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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"

24683 results found.

  1. GRB 050202: Short burst detected by Swift-BAT
  2. GRB 050128 Optical observation with REM
  3. SGR1806-20: Swift-BAT detection of a large normal burst
  4. GRB 050128: near-infrared observations with REM
  5. GRB050128,optical observations
  6. GRB050128 Swift-BAT observations
  7. GRB 050128: Swift XRT prompt afterglow position
  8. GRB050126: MASTER optical limit for KECK OT
  9. GRB050126: Burst Parameters Measured by BAT
  10. GRB050126: MASTER optical observations
  11. GRB 050124 I-band observation
  12. GRB050124,optical observation
  13. GRB 050124 : Lulin R-band follow-up observation
  14. GRB050124: Updated Swift XRT Position and Fluxes
  15. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  16. GRB050124: Refined BAT position, spectral and fluence information
  17. GRB 050123 : I-band follow-up observation
  18. GRB050123,optical observation
  19. GRB 050123: KAIT observations
  20. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  21. GRB050117: Refined XRT position
  22. GRB050117: MASTER optical observations
  23. MASTER:GRB050117 SWIFT
  24. GRB050117: Swift XRT Position
  25. Triangulation of Short Hard GRB050112 (large error box)
  26. SGR 1806-20: Further VLA Observations
  27. SGR1806-20: Swift-BAT observations of two additional bursts
  28. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  29. Further VLA observations of SGR 1806-20
  30. SGR 1806-20 and extragalactic short-duration GRBs
  31. Further ATCA observations of SGR 1806-20
  32. Fourth Epoch VLA observations of SGR 1806-20
  33. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  34. ATCA observations of SGR 1806-20
  35. SGR 1806-20, RHESSI observations of the 041227 giant flare
  36. Third epoch observations of SGR 1806-20 with VLA
  37. Second Epoch VLA observations of SGR 1806-20
  38. Second-epoch VLA observations of SGR 1806-20
  39. SGR1806 VLA Observations
  40. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  41. GRB 041217: Optical observations
  42. GRB041228: Swift-BAT detection of a burst
  43. GRB041219; RXTE ASM Observations
  44. NIR Observations of GRB 041219
  45. GRB041226: Swift-BAT detection of a burst
  46. GRB041223: decay of the afterglow
  47. GRB 041224: near-infrared observations with REM
  48. GRB 041223 Fluence measured by Swift-BAT
  49. GRB041223: optical and NIR observations with REM
  50. Swift-BAT Time History of GRB041219
  51. GRB 041219: TAROT optical observations
  52. GRB 041218: TAROT optical observations
  53. GRB 041223: J-band observations of the afterglow
  54. GRB 041219c: PROMPT Observations
  55. GRB041223: Swift-BAT detection of a bright long burst
  56. GRB 041218: optical observations
  57. GRB 041219 : optical follow-up observations
  58. Deep RAPTOR observations during GRB 041219
  59. GRB 041218 Optical Observations
  60. GRB041219: Continued NIR Observations
  61. GRB 041219 ,optical observation
  62. GRB 041219: Radio Afterglow Detection
  63. GRB 041218 : Radio Observations
  64. GRB 041218: R-band optical observations
  65. GRB041218: optical observations
  66. GRB041219: Confirmed NIR Afterglow
  67. Swift-BAT detection of the bright long burst GRB041219
  68. GRB 041219: Infrared Afterglow Candidate
  69. GRB041219, BVRcIc field calibration
  70. GRB 041219: Infrared Afterglow Candidate
  71. GRB041218, BVRcIc field calibration
  72. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  73. GRB 041219 - A long GRB detected by INTEGRAL
  74. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  75. GRB 041217: PROMPT Observations
  76. GRB 041217: LCO40 Optical Observations and Possible Candidates
  77. GRB 041218 - A long GRB detected by integral
  78. GRB041217: NIR and optical observations with REM
  79. GRB041217: Infrared Observations
  80. GRB041217: The First GRB Located On-Board Swift
  81. GRB041211: Faulkes Telescope continued optical monitoring
  82. Optical Transient in Lynx not a GRB
  83. Optical transient (GRB?) in Lynx
  84. GRB041211: RAPTOR observations
  85. GRB041211: Ashra Prototype optical observation
  86. GRB041211, BVRcIc field calibration
  87. GRB041211,optical observation
  88. GRB 041211: Infrared Observations
  89. GRB 041211: KAIT observations
  90. GRB 041211: Optical follow-up in East Asian region
  91. Triangulation of short GRB 041116 (large error box)
  92. GRB 040924: Afterglow Color
  93. GRB 041006: GETS Optical Afterglow Observation
  94. Summary of the recent bursts from SGR 1806-20
  95. GRB 041006: Optical Observations
  96. GRB041006, late-time optical photometry
  97. GRB041006: RTT150 Optical Observations
  98. HST Observations: XRF 040701 and 040812
  99. Bright bursts from SGR1806-20
  100. GRB 041016: BOOTES-2 simultaneous observation

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