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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"

21769 results found.

  1. GRB 050123: KAIT observations
  2. GRB050117a: Refined analysis
  3. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  4. GRB050117: optical observation
  5. GRB050117: MASTER optical observations
  6. MASTER:GRB050117 SWIFT
  7. GRB050117: Swift XRT Position
  8. Triangulation of Short Hard GRB050112 (large error box)
  9. SGR1806-20: Swift-BAT observations of two additional bursts
  10. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  11. Further VLA observations of SGR 1806-20
  12. ATCA observations of SGR 1806-20
  13. SGR 1806-20, RHESSI observations of the 041227 giant flare
  14. Third epoch observations of SGR 1806-20 with VLA
  15. Second Epoch VLA observations of SGR 1806-20
  16. Second-epoch VLA observations of SGR 1806-20
  17. GRB 041217: Optical observations
  18. The giant outburst from SGR 1806-20
  19. GRB041228: Swift-BAT detection of a burst
  20. GRB041219; RXTE ASM Observations
  21. NIR Observations of GRB 041219
  22. GRB041226: ROTSE-III Optical Observations
  23. GRB041223: decay of the afterglow
  24. GRB041224: ROTSE-III Optical Observations
  25. GRB 041224: near-infrared observations with REM
  26. GRB 041223 Fluence measured by Swift-BAT
  27. GRB041223: optical and NIR observations with REM
  28. GRB 041219: TAROT optical observations
  29. GRB 041218: TAROT optical observations
  30. GRB 041223: J-band observations of the afterglow
  31. GRB 041219c: PROMPT Observations
  32. GRB041223: ROTSE-III Optical Observations
  33. GRB041223: Swift-BAT detection of a bright long burst
  34. Very high activity of SGR 1806-20
  35. GRB 041218 Optical Observations
  36. GRB041219: Continued NIR Observations
  37. GRB041219b: A Swift-BAT burst
  38. GRB 041219 ,optical observation
  39. GRB 041219: Radio Afterglow Detection
  40. GRB 041218 : Radio Observations
  41. GRB 041218: R-band optical observations
  42. GRB041218: optical observations
  43. GRB041219: Confirmed NIR Afterglow
  44. Swift-BAT detection of the bright long burst GRB041219
  45. GRB 041219: Infrared Afterglow Candidate
  46. GRB041219, BVRcIc field calibration
  47. GRB 041219: Infrared Afterglow Candidate
  48. GRB041218, BVRcIc field calibration
  49. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  50. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  51. GRB 041217: PROMPT Observations
  52. GRB041217: NIR and optical observations with REM
  53. GRB041217: Infrared Observations
  54. GRB041217: The First GRB Located On-Board Swift
  55. GRB041211: Faulkes Telescope continued optical monitoring
  56. Optical transient (GRB?) in Lynx
  57. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  58. GRB041211: RAPTOR observations
  59. GRB041211: Ashra Prototype optical observation
  60. GRB041211, BVRcIc field calibration
  61. GRB041211,optical observation
  62. GRB 041211: Infrared Observations
  63. GRB 041211: KAIT observations
  64. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  65. GRB041015: Near-Infrared observations
  66. GRB 040924: Afterglow Color
  67. GRB 041006: GETS Optical Afterglow Observation
  68. Summary of the recent bursts from SGR 1806-20
  69. GRB 041006: Optical Observations
  70. GRB041006, late-time optical photometry
  71. GRB041006: RTT150 Optical Observations
  72. Bright bursts from SGR1806-20
  73. GRB 041016: BOOTES-2 simultaneous observation
  74. GRB041006: RTT150 Optical Observations
  75. GRB041016,optical observation
  76. GRB 041016: Optical limits
  77. GRB 041016:Optical limit during first minute
  78. GRB 041016: Optical limit
  79. GRB 041015 R band observations
  80. GRB040924, BVRcIc field calibration
  81. GRB041015,optical observation
  82. GRB041006: Fading X-ray Afterglow Observed with Chandra
  83. GRB041006: Optical observations and Potential host galaxy
  84. GRB041006, BVRcIc field calibration
  85. GRB 041006: SARA afterglow observations
  86. GRB041006, optical observation in CrAO
  87. Search for SN light in XRF 040912 with MEGACAM
  88. GRB 041006: BR observations with VATT
  89. GRB041006 (= H3570): Chandra Observations In Progress
  90. GRB041006, optical I observation
  91. ROTSE-IIIa Observations of GRB 041006
  92. GRB041006: MASTER optical observations
  93. GRB041006,optical observation
  94. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  95. GRB041006: Fading of optical afterglow candidate
  96. GRB 041006: Optical afterglow candidate
  97. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  98. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  99. radio observations, GRB 040924
  100. GRB040929,optical observation

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