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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"
  1. GRB 100213B: Enhanced Swift-XRT position
  2. GRB 100213B: Gemini-N Observations
  3. GRB 100213B: Swift/UVOT Upper Limits
  4. GRB 100213A: Swift/UVOT Upper Limits
  5. GRB 100213B: PAIRITEL NIR Upper Limits
  6. GRB 100213A: Enhanced Swift-XRT position
  7. GRB 100213B: Swift-BAT refined analysis
  8. GRB 100213B: Swift XRT refined analysis
  9. GRB 100213A: SARA observations
  10. GRB 100213A: Swift XRT refined analysis
  11. GRB 100213B: NOT optical observations
  12. GRB 100213B: Swift detection of a burst
  13. GRB 100213A: Swift detection of a burst
  14. GRB 100206A: Second epoch Gemini-north observations and afterglow limits
  15. Swift/UVOT observations of GRB100212A - correction of the name of the burst
  16. Swift/UVOT observations of GRB120212A
  17. GRB 100212A: LOAO R-band Detection/V-band Observation
  18. GRB 100212A: Fermi GBM detection
  19. GRB 100212A: Swift XRT refined analysis
  20. GRB 100212A: Swift-BAT refined analysis
  21. GRB 100212A: Enhanced Swift-XRT position
  22. GRB 100212A: candidate optical afterglow
  23. GRB 100212A: Swift detection of a burst
  24. GRB 091127: Detection of a Supernova
  25. GRB 100205A: Keck limits on an underlying host galaxy
  26. GRB 100205A: BOAO/LOAO zYJK observation
  27. GRB 100205B: Fermi GBM detection
  28. GRB 100206A: GROND upper limits
  29. GRB 100206A: Gemini-North observations
  30. GRB 100206A: Swift/UVOT Upper Limits
  31. GRB 100131A: MASTER-Net optical alert observations
  32. GRB 100206A: YNAO-GMG observations
  33. GRB 100206A: MASTER-Net optical alert observations
  34. GRB 100206A: PAIRITEL Photometry of Host Candidate
  35. GRB 100206A - Keck/LRIS Spectroscopy
  36. GRB100206: MITSuME optical upper limits
  37. GRB 100206A: NOT NIR observations
  38. GRB 100206A: WHT candidate afterglow
  39. GRB 100206A, RIMOTS optical upper limits
  40. GRB 100206A: optical observations from Southern Spain
  41. GRB 100205A: GROND upper limits
  42. GRB 100206A: Swift-XRT refined analysis
  43. GRB 100206A: Fermi GBM observation
  44. GRB 100206A: Optical limit
  45. GRB 100206A: Swift-BAT refined analysis
  46. GRB 100206A: Enhanced Swift-XRT position
  47. GRB 100206A: Pre-explosion imaging and host candidate
  48. GRB 100206A: Swift detection of a short hard burst
  49. GRB100205A: CFHT z'-band observation
  50. GRB 100205A: Gemini-N + NIRI photometry
  51. GRB 100130B: Fermi GBM detection
  52. GRB 100113A: Fermi GBM detection
  53. GRB 100205A: Swift-BAT refined analysis
  54. GRB 100205A: Swift UVOT upper limits
  55. GRB 100205A: Swift XRT refined analysis
  56. GRB 100203A: Swift XRT and UVOT refined analyses
  57. GRB 100205A: Enhanced Swift-XRT position
  58. GRB 100205A Gemini-North IR afterglow candidate
  59. GRB 100205A: Gemini-South Observations
  60. GRB 100205A: Super-LOTIS early observations
  61. GRB 100131A: Suzaku WAM observation of the prompt emission
  62. GRB 100205A: NOT optical observations
  63. GRB 100205A: Swift detection of a burst
  64. GRB 100203A Detected in Ground Analysis of BAT Data
  65. Short X-ray Transient detected by MAXI/GSC
  66. GRB 100131A: Fermi GBM detection
  67. GRB 100119A: Suzaku WAM observation of the prompt emission
  68. Konus-Wind observation of GRB 100119A
  69. GRB 100122A: Fermi GBM detection
  70. GRB 100122A: MASTER-Net optical observations
  71. GRB 100116A: Suzaku WAM observation of the prompt emission
  72. GRB 100115A: Swift-XRT refined analysis
  73. GRB 100119A: Swift-BAT refined analysis
  74. GRB091109A: VLT/FORS2 spectroscopic redshift
  75. GRB 100117A: candidate optical afterglow
  76. GRB 100119A: Swift detection of a burst
  77. Konus-Wind observation of GRB 100116A
  78. GRB 100117A: Gemini North spectroscopy
  79. GRB 100117A: Fermi GBM detection
  80. Swift/UVOT refined analysis of GRB100117A
  81. GRB 100117A: Optical object inside the revised XRT error circle
  82. GRB 100117A: Swift-XRT refined analysis
  83. GRB 100117A: Gemini-North upper limit
  84. GRB 100117A: Magellan IMACS imaging
  85. GRB 100117A: Gemini South Imaging and CFHT Pre-Explosion Images
  86. GRB 100117A: Swift-BAT refined analysis
  87. GRB100117A: Possible afterglow from NOT observation
  88. GRB 100117A: Swift detection of a short hard burst
  89. GRB 100115A: Gemini-N photometry
  90. GRB 100115A: Enhanced Swift-XRT position
  91. GRB 100116A: Fermi LAT detection
  92. GRB 100115A: SARA Astrometry
  93. GRB100115A: Revision of NOT observation
  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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