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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"

23403 results found.

  1. GRB 060502B: AROMA refined photometric calibration
  2. GRB 060502B MDM Follow-up Observation
  3. GRB 060502b: Gemini imaging and spectroscopy
  4. GRB060502A, optical observation
  5. GRB 060502B: Swift/UVOT upper limits
  6. GRB 060502A: Swift/UVOT source detection
  7. GRB 060429: Refined IPN error box and Konus-Wind spectrum
  8. GRB 060502B: AROMA optical observations
  9. GRB 060502B: Refined analysis of the Swift-BAT short burst
  10. Short GRB 060502B: Tautenburg Observation
  11. GRB 060502A: TTT Observations
  12. GRB 060501: P60 Observations and Candidate Retraction
  13. GRB 060502B: Xinglong optical observation
  14. GRB 060502B: Swift detection of a short burst
  15. GRB060501: Swift UVOT followup observations
  16. GRB060502: Super-LOTIS Observations
  17. GRB 060502: P60 Afterglow Confirmation
  18. GRB 060502: Swift detection of a burst with an optical counterpart
  19. GRB060501: P60 imaging and afterglow candidate
  20. GRB 060501: ROTSE-III Optical Limits
  21. GRB 060501: Swift detection of a burst
  22. IPN triangulation of GRB060429 (short/hard)
  23. GRB060428B - SDSS Pre-Burst Observations
  24. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  25. GRB 060428B: MDM Observations
  26. GRB 060428A: PROMPT Observations
  27. GRB060428B: Swift XRT Team refined analysis
  28. GRB 060427B: IPN localization of a short hard burst
  29. GRB 060428B: Refined analysis of the Swift-BAT burst
  30. GRB 060428B: Xinglong I-band limit
  31. GRB 060428B: KAIT observations
  32. GRB 051117A: Bright host galaxy not confirmed
  33. GRB060428A: Swift/UVOT observations.
  34. GRB060428B, optical observation
  35. GRB 060428b : Kiso R-band limit
  36. GRB060427:MASTER optical limit
  37. GRB 060428b: Optical afterglow candidate
  38. GRB 060428B: Swift detection of a burst
  39. GRB 060427: NIR observations
  40. GRB060427: Xinglong optical Observations
  41. GRB 060428: Swift detection of a burst
  42. GRB 060427: Swift/UVOT upper limits.
  43. GRB060425:MASTER survey observations
  44. GRB 060427, optical observation
  45. GRB 060427: Swift detection of a burst
  46. GRB 060424: Swift detection of a burst
  47. GRB 060421: TTT Observations
  48. Swift-BAT detection of Mrk 421
  49. GRB060421: Swift/UVOT observations
  50. GRB 060421: Swift-XRT refined analysis
  51. GRB 060418: prediction of t_break
  52. Konus-Wind observation of GRB 060418
  53. GRB(?)060421:MASTER optical limit
  54. GRB(?) 060421: Swift detection of a burst
  55. GRB 060418: Radio Observations
  56. GRB060418, BVRcIc field calibration
  57. GRB060418: Swift/UVOT Observations
  58. GRB060418: Optical Observations
  59. GRB 060418: FRAM early afterglow observation
  60. VLT/UVES observations of GRB060418
  61. GRB 060418, SMARTS continuing afterglow observations
  62. GRB 060418, SMARTS optical/IR afterglow observations
  63. GRB060418 : LT optical afterglow observation
  64. GRB 060418: REM candidate afterglow
  65. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  66. GRB060413: Swift/UVOT upper limits
  67. GRB 060413: REM NIR Observations
  68. SGR 1900+14: Swift detection of an outburst
  69. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  70. GRB060403: optical observations
  71. GRB 060403 Optical observations
  72. GRB 060403: MITSuME optical observation
  73. GRB060403: Optical Limit
  74. GRB 060403: Swift/UVOT upper limits
  75. SGR 1900+14: BAT observations
  76. GRB 060403: Refined analysis of the Swift-BAT burst
  77. GRB 060403: Swift detection of a burst
  78. HETE trigger H4044: RTT150 optical observations
  79. GRB060331: Swift/UVOT upper limits
  80. Swift XRT observations of the HETE transient H4043
  81. H4043, an unusual high-energy transient observed by HETE
  82. GRB 060322: LNA optical limit
  83. INTEGRAL and XMM ToO observations of SGR1900+14
  84. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  85. SGR 1900+14: Swift-BAT detection of a bright outburst
  86. GRB 060323 : WIDGET simultaneous optical observations
  87. GRB 060323: Early optical observation at Xinglong
  88. GRB 060322: Confirmation of Swift XRT afterglow
  89. SGR 1900+14: Swift detection of renewed activity
  90. GRB060323: NOT optical observations
  91. GRB 060322: IAC80 optical observations
  92. GRB 060322: Swift XRT afterglow candidate
  93. GRB060323: P60 Observations
  94. GRB 060323: Swift/UVOT Observations
  95. GRB 060323: optical afterglow confirmed
  96. GRB060323: NOT observations
  97. GRB 060323: Optical Observations
  98. GRB 060323: optical observations at TNG
  99. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  100. GRB060323, optical observation

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