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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

21263 results found.

  1. GRB061217: Swift/UVOT refined analysis.
  2. GRB 061217: Magellan Observations
  3. GRB 061217: REM prompt observations
  4. GRB 061217: ROTSE-III Optical Limits
  5. GRB061210: Swift/UVOT observations
  6. GRB 061210: Swift XRT analysis - Possible counterparts
  7. GRB 061214(?): ROTSE-III Optical Limits
  8. GRB 061210: Suzaku WAM observation of the prompt emission
  9. GRB 061210: Gemini/GMOS Observations
  10. GRB 061126: Radio Observations
  11. GRB061210: Radio Observations
  12. GRB 061202: Suzaku WAM observation of the prompt emission
  13. GRB 061210, Swift-BAT refined analysis of the SHB
  14. Optical Afterglow observations of GRB 061126
  15. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  16. GRB 061202: TORTOREM optical upper limits
  17. GRB 061201: VLT optical decay
  18. GRB 061201: SOAR Confirmation of Candidate Afterglow
  19. GRB061202: FRAM early follow-up limit
  20. GRB061202 optical limit by "Pi of the Sky"
  21. Konus-Wind observation of GRB 061201
  22. GRB061202: optical/NIR observations with REM
  23. GRB061202: Swift/UVOT Upper Limits
  24. GRB 061202, Swift-BAT refined analysis
  25. GRB 061202: Swift detection of a burst
  26. GRB 061201: VLT optical observations
  27. INT+WFC observations of GRB 061126
  28. GRB 061126: Early Super-LOTIS Observations
  29. RHESSI Spectrum of GRB061126
  30. GRB061126: Optical afterglow observations from MIRO
  31. GRB061126: Optical afterglow observations from MIRO
  32. GRB 061126 : SDSS Pre-Burst Observations
  33. GRB 061126: Swift/UVOT Observations
  34. GRB 061126: Early Detection of the IR Afterglow
  35. GRB 061126: Swift detection of a burst
  36. GRB 061122: Candidate Optical Afterglow
  37. GRB061122: Swift/UVOT Optical Observations
  38. GRB 061121: ART detection in Ic
  39. GRB061121: P60 Observations
  40. Radio detection of GRB 061121
  41. GRB061122: Swift-XRT position
  42. Konus-Wind observation of GRB 061122
  43. RHESSI Spectrum of GRB061121
  44. Konus-Wind and Konus-A observations of GRB 061121
  45. Swift-BAT trigger 239987 is not a GRB
  46. GRB 061121: Swift/UVOT Observations
  47. GRB 061121, Swift-BAT refined analysis
  48. GRB061121, optical observation
  49. GRB 061121: Optical observation at the KANATA 1.5m telescope
  50. GRB 061121: Swift detection of a bright burst with an optical counterpart
  51. GRB 060605: NIR Observations
  52. GRB 050915B: optical afterglow
  53. Swift/UVOT Upper Limits for GRB061110b
  54. Swift/UVOT Upper Limits for GRB061110a
  55. GRB 061110B, Swift-BAT refined analysis
  56. GRB061110B: Optical observations at Crni Vrh
  57. GRB 061110A, Swift-BAT refined analysis
  58. GRB 061110B: TAROT Calern observatory optical observations
  59. GRB 061110B: Swift detection of a burst
  60. GRB 061110: Candidate confirmed
  61. GRB 061110: ROTSE-III Optical Limits
  62. GRB 061110: Swift detection of a burst
  63. GRB061110A - Optical Non-detection
  64. GRB 061109: TAROT Calern observatory optical observations
  65. GRB 061027: TAROT La Silla observatory optical observations
  66. GRB 061028: Swift/XRT Astrometry Correction
  67. GRB 061102: Swift/UVOT Magnitude Upper Limits
  68. GRB061102B: Super-LOTIS observations
  69. GRB 061028: Optical R passband observations
  70. GRB 061102B: Swift detection of a possible burst
  71. GRB 061102: Swift detection of a burst
  72. GRB 061028: VLA Observation
  73. GRB 061004: Swift/XRT Astrometry Correction
  74. GRB 060801: Swift/XRT Astrometry Correction
  75. GRB 061028: Futher P200 Observations
  76. GRB 061028: P200 Observations
  77. GRB 061028: SARA upper limit
  78. GRB 061028: z band imaging
  79. GRB 061028: Swift/UVOT Observations
  80. GRB 061028, Swift-BAT refined analysis
  81. GRB 061028: TAROT Calern observatory optical observations
  82. GRB 061028: Swift detection of a burst
  83. GRB 061027, Swift refined analysis of a possible burst
  84. GRB 061027: Swift detection of a possible burst
  85. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  86. GRB061025: Swift/UVOT observations
  87. GRB 061025: REM observations
  88. GRB 061025: ROTSE-III Optical Limits
  89. Konus-Wind observation of GRB 061021
  90. GRB 061021: Swift-XRT refined analysis
  91. GRB 061021: Swift/UVOT Observation
  92. GRB 061021: Swift detection of a burst
  93. GRB060904b: optical observations
  94. GRB 061019: SARA upper limit
  95. GRB 061019: Swift/UVOT upper limit
  96. GRB 061019, Swift-BAT refined analysis
  97. GRB 061019: TAROT La Silla observatory optical observations
  98. GRB 061019: REM K-band candidate afterglow
  99. GRB 061007: Suzaku/WAM observation of the prompt emission
  100. GRB 061006: astrometry-corrected XRT position

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