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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"

6094 results found.

  1. GRB 050724: Chandra Observations of the X-ray Afterglow
  2. GRB050713: analysis of the XMM-Newton observation
  3. GRB 050724 : Lulin early R-band monitoring observations
  4. GRB 050714a: Refined XRT analysis and afterglow confirmation
  5. GRB 050714B: refined XRT analysis
  6. GRB 050713A: XRT refined analysis
  7. GRB050712: TNG R-band observations
  8. GRB 050713b : Lulin R-band observations
  9. GRB 050713: ARC NIR Detections and Identification of Fading
  10. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  11. GRB 050626: Swift XRT observations
  12. GRB 050408: ARC 3.5-meter NIR Observations
  13. GRB 050603 - XRT data analysis of the first day
  14. GRB 050603: INTEGRAL shows it is not a short GRB
  15. GRB 050525a, infrared observations
  16. GRB 050509b: refined XRT/Chandra afterglow position analysis
  17. GRB 050525a: SARA Observations
  18. XRF050522: NIR observations of XRT candidate
  19. XRF 050522: Continued NIR P200 Monitoring
  20. XRF050522: Near-infrared Observations
  21. XRF050509C: Chandra Afterglow Detection
  22. XRF 050509c: Swift XRT Upper Limit
  23. GRB 050520: P200 Observations
  24. GRB 050520: OSN optical observations
  25. GRB 050504: Swift XRT afterglow candidate has faded
  26. Refined Chandra analysis of GRB 050509b
  27. Chandra observation of GRB 050509b
  28. GRB 050509b Milagro GeV/TeV Observations
  29. GRB 050509b: No Optical Variability in XRT Error Circle
  30. GRB 050509b: Possible Optical Counterpart
  31. GRB 050502a: Swift XRT Upper Limit
  32. GRB050505: Optical Afterglow Candidate
  33. GRB 050504, R band Observations
  34. GRB (?) 050504: IR Observations, Intriguing Source
  35. GRB050502A: Optical Observations
  36. GRB 050502: Confirmed variability of the afterglow candidate +
  37. GRB 050421: Further Analysis of IR imaging
  38. GRB 050421: IR Observations
  39. GRB050326: analysis of the XMM-Newton observation
  40. GRB050416B: IR observations
  41. GRB050416: P200 NIR Observations
  42. GRB 050412 : XingLong optical observation
  43. GRB050410 : Null detection report
  44. GRB 050408: Swift XRT measurement of possible jet break
  45. GRB 050408: SOAR UBVRc Observations
  46. GRB 050408: Swift XRT analysis
  47. GRB050408: REM NIR and Optical observation
  48. GRB 050406: early Swift XRT analysis results
  49. GRB 050402: Early observations with Swift-UVOT
  50. GRB 050326 XMM-Newton observation
  51. GRB050223: analysis of the XMM-Newton observation
  52. Swift-BAT trigger 107873: No Swift XRT counterpart
  53. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  54. GRB 050309 : Lulin R-band observation
  55. GRB 050306: REM optical-infrared observations
  56. GRB 050126: Confirmation of the NIR afterglow candidate
  57. GRB 050219b: candidate NIR afterglow
  58. GRB 050219b: Optical and near-IR observations from LCO
  59. GRB 050215b : Lulin follow-up observation
  60. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  61. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  62. GRB 050124: NIR Candidates from Keck/NIRC
  63. GRB050117: Palomar WIRC Ks-band observations
  64. GRB050117: optical observation
  65. GRB 050117, I-band observations
  66. GRB 041217: Optical observations
  67. Giant flare from SGR 1806-20 detected by INTEGRAL
  68. NIR Observations of GRB 041219
  69. GRB041226: ROTSE-III Optical Observations
  70. Swift-BAT Time History of GRB041219
  71. GRB 041219 : optical follow-up observations
  72. Swift-BAT detection of the bright long burst GRB041219
  73. GRB 041211: Infrared Observations
  74. GRB 041211: Optical follow-up in East Asian region
  75. GRB041015: Near-Infrared observations
  76. GRB 040924: Afterglow Color
  77. GRB 041006: Optical Observations
  78. GRB041006: RTT150 Optical Observations
  79. GRB041015 : Multi epoch optical observations
  80. GRB 041016: Optical limits
  81. GRB 041016:Optical limit during first minute
  82. GRB 041015: Optical Observations at Rikubetsu
  83. GRB041006: Near Infrared observations
  84. GRB 041016: Optical limit
  85. GRB041015 : Optical follow-up at Kiso
  86. GRB041006, optical observation
  87. GRB 041006: Optical afterglow candidate
  88. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  89. GRB040924: KAIT observations
  90. GRB 040924, optical follow-up
  91. XRF 040912, identification of CXO sources
  92. XRF 040916, optical follow-up
  93. GRB 040912: Optical Observations
  94. Optical observations of GRB/XRF 040912 = HETE 3557
  95. GRB040912 : Kiso Optical follow-up observation
  96. HETE 3557: Optical observations
  97. GRB040827: analysis of the XMM-Newton observation
  98. GRB 040827: 2nd epoch of Magellan K-band imaging
  99. GRB 040827: Detection of NIR afterglow
  100. GRB 040825: Optical observations

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