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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"

19386 results found.

  1. GRB050202: Radio Observations
  2. GRB 050202: Short burst detected by Swift-BAT
  3. GRB 050128 Optical observation with REM
  4. SGR1806-20: Swift-BAT detection of a large normal burst
  5. GRB 050128: near-infrared observations with REM
  6. GRB050128,optical observations
  7. GRB050126: Updated Swift XRT Position
  8. GRB 050126: Radio Observations
  9. GRB 050128: Swift XRT prompt afterglow position
  10. GRB050126: MASTER optical limit for KECK OT
  11. GRB050126: MASTER optical observations
  12. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  13. GRB 050124 I-band observation
  14. GRB050124,optical observation
  15. GRB050124: Updated Swift XRT Position and Fluxes
  16. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  17. GRB050123,optical observation
  18. GRB 050123: KAIT observations
  19. GRB050117a: Refined analysis
  20. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  21. GRB050117: optical observation
  22. GRB050117: MASTER optical observations
  23. MASTER:GRB050117 SWIFT
  24. GRB050117: Swift XRT Position
  25. Triangulation of Short Hard GRB050112 (large error box)
  26. SGR1806-20: Swift-BAT observations of two additional bursts
  27. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  28. Further VLA observations of SGR 1806-20
  29. ATCA observations of SGR 1806-20
  30. SGR 1806-20, RHESSI observations of the 041227 giant flare
  31. Third epoch observations of SGR 1806-20 with VLA
  32. Second Epoch VLA observations of SGR 1806-20
  33. Second-epoch VLA observations of SGR 1806-20
  34. GRB 041217: Optical observations
  35. The giant outburst from SGR 1806-20
  36. GRB041228: Swift-BAT detection of a burst
  37. GRB041219; RXTE ASM Observations
  38. NIR Observations of GRB 041219
  39. GRB041226: ROTSE-III Optical Observations
  40. GRB041223: decay of the afterglow
  41. GRB041224: ROTSE-III Optical Observations
  42. GRB 041224: near-infrared observations with REM
  43. GRB 041223 Fluence measured by Swift-BAT
  44. GRB041223: optical and NIR observations with REM
  45. GRB 041219: TAROT optical observations
  46. GRB 041218: TAROT optical observations
  47. GRB 041223: J-band observations of the afterglow
  48. GRB 041219c: PROMPT Observations
  49. GRB041223: ROTSE-III Optical Observations
  50. GRB041223: Swift-BAT detection of a bright long burst
  51. Very high activity of SGR 1806-20
  52. GRB 041218 Optical Observations
  53. GRB041219: Continued NIR Observations
  54. GRB041219b: A Swift-BAT burst
  55. GRB 041219 ,optical observation
  56. GRB 041219: Radio Afterglow Detection
  57. GRB 041218 : Radio Observations
  58. GRB 041218: R-band optical observations
  59. GRB041218: optical observations
  60. GRB041219: Confirmed NIR Afterglow
  61. Swift-BAT detection of the bright long burst GRB041219
  62. GRB 041219: Infrared Afterglow Candidate
  63. GRB041219, BVRcIc field calibration
  64. GRB 041219: Infrared Afterglow Candidate
  65. GRB041218, BVRcIc field calibration
  66. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  67. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  68. GRB 041217: PROMPT Observations
  69. GRB041217: NIR and optical observations with REM
  70. GRB041217: Infrared Observations
  71. GRB041217: The First GRB Located On-Board Swift
  72. GRB041211: Faulkes Telescope continued optical monitoring
  73. Optical transient (GRB?) in Lynx
  74. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  75. GRB041211: RAPTOR observations
  76. GRB041211: Ashra Prototype optical observation
  77. GRB041211, BVRcIc field calibration
  78. GRB041211,optical observation
  79. GRB 041211: Infrared Observations
  80. GRB 041211: KAIT observations
  81. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  82. GRB041015: Near-Infrared observations
  83. GRB 040924: Afterglow Color
  84. GRB 041006: GETS Optical Afterglow Observation
  85. Summary of the recent bursts from SGR 1806-20
  86. GRB 041006: Optical Observations
  87. GRB041006, late-time optical photometry
  88. GRB041006: RTT150 Optical Observations
  89. Bright bursts from SGR1806-20
  90. GRB 041016: BOOTES-2 simultaneous observation
  91. GRB041006: RTT150 Optical Observations
  92. GRB041016,optical observation
  93. GRB 041016: Optical limits
  94. GRB 041016:Optical limit during first minute
  95. GRB 041016: Optical limit
  96. GRB 041015 R band observations
  97. GRB040924, BVRcIc field calibration
  98. GRB041015,optical observation
  99. GRB041006: Fading X-ray Afterglow Observed with Chandra
  100. GRB041006: Optical observations and Potential host galaxy

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