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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"

36143 results found.

  1. GRB 050306: TAROT optical observations
  2. GRB 050306,optical observation
  3. GRB 050306: Swift-BAT detection of a long burst
  4. GRB 050126: Confirmation of the NIR afterglow candidate
  5. PROMPT VRcIc Observations of GRB 050223
  6. XRF/GRB 050215B: Radio Observations
  7. XMM-Newton Images of GRB 050223
  8. GRB 050219b: candidate NIR afterglow
  9. IBAS GRB Alert #2321
  10. GRB 050223: optical observations
  11. INTEGRAL detection of GRB 050223
  12. GRB 050223 : Planned XMM-Newton observation
  13. GRB050223: ROTSE-III Optical Observations
  14. GRB 050223 Swift/BAT detection of a burst
  15. GRB 050223: Swift XRT Position
  16. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  17. GRB 050219b: CORRECTION to refined XRT position
  18. GRB 050219a: Optical observations from LCO
  19. GRB 050219b: Optical and near-IR observations from LCO
  20. GRB 050219b: Refined XRT position
  21. GRB 050219b: Swift-BAT detection of a burst
  22. GRB 050219b: CORRECTION: Swift XRT Position
  23. GRB 050219b: Swift XRT Position
  24. GRB 050219a, optical observations
  25. GRB 050219a: Refined XRT position
  26. GRB 050219: Swift-BAT detection of a burst
  27. GRB050215b: Swift UVOT Detection of Afterglow Emission
  28. GRB 050219: Prompt X-ray position
  29. GRB 050215B: Radio Observations
  30. GRB 050215b: XRT confirmation of IR afterglow candidate
  31. GRB050215b: P60 Optical Observations
  32. GRB 050215b: Swift XRT Source Variability
  33. GRB 050215B: candidate afterglow
  34. GRB 050215b : Lulin follow-up observation
  35. GRB 050215b, BOOTES-2 simultaneous optical observations
  36. GRB 050215B: UKIRT K-band imaging
  37. GRB 050215b: Swift XRT Observations
  38. GRB 050215b, BOOTES-1B optical limit
  39. GRB050215A: ROTSE-III Optical Observations
  40. GRB050209: TAROT optical observations
  41. GRB 050209(=U11568): Duration and spectrum
  42. short/hard GRB 050202, optical observations
  43. GRB050209: REM optical observations
  44. GRB 050209 I-band observation
  45. GRB 050209 Optical observations
  46. GRB050209: P60 Optical Observations
  47. GRB050209 (=U11568): A Long GRB Detected by HETE
  48. GRB 050209: Optical observation
  49. GRB 050128: Radio observations
  50. Further analysis of the short Swift-BAT GRB 050202
  51. GRB 050202: Second epoch radio observations
  52. GRB 050129: Optical observations
  53. GRB050202: Radio Observations
  54. GRB 050202: Optical observations with LCO40
  55. GRB 050202: Short burst detected by Swift-BAT
  56. GRB 050128 Optical observation with REM
  57. GRB 050129: a weak long GRB detected with INTEGRAL
  58. GRB050128: Faulkes Telescope South observations
  59. GRB 050124: Radio Observations
  60. GRB 050128: near-infrared observations with REM
  61. GRB050128,optical observations
  62. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  63. GRB 050126: Radio Observations
  64. GRB050128 Swift-BAT observations
  65. GRB 050128: Swift XRT prompt afterglow position
  66. GRB 050124: K-band afterglow observations
  67. GRB050126: MASTER optical limit for KECK OT
  68. GRB050126: MASTER optical observations
  69. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  70. GRB 050126: Prompt XRT detection and localization
  71. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  72. GRB 050124, SMARTS optical/IR observations
  73. GRB 050117a: Radio Observations
  74. GRB 050124 I-band observation
  75. GRB 050124: NIR Candidates from Keck/NIRC
  76. GRB050124,optical observation
  77. GRB 050124 : Lulin R-band follow-up observation
  78. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  79. GRB 050123 : I-band follow-up observation
  80. GRB050123: optical limit 1.8h before GRB
  81. GRB050123,optical observation
  82. GRB 050123: KAIT observations
  83. GRB050123: P60 Observations
  84. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  85. CFHTLS optical transient unlikely to be a GRB
  86. Unusual optical transient (GRB ???)
  87. GRB050117a: Radio Observations
  88. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  89. GRB 050117, I-band observations
  90. GRB 050117: Optical observation
  91. GRB050117: Refined XRT position
  92. GRB050117: MASTER optical observations
  93. MASTER:GRB050117 SWIFT
  94. GRB050117: Swift-BAT detection of a long multi-peaked burst
  95. Triangulation of Short Hard GRB050112 (large error box)
  96. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  97. SGR 1806-20 and extragalactic short-duration GRBs
  98. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  99. SGR 1806-20: Temporal and Spectral behavior of radio transient
  100. SGR 1806-20, RHESSI observations of the 041227 giant flare

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