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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"

26371 results found.

  1. XRF 050522: KAIT observations
  2. XRF 050522 detected with INTEGRAL
  3. GRB 050520: Swift XRT refined analysis
  4. XRF 050509c: Swift XRT Upper Limit
  5. GRB 050520: P200 Observations
  6. GRB050520: Liverpool Telescope follow-up
  7. GRB 050520: TAROT optical limit
  8. GRB 050520: VLT/ULTRACAM observations
  9. GRB 050520: OSN optical observations
  10. GRB 050520 - A long GRB detected with INTEGRAL
  11. XRF 050509C: REM NIR and Optical refined analysis
  12. GRB050502b: Early Observation
  13. GRB050509b, SDSS pre-burst observations
  14. Chandra observation of GRB 050509b
  15. GRB 050509b Milagro GeV/TeV Observations
  16. GRB050509B: Optical observations at the Very Large Telescope
  17. GRB 050509b: No Optical Variability in XRT Error Circle
  18. GRB 050509c: ROTSE-III Optical Limits
  19. GRB 050505, early TAROT observation
  20. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  21. GRB 050509b: Further Analysis of Keck LRIS Images
  22. GRB050509c: REM NIR and Optical observations
  23. GRB 050509b: Physical Properties of the Candidate Host galaxy
  24. GRB 050505: SARA Observations
  25. GRB 050509B, Optical Observations
  26. GRB 050509B: Swift/XRT refined analysis
  27. GRB050509a: Swift UVOT observations
  28. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  29. GRB 050509b: optical observations
  30. Swift Detection of GRB050509b: A short duration burst
  31. Swift Detection of the Burst GRB050509
  32. Swift-BAT detection of GRB 050507
  33. GRB 050505: early time observations
  34. GRB 050502a: Swift XRT Upper Limit
  35. GRB 050505: Further Swift UVOT observations.
  36. GRB050505: AAVSO observations
  37. GRB050416A : 1 GHz limit from GMRT
  38. GRB050505 Swift-BAT refined analysis
  39. GRB 050416b:Swift XRT afterglow upper limits
  40. GRB 050416b:Swift XRT afterglow upper limits
  41. Swift-BAT detection of GRB050505
  42. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  43. GRB050502b: Afterglow Confirmation
  44. GRB050502: P200 Observations (Correction)
  45. GRB050502: P200 Observations
  46. Swift UVOT observation of GRB 050504
  47. GRB050504: Faulkes North optical robotic limit
  48. GRB050504: P60 Observations
  49. GRB 050504: A long GRB detected with INTEGRAL
  50. GRB 050502b, Optical observations
  51. GRB050502a: P60 Observations (Correction)
  52. GRB050502a: P60 Observations
  53. Renewal of SGR 1806-20 activity
  54. GRB050502B Swift-BAT refined analysis
  55. GRB050502B: I band source in XRT error circle
  56. Retraction of Swift-BAT trigger 116145
  57. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  58. GRB050502B: Optical Limits from ANU 1m
  59. GRB 050502: Confirmed variability of the afterglow candidate +
  60. GRB 050502: PAIRITEL IR Observations
  61. GRB 050502 - A long GRB detected with INTEGRAL
  62. GRB 050401: Rc observation
  63. GRB050416a: Radio Detection
  64. Swift Detection of GRB 050422
  65. GRB 050421: SLOTIS observations
  66. GRB 050421: ROTSE-III Optical Limits
  67. GRB050421: P60 Observations
  68. GRB 050421: Optical observations at the INT
  69. Swift Detection of GRB050421
  70. GRB 050416b: Tentative Swift XRT Position
  71. GRB050326: analysis of the XMM-Newton observation
  72. GRB050418: Null Optical Observations
  73. GRB 050412: Chandra observations
  74. GRB050416A, optical observations
  75. GRB 050418: Swift-BAT refined analysis
  76. Swift-BAT detection of the bright and long GRB 050418
  77. GRB 050416: Mitsume optical observation
  78. GRB 050416B: optical observations
  79. GRB 050416: Swift/UVOT detection of afterglow emission
  80. GRB 050416: Swift-BAT refined analysis
  81. GRB 050416,optical observation
  82. GRB 050416: KAIT observations
  83. GRB050416: P200 NIR Observations
  84. Confirmation of OT for GRB050416
  85. Swift BAT/XRT Detection of GRB 050416
  86. GRB 050412: Subaru observations
  87. GRB 050408: RTT150 optical observations
  88. GRB 050412: PROMPT VRcIc Observations
  89. GRB 050408: Kuiper 1.5m observations
  90. GRB 050412: optical observations
  91. GRB 050408: refined XRT analysis, no jet break seen yet
  92. GRB 050412 : XingLong optical observation
  93. GRB 050412: Swift-BAT refined analysis
  94. GRB 050412: ANU 2.3m observations
  95. GRB 050408: SDSS Field Calibration
  96. GRB 050412: LCO Optical Observations
  97. GRB050412: P60 Observations
  98. GRB050412: optical limit before and during GRB
  99. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  100. GRB 050408: Optical limit

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