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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"

23417 results found.

  1. GRB 060510: Swift detection of a burst with optical transient
  2. GRB060507: optical afterglow detection
  3. GRB060502B: improvement in the XRT afterglow position
  4. GRB 060507: BART limit
  5. GRB 060505: PROMPT Observations
  6. GRB 060507: MDM Optical Upper Limit
  7. GRB 060507: Swift detection of a burst
  8. GRB060505: Swift/UVOT Observations
  9. GRB060425: new MASTER survey method
  10. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  11. GRB 060505: Swift XRT afterglow canditate position
  12. GRB 060502b: Second epoch Gemini observations
  13. GRB 060428B: spectroscopy
  14. GRB 060502B: optical observations
  15. GRB 060502B: AROMA refined photometric calibration
  16. GRB 060502B MDM Follow-up Observation
  17. GRB 060502b: Gemini imaging and spectroscopy
  18. GRB060502A, optical observation
  19. GRB 060502B: Swift/UVOT upper limits
  20. GRB 060502A: Swift/UVOT source detection
  21. GRB 060429: Refined IPN error box and Konus-Wind spectrum
  22. GRB 060502B: AROMA optical observations
  23. GRB 060502B: Refined analysis of the Swift-BAT short burst
  24. Short GRB 060502B: Tautenburg Observation
  25. GRB 060502A: TTT Observations
  26. GRB 060501: P60 Observations and Candidate Retraction
  27. GRB 060502B: Xinglong optical observation
  28. GRB 060502B: Swift detection of a short burst
  29. GRB060501: Swift UVOT followup observations
  30. GRB060502: Super-LOTIS Observations
  31. GRB 060502: P60 Afterglow Confirmation
  32. GRB 060502: Swift detection of a burst with an optical counterpart
  33. GRB060501: P60 imaging and afterglow candidate
  34. GRB 060501: ROTSE-III Optical Limits
  35. GRB 060501: Swift detection of a burst
  36. IPN triangulation of GRB060429 (short/hard)
  37. GRB060428B - SDSS Pre-Burst Observations
  38. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  39. GRB 060428B: MDM Observations
  40. GRB 060428A: PROMPT Observations
  41. GRB060428B: Swift XRT Team refined analysis
  42. GRB 060427B: IPN localization of a short hard burst
  43. GRB 060428B: Refined analysis of the Swift-BAT burst
  44. GRB 060428B: Xinglong I-band limit
  45. GRB 060428B: KAIT observations
  46. GRB 051117A: Bright host galaxy not confirmed
  47. GRB060428A: Swift/UVOT observations.
  48. GRB060428B, optical observation
  49. GRB 060428b : Kiso R-band limit
  50. GRB060427:MASTER optical limit
  51. GRB 060428b: Optical afterglow candidate
  52. GRB 060428B: Swift detection of a burst
  53. GRB 060427: NIR observations
  54. GRB060427: Xinglong optical Observations
  55. GRB 060428: Swift detection of a burst
  56. GRB 060427: Swift/UVOT upper limits.
  57. GRB060425:MASTER survey observations
  58. GRB 060427, optical observation
  59. GRB 060427: Swift detection of a burst
  60. GRB 060424: Swift detection of a burst
  61. GRB 060421: TTT Observations
  62. Swift-BAT detection of Mrk 421
  63. GRB060421: Swift/UVOT observations
  64. GRB 060421: Swift-XRT refined analysis
  65. GRB 060418: prediction of t_break
  66. Konus-Wind observation of GRB 060418
  67. GRB(?)060421:MASTER optical limit
  68. GRB(?) 060421: Swift detection of a burst
  69. GRB 060418: Radio Observations
  70. GRB060418, BVRcIc field calibration
  71. GRB060418: Swift/UVOT Observations
  72. GRB060418: Optical Observations
  73. GRB 060418: FRAM early afterglow observation
  74. VLT/UVES observations of GRB060418
  75. GRB 060418, SMARTS continuing afterglow observations
  76. GRB 060418, SMARTS optical/IR afterglow observations
  77. GRB060418 : LT optical afterglow observation
  78. GRB 060418: REM candidate afterglow
  79. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  80. GRB060413: Swift/UVOT upper limits
  81. GRB 060413: REM NIR Observations
  82. SGR 1900+14: Swift detection of an outburst
  83. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  84. GRB060403: optical observations
  85. GRB 060403 Optical observations
  86. GRB 060403: MITSuME optical observation
  87. GRB060403: Optical Limit
  88. GRB 060403: Swift/UVOT upper limits
  89. SGR 1900+14: BAT observations
  90. GRB 060403: Refined analysis of the Swift-BAT burst
  91. GRB 060403: Swift detection of a burst
  92. HETE trigger H4044: RTT150 optical observations
  93. GRB060331: Swift/UVOT upper limits
  94. Swift XRT observations of the HETE transient H4043
  95. H4043, an unusual high-energy transient observed by HETE
  96. GRB 060322: LNA optical limit
  97. INTEGRAL and XMM ToO observations of SGR1900+14
  98. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  99. SGR 1900+14: Swift-BAT detection of a bright outburst
  100. GRB 060323 : WIDGET simultaneous optical observations

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