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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"

38114 results found.

  1. GRB 091230: a long GRB detected by INTEGRAL
  2. Swift Trigger 381434 is not a GRB
  3. Trigger 381434: Swift detection of a possible burst
  4. GRB 091221 : IRSF NIR upper limit
  5. GRB 091221: Skynet/PROMPT Detections
  6. GRB 091221: Fermi GBM Observation
  7. GRB 091117: Swift-XRT late time observations
  8. GRB 091221 Swift-BAT refined analysis
  9. GRB 091221: Swift/UVOT refined analysis
  10. GRB 091221: Swift-XRT refined analysis
  11. GRB 091221: Enhanced Swift-XRT position
  12. GRB 091221, GROND observations
  13. GRB 091221: UVOT Confirmation of an Optical Afterglow
  14. GRB 091221: ROTSE-III Detection of Optical Counterpart
  15. GRB 091221: Swift detection of a burst
  16. Swift trigger 379449 (possible GRB) is not a burst
  17. GRB 091215: Faulkes Telescope North observations
  18. Trigger 379449: Swift detection of a possible burst
  19. GRB 091208B: Xinglong TNT optical observation
  20. GRB 091208A: Suzaku WAM observation of the prompt emission
  21. GRB 091208A: GAO 150cm telescope Optical Observation
  22. Konus-Wind observation of GRB 091208A
  23. GRB 091208B: GAO 150cm telescope Optical Observation
  24. GRB 091208B: optical observations
  25. GRB 091208B: Keck HIRES redshift confirmation
  26. GRB 091208B: GROND observations
  27. GRB 091208A: Swift-XRT observations
  28. GRB 091208B: Swift-XRT refined analysis
  29. GRB091208B: Swift/UVOT refined analysis
  30. GRB 091208B: Fermi GBM observation
  31. GRB 091208B, Swift-BAT refined analysis
  32. GRB 091208A Swift-BAT refined analysis
  33. GRB 091208B: Gemini-North redshift
  34. GRB 091208B: Faulkes Telescope North and South Optical Afterglow
  35. GRB 091208A, RIMOTS optical upper limits
  36. GRB 091208B: MITSuME Akeno Optical Observation
  37. GRB 091208B: Enhanced Swift-XRT position
  38. GRB 091208B: MITSuME Okayama Optical Observation
  39. GRB 091208B, RIMOTS optical upper limits
  40. GRB 091208B: Swift detection of a burst with an optical afterglow
  41. GRB 091208B: BOOTES-3 optical afterglow
  42. GRB 091208: ROTSE-III Optical Limits
  43. GRB 091208: Swift detection of a burst
  44. A small revision to the GRB-naming convention
  45. GRB 091123: Suzaku WAM observation of the prompt emission
  46. GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
  47. GRB 091127: GAO 150cm telescope Optical Observation
  48. GRB 091202: GTC & CAHA optical/nIR afterglow candidate
  49. GRB 091109A: GROND confirmation of redshift z = 3.5
  50. GRB091127: Continuing Swift/UVOT Observations
  51. GRB 091127, SMARTS optical/IR afterglow observations
  52. GRB091202: Swift-XRT refined analysis
  53. GRB 091202: Swift/UVOT Upper Limits
  54. GRB 091202: Liverpool Telescope observations
  55. GRB 091202: Optical and NIR observations
  56. GRB 091202 - UVOT-enhanced XRT position
  57. GRB 091127: Zadko Telescope Observations
  58. GRB 091126A: Suzaku WAM observation of the prompt emission
  59. GRB 091202: TAROT Calern observatory optical observations
  60. GRB 091202: Liverpool Telescope Observations
  61. GRB 091202: a long GRB detected by INTEGRAL
  62. GRB 091127: redshift confirmation with X-shooter
  63. GRB 091117: Chandra Observations
  64. GRB 091020: MASTER-Net optical polarization observations
  65. GRB 091127: Skynet/PROMPT Continued Observations of Fading
  66. Short X-ray Transient Detection by MAXI/GSC
  67. Konus-Wind observation of very long GRB 091123
  68. GRB 091130A: Xinglong TNT upper limit
  69. GRB 091123: Fermi GBM detection of a very long burst
  70. GRB 091126B: Fermi GBM detection
  71. GRB 091127: Suzaku WAM observation of the prompt emission
  72. GRB 091126: Fermi GBM detection
  73. GRB 091130B: Swift-XRT team refined analysis
  74. GRB 091130B: Swift-BAT refined analysis
  75. GRB 091130B: Swift/UVOT Upper Limits
  76. GRB 091127: Skynet/PROMPT Observations of Fading
  77. GRB 091130B: Enhanced Swift-XRT position
  78. Swift trigger 377436 (possible GRB 091130A) is not a burst
  79. GRB 091130B: MASTER observations
  80. GRB 091130B: SDSS galaxy at XRT location
  81. GRB 091130B: Swift detection of a burst
  82. GRB 091130: MASTER observations
  83. GRB 091130: Swift detection of a possible burst
  84. GRB 091127: Radio observations
  85. GRB 091128: Fermi GBM detection
  86. Konus-Wind observation of GRB 091127
  87. GRB 091127: TAROT La Silla observatory optical observations
  88. GRB 091127: optical observations
  89. GRB 091127: LABOCA/APEX submm observations
  90. GRB 091127: Further NOT optical observations
  91. GRB 091127: Fermi GBM detection
  92. GRB 091127: MASTER early optical transient polarimetry
  93. GRB 091127: Gemini-N redshift
  94. GRB 091127: Swift-XRT afterglow detection and analysis
  95. GRB 091127: TAROT La Silla observatory optical decay
  96. GRB 091127: Swift/UVOT observations
  97. GRB 091127: CAHA 1.23m I-band observations
  98. GRB 091127: Swift-BAT refined analysis
  99. GRB 091127: NOT observations
  100. GRB 091127 : GROND observations

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