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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"

20542 results found.

  1. GRB 061222B: Swift detection of a burst
  2. GRB 061222A: Prompt ROTSE-III Optical Limits
  3. GRB 061222: Swift detection of a burst
  4. GRB 061218: TAROT La Silla observatory optical observations
  5. GRB 061217: TAROT Calern observatory optical observations
  6. GRB 061218: TORTOREM optical upper limits
  7. GRB 061218, Swift-BAT refined analysis
  8. GRB061217: VLT NIR observations
  9. GRB 061218, SMARTS optical/IR observations
  10. GRB 061218: REM prompt observations
  11. Swift triggers (#251863) on a possible burst
  12. GRB061217: Swift/UVOT refined analysis.
  13. GRB 061217: optical observations at Calar Alto
  14. GRB061217 - Swift/XRT refined analysis
  15. GRB 061217: Magellan Observations
  16. GRB 061217: REM prompt observations
  17. GRB 061217: ROTSE-III Optical Limits
  18. GRB061210: Swift/UVOT observations
  19. GRB 061210: Swift XRT analysis - Possible counterparts
  20. GRB 061214(?): Swift detection of a possible burst
  21. GRB 061210: Gemini/GMOS Observations
  22. GRB 061126: Radio Observations
  23. GRB061210: Radio Observations
  24. GRB 061210: Swift-BAT detection of a short burst
  25. Optical Afterglow observations of GRB 061126
  26. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  27. GRB 061202: TORTOREM optical upper limits
  28. GRB 061201: VLT optical decay
  29. GRB 061201: SOAR Confirmation of Candidate Afterglow
  30. GRB061202: FRAM early follow-up limit
  31. GRB061202 optical limit by "Pi of the Sky"
  32. GRB061202: optical/NIR observations with REM
  33. GRB061202: Swift/UVOT Upper Limits
  34. GRB 061202: Swift detection of a burst
  35. GRB 061201: Swift XRT Team refined analysis
  36. GRB 061201: VLT optical observations
  37. INT+WFC observations of GRB 061126
  38. GRB 061126: Possible Jet Break
  39. GRB061126: Optical afterglow observations from MIRO
  40. GRB061126: Optical afterglow observations from MIRO
  41. GRB 061126 : SDSS Pre-Burst Observations
  42. GRB 061126: Swift/UVOT Observations
  43. GRB 061126: Early Detection of the IR Afterglow
  44. GRB 061122: Candidate Optical Afterglow
  45. GRB061122: Swift/UVOT Optical Observations
  46. GRB061121: P60 Observations
  47. Radio detection of GRB 061121
  48. GRB061122: Swift-XRT position
  49. Swift-BAT trigger 239987 is not a GRB
  50. GRB 061121: Swift/UVOT Observations
  51. GRB061121, optical observation
  52. GRB 061121: Optical observation at the KANATA 1.5m telescope
  53. GRB 061121: Faulkes Telescope North Optical Observation
  54. GRB 061121: Swift detection of a bright burst with an optical counterpart
  55. GRB 060605: NIR Observations
  56. GRB 050915B: optical afterglow
  57. Swift/UVOT Upper Limits for GRB061110b
  58. Swift/UVOT Upper Limits for GRB061110a
  59. GRB 061110B: Swift XRT refined analysis
  60. GRB061110B: Optical observations at Crni Vrh
  61. GRB 061110B: TAROT Calern observatory optical observations
  62. GRB 061110B: Swift detection of a burst
  63. GRB 061110: Candidate confirmed
  64. GRB 061110: ROTSE-III Optical Limits
  65. GRB 061110: Swift detection of a burst
  66. GRB061110A - Optical Non-detection
  67. GRB 061109: TAROT Calern observatory optical observations
  68. GRB 061027: TAROT La Silla observatory optical observations
  69. GRB 061028: Swift/XRT Astrometry Correction
  70. GRB 061102: Swift/UVOT Magnitude Upper Limits
  71. GRB 061102, XRT refined analysis
  72. GRB061102B: Super-LOTIS observations
  73. GRB 061028: Optical R passband observations
  74. GRB 061102B: Swift detection of a possible burst
  75. GRB 061102: Swift detection of a burst
  76. GRB 061028: VLA Observation
  77. GRB 061004: Swift/XRT Astrometry Correction
  78. GRB 060801: Swift/XRT Astrometry Correction
  79. GRB 061028: Futher P200 Observations
  80. GRB 061028: P200 Observations
  81. GRB 061028: SARA upper limit
  82. GRB 061028: z band imaging
  83. GRB061028: XRT refined analysis
  84. GRB 061028: Swift/UVOT Observations
  85. GRB 061028: TAROT Calern observatory optical observations
  86. GRB 061028: Swift detection of a burst
  87. GRB 061027, Swift refined analysis of a possible burst
  88. GRB 061027: Swift detection of a possible burst
  89. GRB061025: Swift XRT refined analysis
  90. GRB061025: Swift/UVOT observations
  91. GRB 061025: REM observations
  92. GRB 061025: ROTSE-III Optical Limits
  93. Swift XRT boresight update
  94. GRB 061021: Swift/UVOT Observation
  95. GRB 061021: Swift detection of a burst
  96. GRB 061019: Super-LOTIS upper limit
  97. GRB060904b: optical observations
  98. GRB 061019: SARA upper limit
  99. GRB 061019: Swift/UVOT upper limit
  100. GRB061019: Swift XRT refined analysis

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