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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"

28071 results found.

  1. GRB 060510B: Super-LOTIS Observations
  2. GRB 060510b: NIR observations
  3. GRB 060510B: MDM Observations and candidate OT
  4. GRB 060510B: Swift detection of a burst
  5. GRB 060510: Swift detection of a burst with optical transient
  6. GRB060507: optical afterglow detection
  7. GRB060502B: improvement in the XRT afterglow position
  8. GRB 060507: BART limit
  9. GRB 060507: Swift/UVOT Upper Limits
  10. GRB 060507: Swift XRT Team Refined Analysis
  11. GRB 060507: MDM Optical Upper Limit
  12. GRB060507: Swift XRT position
  13. GRB 060507: Swift detection of a burst
  14. GRB060505: Swift/UVOT Observations
  15. GRB 060505: Swift XRT Team Refined Analysis
  16. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  17. GRB 060505: Swift XRT afterglow canditate position
  18. GRB 060502b: Second epoch Gemini observations
  19. GRB 060505: Swift-BAT detection of a weak burst
  20. GRB 060428B: spectroscopy
  21. GRB 060502B: optical observations
  22. GRB 060502B MDM Follow-up Observation
  23. GRB 060502b: Gemini imaging and spectroscopy
  24. GRB060502A, optical observation
  25. GRB 060502B: Swift/UVOT upper limits
  26. GRB 060502A: Swift/UVOT source detection
  27. GRB 060502B: MDM Optical Observation
  28. GRB060502B: Swift XRT Team refined analysis
  29. Short GRB 060502B: Tautenburg Observation
  30. GRB 060502A: TTT Observations
  31. GRB060502B: correction to XRT position
  32. GRB 060501: P60 Observations and Candidate Retraction
  33. GRB 060502B: Xinglong optical observation
  34. GRB 060502B: MASTER optical observations
  35. GRB 060502B: Swift detection of a short burst
  36. GRB060502: Swift-XRT refined analysis
  37. GRB060502: Gemini spectroscopy
  38. GRB 060502: APO Spectroscopic Observations
  39. GRB060501: Swift UVOT followup observations
  40. GRB060502: Super-LOTIS Observations
  41. GRB 060502: P60 Afterglow Confirmation
  42. GRB 060502: Swift detection of a burst with an optical counterpart
  43. GRB 060501: MDM Observations
  44. GRB060501: P60 imaging and afterglow candidate
  45. GRB060501: Swift XRT position
  46. GRB 060501: Swift detection of a burst
  47. GRB060428B: optical observation
  48. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  49. GRB 060428B: MDM Observations
  50. GRB060428B: Swift XRT Team refined analysis
  51. GRB 060428B: KAIT observations
  52. GRB 051117A: Bright host galaxy not confirmed
  53. GRB060428A: Swift/UVOT observations.
  54. GRB 060428b : Kiso R-band limit
  55. GRB 060428b: Optical afterglow candidate
  56. GRB060428A: Swift XRT Team refined analysis
  57. GRB 060428B: Swift detection of a burst
  58. GRB 060427: NIR observations
  59. GRB 060428: Swift detection of a burst
  60. GRB 060427: NOT observations
  61. GRB 060427: Swift/UVOT upper limits.
  62. GRB060427: Swift XRT Team refined analysis
  63. GRB060418: Swift XRT Team Further Refined Analysis
  64. GRB 060427: Swift detection of a burst
  65. GRB060424: optical afterglow detection
  66. GRB060418: Further Analysis of MIKE Spectroscopy
  67. GRB 060424: Swift detection of a burst
  68. OT 060420: Likely Not a New Cosmic Transient
  69. Swift-BAT detection of Mrk 421
  70. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  71. GRB060421: Swift/UVOT observations
  72. GRB 060421: Swift-XRT refined analysis
  73. GRB060418: optical observations
  74. Konus-Wind observation of GRB 060418
  75. GRB(?)060421:MASTER optical limit
  76. GRB(?)060421 : XRT position
  77. GRB(?) 060421: Swift detection of a burst
  78. Erratum of GCN 4983 for GRB 060418 IR follow-up
  79. GRB 060418 : IR afterglow observations
  80. GRB 060418 : Lulin Optical follow-up
  81. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  82. GRB 060418: Radio Observations
  83. GRB060418, BVRcIc field calibration
  84. GRB060418: Swift/UVOT Observations
  85. GRB060418: Optical Observations
  86. GRB 060418: FRAM early afterglow observation
  87. GRB 060418: Refined Analysis of the Swift-BAT burst
  88. VLT/UVES observations of GRB060418
  89. GRB060418: Swift XRT Team Refined Analysis
  90. GRB 060418, SMARTS continuing afterglow observations
  91. GRB 060418: PROMPT Detections
  92. GRB 060418, SMARTS optical/IR afterglow observations
  93. GRB060418: Magellan/MIKE Spectroscopic Redshift
  94. GRB060418 : LT optical afterglow observation
  95. GRB 060418: REM candidate afterglow
  96. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  97. GRB060413: Swift/UVOT upper limits
  98. GRB 060413: REM NIR Observations
  99. SGR 1900+14: Swift detection of an outburst
  100. GRB 060413: Watcher UBVR observations

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