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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21795 results found.

  1. VLA detection of GRB 061222A
  2. GRB070103: APO SPIcam i' and z' limits
  3. GRB070103: KPNO 4m+FLAMINGOS J limit
  4. GRB 070103: Swift/UVOT Upper limits
  5. GRB 070103: NOT observations
  6. GRB 070103: TAROT Calern observatory optical observations
  7. erratum : SDSS Pre-burst Observations of GRB061126
  8. Konus-Wind observation of GRB 061222A
  9. GRB 061210: Swift/XRT Astrometry Correction
  10. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  11. GRB 061222A: Xinglong Optical Limit
  12. GRB 061222A: Gemini Afterglow Candidate
  13. GRB 061222B, Swift-BAT refined analysis
  14. GRB061222A Swift/UVOT: Upper Limits
  15. GRB 061222B: Swift/UVOT Upper limits
  16. GRB 061222B: Observation with the KANATA 1.5m telescope
  17. GRB 061222A: Observation with the KANATA 1.5m telescope
  18. GRB 061222B: BOOTES-IR optical observations
  19. GRB 061222B: SARA upper limit
  20. GRB 061222B: REM NIR/optical observations
  21. GRB 061222B: TAROT La Silla observatory optical observations
  22. GRB 061222B: Swift detection of a burst
  23. GRB 061222A: Prompt ROTSE-III Optical Limits
  24. GRB 061222: Swift detection of a burst
  25. GRB 061218: TAROT La Silla observatory optical observations
  26. GRB 061217: TAROT Calern observatory optical observations
  27. GRB 061218: TORTOREM optical upper limits
  28. GRB 061218, Swift-BAT refined analysis
  29. GRB061217: VLT NIR observations
  30. GRB 061218, SMARTS optical/IR observations
  31. GRB 061218: REM prompt observations
  32. Swift triggers (#251863) on a possible burst
  33. GRB061217: Swift/UVOT refined analysis.
  34. GRB 061217: Magellan Observations
  35. GRB 061217: REM prompt observations
  36. GRB 061217: ROTSE-III Optical Limits
  37. GRB061210: Swift/UVOT observations
  38. GRB 061210: Swift XRT analysis - Possible counterparts
  39. GRB 061214(?): ROTSE-III Optical Limits
  40. GRB 061210: Suzaku WAM observation of the prompt emission
  41. GRB 061210: Gemini/GMOS Observations
  42. GRB 061126: Radio Observations
  43. GRB061210: Radio Observations
  44. GRB 061202: Suzaku WAM observation of the prompt emission
  45. GRB 061210, Swift-BAT refined analysis of the SHB
  46. Optical Afterglow observations of GRB 061126
  47. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  48. GRB 061202: TORTOREM optical upper limits
  49. GRB 061201: VLT optical decay
  50. GRB 061201: SOAR Confirmation of Candidate Afterglow
  51. GRB061202: FRAM early follow-up limit
  52. GRB061202 optical limit by "Pi of the Sky"
  53. Konus-Wind observation of GRB 061201
  54. GRB061202: optical/NIR observations with REM
  55. GRB061202: Swift/UVOT Upper Limits
  56. GRB 061202, Swift-BAT refined analysis
  57. GRB 061202: Swift detection of a burst
  58. GRB 061201: VLT optical observations
  59. INT+WFC observations of GRB 061126
  60. GRB 061126: Early Super-LOTIS Observations
  61. RHESSI Spectrum of GRB061126
  62. GRB061126: Optical afterglow observations from MIRO
  63. GRB061126: Optical afterglow observations from MIRO
  64. GRB 061126 : SDSS Pre-Burst Observations
  65. GRB 061126: Swift/UVOT Observations
  66. GRB 061126: Early Detection of the IR Afterglow
  67. GRB 061126: Swift detection of a burst
  68. GRB 061122: Candidate Optical Afterglow
  69. GRB061122: Swift/UVOT Optical Observations
  70. GRB 061121: ART detection in Ic
  71. GRB061121: P60 Observations
  72. Radio detection of GRB 061121
  73. GRB061122: Swift-XRT position
  74. Konus-Wind observation of GRB 061122
  75. RHESSI Spectrum of GRB061121
  76. Konus-Wind and Konus-A observations of GRB 061121
  77. Swift-BAT trigger 239987 is not a GRB
  78. GRB 061121: Swift/UVOT Observations
  79. GRB 061121, Swift-BAT refined analysis
  80. GRB061121, optical observation
  81. GRB 061121: Optical observation at the KANATA 1.5m telescope
  82. GRB 061121: Swift detection of a bright burst with an optical counterpart
  83. GRB 060605: NIR Observations
  84. GRB 050915B: optical afterglow
  85. Swift/UVOT Upper Limits for GRB061110b
  86. Swift/UVOT Upper Limits for GRB061110a
  87. GRB 061110B, Swift-BAT refined analysis
  88. GRB061110B: Optical observations at Crni Vrh
  89. GRB 061110A, Swift-BAT refined analysis
  90. GRB 061110B: TAROT Calern observatory optical observations
  91. GRB 061110B: Swift detection of a burst
  92. GRB 061110: Candidate confirmed
  93. GRB 061110: ROTSE-III Optical Limits
  94. GRB 061110: Swift detection of a burst
  95. GRB061110A - Optical Non-detection
  96. GRB 061109: TAROT Calern observatory optical observations
  97. GRB 061027: TAROT La Silla observatory optical observations
  98. GRB 061028: Swift/XRT Astrometry Correction
  99. GRB 061102: Swift/UVOT Magnitude Upper Limits
  100. GRB061102B: Super-LOTIS observations

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