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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. SGR 1833-0832 is pulsed at 7.56 seconds
  2. SGR 1833-0832 is pulsed at 7.56 seconds
  3. Possible pulsation period in SGR 1833-0832
  4. Discovery of the Spin Period of SGR 1833-0832
  5. GRB 100316D: ATCA radio observations
  6. GRB 100319A: correction to GCN 10527
  7. Probable SGR 1833-0832: Swift-XRT refined analysis
  8. Probable SGR 1833-0832: Enhanced Swift-XRT position
  9. Swift-XRT refined position of the probable new SGR 1833-0832
  10. Swift-BAT refined analysis of the probable new SGR 1833-0832
  11. GRB 100219A: MASTER-Net optical alert observations
  12. GRB 100319A: Swift detection of a burst; possible SGR
  13. GRB 100316D: Possible Supernova
  14. GRB 100316D: Pre-burst emission measured by BAT
  15. GRB 100316D: Further Gemini observations
  16. GRB 100219A: optical upper limit
  17. GRB 100316A: optical observations in CrAO
  18. GRB 100316D: Swift/UVOT Observations
  19. GRB 100316D: Swift XRT enhanced position and further refined analysis
  20. GRB 100316B: Swift-XRT refined analysis
  21. Tentative redshift of GRB100316D from X-ray data
  22. GRB 100316C: GROND Detection of a Optical/NIR Afterglow Candidate
  23. Trigger 416226 is probably not a GRB
  24. GRB 100316D: GROND Detection of the Optical/NIR Afterglow Candidate
  25. GRB 100316D: Gemini/GMOS and VLT/X-shooter observations
  26. GRB 100316D: VLT/X-shooter observations
  27. GRB 100316D: Swift-BAT refined analysis
  28. GRB100316C: Swift/UVOT Upper Limits
  29. GRB 100316C: Swift-BAT refined analysis
  30. GRB 100316B: Swift/UVOT observations
  31. GRB 100316C: Swift-XRT team refined analysis
  32. GRB 100316C: Enhanced Swift-XRT position
  33. GRB 100316D: Swift XRT refined analysis
  34. GRB 100316A: TAROT Calern observatory optical observations
  35. GRB 100316A: Swift-XRT refined analysis
  36. GRB 100316B: Enhanced Swift-XRT position
  37. GRB 100316A: Swift-BAT refined analysis
  38. GRB 100316B: Swift-BAT refined analysis
  39. GRB100316A: Swift/UVOT Upper Limits
  40. Trigger 416140 is almost certainly not a GRB
  41. GRB 100316C: BOOTES-3 observations
  42. GRB 100316D: Swift detection of a burst
  43. GRB 100316B: VLT/X-shooter redshift
  44. GRB 100316B: Skynet/PROMPT Observations of Fading
  45. GRB 100316B: GROND Detection of the Optical/NIR Afterglow Candidate
  46. XRF 100315A: MAXI/GSC detection of a short X-ray transient
  47. GRB 100316C: Swift detection of a burst
  48. GRB 100316A: Enhanced Swift-XRT position
  49. GRB 100316B: Swift detection of a burst with optical counterpart
  50. GRB 100316 optical candidate from 1.23m CAHA telescope
  51. GRB 100316 optical candidate from 1.23m CAHA telescope
  52. GRB 100316A: Swift/UVOT Observations
  53. GRB 100316A: Swift-XRT detection
  54. GRB 100316A: Swift detection of a burst
  55. IBAS Alert 5992 is not a GRB, but XTE J1855-026
  56. GRB100305A: Optical upper limits at IAO
  57. GRB 100305A: Super-LOTIS early observations
  58. GRB100302A : LOAO observations and Lulin afterglow analysis
  59. GRB 100305A, Swift-BAT refined analysis
  60. GRB 100305A: Gemini z'-band observation
  61. GRB 100305A: Swift/UVOT Upper Limits
  62. GRB 100305A: Swift-XRT refined analysis
  63. GRB 100305A Optical Observations
  64. GRB 100305A: Enhanced Swift-XRT position
  65. GRB 100305A: Gemini-N OT candidate
  66. GRB 100305A: PAIRITEL NIR Upper Limits
  67. GRB 100305A: P60 Observations
  68. GRB 100305A: Swift detection of a burst
  69. GRB 100302A: Ondrejov 65cm limit
  70. GRB 100302A: Swift/UVOT Upper Limits
  71. GRB 100302A: Swift-XRT refined analysis
  72. GRB 100302A: Gemini-North redshift
  73. GRB 100302A: Gemini-N OT confirmation
  74. GRB 100302A: Optical observations at Crni Vrh
  75. GRB 100302A: MASTER-Net optical alert observations
  76. GRB 100302A, Swift-BAT refined analysis
  77. GRB 1000302A : A possible afterglow candidate
  78. GRB 100302A: Enhanced Swift-XRT position
  79. GRB 100302A: Skynet/DAO Observations
  80. GRB 100302A: Swift detection of a burst
  81. GRB 100224B: Fermi GBM detection
  82. GRB 100206A: optical observations in CrAO
  83. GRB 100206A: optical observations in Terskol
  84. GRB 100213B: Mondy optical observations
  85. GRB 100219A: optical observations
  86. GRB 100219A: GAO 150cm telescope Optical Observation
  87. GRB 100224A SHB found in ground analysis of BAT data
  88. GRB 100225A: Fermi LAT detection
  89. GRB 100225A: Fermi GBM detection
  90. GRB 100223A: Fermi GBM detection
  91. Swift Triggers 413744 and 413745 are not GRBs
  92. GRB
  93. GRB 100219A: X-shooter refined analysis
  94. GRB 100219A: XRT refined analysis
  95. GRB 100219A - Gemini South Spectroscopy
  96. GRB 100216A: Swift/UVOT Observations
  97. GRB 100219A: VLT/X-shooter redshift
  98. GRB100219A Akeno and Okayama MITSuME Optical Observation
  99. GRB 100219A: GROND observations
  100. GRB 100219A: NOT OA observations

Advanced

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