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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 130211A: GROND detection of the afterglow
  2. GRB 130211A: Swift detection of a burst
  3. GRB 130131A: MITSuME Akeno Optical upper limits
  4. GRB 130131B: MITSuME Akeno Optical upper limits
  5. GRB 130122A: PTF P48 optical upper limits
  6. GRB 130206A: GROND Observations
  7. GRB 130206A: Fermi LAT Observations
  8. GRB 130206A: Fermi GBM observation
  9. GRB 130206A: XRT and UVOT follow-up observations.
  10. GRB 130131B: optical upper limit in Mondy observatory
  11. GRB 130206A, Swift-BAT refined analysis
  12. GRB 130206A: Zadko observatory - Gingin optical observations
  13. Swift GRB 130206A - analysis of Swift/UVOT initial data.
  14. GRB 130206A: Swift-XRT observations
  15. GRB 130131A: optical observation in Mondy observatory
  16. GRB 130206A: Swift detection of a burst
  17. GRB 130131A: Swift/UVOT Upper Limits
  18. GRB 130131B: RATIR Upper Limits
  19. GRB 130131A: RATIR optical and infrared upper limits
  20. GRB 130131A: RAPTOR Limits During Gamma-Ray Emitting Interval
  21. GRB 130131B: Swift-XRT refined Analysis
  22. GRB 130131A - UKIRT confirmation of afterglow
  23. GRB 130131B: VLT/X-shooter acquisition camera limits
  24. GRB 130131B: GROND Upper limits
  25. GRB 130131A: CARMA 3mm Observations
  26. GRB 130131A: VLA 5.8 Ghz Detection
  27. GRB 130131B: IAC80 I-band observations
  28. GRB 130131B: Swift/UVOT Upper Limits
  29. GRB 130131A: Swift-XRT refined Analysis
  30. GRB 130131B: MITSuME Okayama optical upper limits
  31. GRB 130131A: MITSuME Okayama optical upper limits
  32. GRB 130131B: Enhanced Swift-XRT position
  33. GRB 130131B: Swift-BAT refined analysis
  34. GRB 130131A: Swift-BAT refined analysis
  35. GRB 130131B: TAROT Calern observatory optical observations
  36. GRB 130131B: Zadko observatory - Gingin optical observations
  37. GRB 130131A: Enhanced Swift-XRT position
  38. GRB 130131B: Swift detection of a burst
  39. GRB 130131A - Faulkes Telescope North Observations
  40. GRB 130131A - UKIRT afterglow candidate
  41. GRB 130131A: Swift detection of a burst
  42. Swift/BAT trigger 547142 is new source Swift J1753.7-2544
  43. GRB 130127A: Fermi GBM detection
  44. Swift Trigger 547142: MAXI/GSC upper limit
  45. GRB 130122A: RTT150 optical observations
  46. Swift Trigger 547142: a probable Galactic source
  47. GRB 130122A: CARMA 3mm Observations
  48. GRB 130122A: Swift/UVOT Detection
  49. GRB 130122A: optical observations
  50. GRB 130122A: RATIR Detection
  51. GRB 130122A: Swift-BAT refined analysis
  52. GRB 130122A: Swift-XRT refined Analysis
  53. GRB 130122A: Xinglong optical upper limit
  54. GRB 130122A: Enhanced Swift-XRT position
  55. GRB 130122A: MASTER-Net early marginal detection of the OT
  56. GRB 130122A: T100 observations
  57. GRB 130122A: Swift detection of a burst with an optical counterpart
  58. Short GRB 121226A: TNG observation of the host galaxy
  59. GRB 121225B: Suzaku WAM observation of the prompt emission
  60. GRB 130102B: MASTER synchronous observations
  61. GRB 130102A: Swift/UVOT Upper Limits
  62. Konus-Wind observation of GRB 130102B
  63. GRB 130102A: P60 Observations
  64. GRB 130102A: Swift-BAT refined analysis
  65. GRB 130102A: MASTER-Net optical observations
  66. GRB 130102A: Swift-XRT refined Analysis
  67. GRB 130102B: MAXI/GSC detection
  68. GRB 130102A: Enhanced Swift-XRT position
  69. GRB 130102A: IAC80 I-band observations
  70. GRB 130102A: Swift detection of a burst
  71. GRB 121226A: 5.8 GHz VLA observations
  72. Swift Trigger 544381 is a noise event
  73. GRB 121229A: Swift-XRT refined Analysis
  74. GRB 121229A, Swift-BAT refined analysis
  75. GRB 121229A: Swift/UVOT Upper Limits
  76. GRB 121229A: Enhanced Swift-XRT position
  77. GRB 121229A: VLT/X-shooter redshift
  78. Swift Trigger 544381 is unlikely to be a GRB
  79. GRB 121229A: MAXI/GSC detection
  80. GRB 121229A: GROND detection of the afterglow
  81. Skynet/PROMPT observations of GRB121229a
  82. GRB 121229A: Swift detection of a burst
  83. GRB 121226A: 10.4m GTC optical observations
  84. GRB 121226A: Swift/UVOT Upper Limits
  85. GRB 121226A: Swift-XRT refined Analysis
  86. GRB 121226A, Swift-BAT refined analysis
  87. GRB 121226A: NOT optical upper limit
  88. GRB 121226A: Optical Observations
  89. GRB 121226A: MITSuME Okayama Optical upper limits
  90. GRB 121226A: Zadko observatory - Gingin optical observations
  91. GRB 121226A: BOOTES-4/MET optical observations
  92. GRB 121226A: Swift detection of a burst
  93. Konus-Wind observation of GRB 121225B
  94. IPN Triangulation of GRB 121225B
  95. GRB 121225B: Fermi GBM observation
  96. GRB 121225B: Fermi LAT Detection
  97. GRB 121225A: MAXI/GSC detection
  98. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  99. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  100. GRB 121217A: ATCA 44GHz upper limit

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