gemini-South Observations
  62. GRB 100205A: Super-LOTIS early observations
  63. GRB 100131A: Suzaku WAM observation of the prompt emission
  64. GRB 100205A: NOT optical observations
  65. GRB 100205A: Swift detection of a burst
  66. GRB 100203A Detected in Ground Analysis of BAT Data
  67. Short X-ray Transient detected by MAXI/GSC
  68. GRB 100131A: Fermi GBM detection
  69. GRB 100119A: Suzaku WAM observation of the prompt emission
  70. Konus-Wind observation of GRB 100119A
  71. GRB 100122A: Fermi GBM detection
  72. GRB 100122A: MASTER-Net optical observations
  73. GRB 100116A: Suzaku WAM observation of the prompt emission
  74. GRB 100115A: Swift-XRT refined analysis
  75. GRB 100119A: Swift-BAT refined analysis
  76. GRB091109A: VLT/FORS2 spectroscopic redshift
  77. GRB 100117A: candidate optical afterglow
  78. GRB 100119A: Swift detection of a burst
  79. Konus-Wind observation of GRB 100116A
  80. GRB 100117A: Gemini North spectroscopy
  81. GRB 100117A: Fermi GBM detection
  82. Swift/UVOT refined analysis of GRB100117A
  83. GRB 100117A: Optical object inside the revised XRT error circle
  84. GRB 100117A: Swift-XRT refined analysis
  85. GRB 100117A: Gemini-North upper limit
  86. GRB 100117A: Magellan IMACS imaging
  87. GRB 100117A: Gemini South Imaging and CFHT Pre-Explosion Images
  88. GRB 100117A: Swift-BAT refined analysis
  89. GRB 100117A: Swift detection of a short hard burst
  90. GRB 100115A: Gemini-N photometry
  91. GRB 100115A: Enhanced Swift-XRT position
  92. GRB 100116A: Fermi LAT detection
  93. GRB 100115A: SARA Astrometry
  94. GRB 100116A: Fermi GBM detection
  95. NOT observation of GRB100115A localization
  96. GRB 100115A: SARA Afterglow Candidate
  97. GRB 100115A: Swift/UVOT Upper Limits
  98. GRB 100115A: Swift-XRT candidate afterglow
  99. GRB 100115A detected in ground analysis of Swift-BAT data
  100. GRB 100111A: PAIRITEL NIR Upper Limits

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Download all Circulars as a .tar.gz archive (updated once a day):
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