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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"

11761 results found.

  1. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  2. GRB 050626 optical observations
  3. GRB 050626: Swift XRT observations
  4. GRB 050408: ARC 3.5-meter NIR Observations
  5. GRB050701: Swift-BAT Refined analysis
  6. GRB 050626 - a long GRB detected with INTEGRAL
  7. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  8. Konus-Wind observation of an intermediate burst from SGR 1806-20
  9. GRB 050607: Optical decay and spectral slope
  10. Optical Afterglow of GRB 050607
  11. Konus-Wind observation of GRB 050603
  12. GRB050528: updated Liverpool Telescope limits
  13. GRB 050525: RTT150, Optical observations
  14. GRB 050525: MITSuME Optical Observation in VRI
  15. GRB050525: Super-LOTIS observations
  16. GRB 050525A: Swift-BAT refined analysis
  17. GRB050525: Optical observations
  18. Konus-Wind observation of GRB 050525
  19. INTEGRAL detection of GRB 050525
  20. GRB 050525, infrared observations
  21. GRB 050525: Optical observation
  22. GRB050525: ROTSE-III Refined Analysis
  23. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  24. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  25. XRF050522: NIR observations of XRT candidate
  26. XRF 050522: Swift XRT refined analysis
  27. GRB 050509A: Further I-band imaging
  28. GRB050522,optical observation
  29. GRB050520,optical observation
  30. GRB050509b: optical observations
  31. XRF 050522: Swift XRT observation
  32. XRF050522: Optical Observations
  33. XRF 050522 detected with INTEGRAL
  34. GRB 050520: Swift XRT refined analysis
  35. XRF050509C: Chandra Afterglow Detection
  36. XRF 050509c: Swift XRT Upper Limit
  37. GRB050520: Liverpool Telescope follow-up
  38. GRB 050520 - A long GRB detected with INTEGRAL
  39. Swift-BAT trigger 122203 is not a real GRB
  40. GRB 050509B and short GRB-SN association? (corrected)
  41. GRB 050509B and short GRB-SN association?
  42. GRB050509b, Bok telescope B-band imaging
  43. Chandra observation of GRB 050509b
  44. GRB 050509b: RAPTOR deep, early limits.
  45. GRB 050509a: Swift-BAT refined analysis
  46. GRB 050509c: ROTSE-III Optical Limits
  47. GRB 050509A: Optical observations
  48. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  49. GRB 050509B: ROTSE-III Optical Limits
  50. GRB 050509a: Swift XRT Position
  51. Swift-BAT detection of GRB 050507
  52. GRB 050502a: Swift XRT Upper Limit
  53. GRB050416A : 1 GHz limit from GMRT
  54. GRB050505 Swift-BAT refined analysis
  55. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  56. GRB050502b: Afterglow Confirmation
  57. GRB 050504, R band Observations
  58. GRB 050504: A long GRB detected with INTEGRAL
  59. Renewal of SGR 1806-20 activity
  60. GRB050502A: Optical Observations
  61. GRB 050502: INTEGRAL results
  62. GRB 050502 - A long GRB detected with INTEGRAL
  63. GRB 050421: SLOTIS observations
  64. GRB 050421: IR Observations
  65. GRB 050421: ROTSE-III Optical Limits
  66. GRB 050421: NIR observations
  67. Swift Detection of GRB050421
  68. GRB050326: analysis of the XMM-Newton observation
  69. GRB 050412: Chandra observations
  70. Swift-BAT detection of the bright and long GRB 050418
  71. GRB 050416B: optical observations
  72. GRB 050416: Swift-BAT refined analysis
  73. GRB 050416: Radio observations
  74. GRB 050408: RTT150 optical observations
  75. GRB050408: optical observation
  76. GRB 050412 : XingLong optical observation
  77. GRB050412: optical limit before and during GRB
  78. GRB050412: ROTSE-III Optical Limits
  79. GRB 050410, optical observations
  80. GRB 050410, optical observations
  81. GRB 050408: Swift XRT measurement of possible jet break
  82. Swift-BAT detection of GRB 050410
  83. GRB 050410: Swift XRT Position
  84. GRB 050408: Optical limit at 20 min after the burst
  85. GRB 050408, optical observations
  86. GRB 050408,optical observation
  87. GRB 050408: Mercator Optical Observations
  88. GRB 050408, optical observations
  89. GRB 050408: ROTSE-III Optical Limits
  90. Konus-Wind observation of GRB 050401
  91. GRB 050401 BAT refined analysis
  92. Swift Trigger 113225: P60 Observations
  93. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  94. Swift-BAT detection of GRB 050401
  95. GRB 050401: Prompt XRT position
  96. GRB050331: No Afterglow Detected
  97. Swift-BAT detection of GRB 050331
  98. Konus-Wind observation of GRB 050326
  99. GRB050326: optical limit 33min before GRB
  100. GRB050319, optical observations

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