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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').
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"

28041 results found.

  1. GRB 050820A: NIR photometry at the TNG
  2. GRB050925: Swift/XRT limits
  3. GRB/SGR 050925: IR Observations
  4. GRB 050922C: break in the lightcurve
  5. GRB050925: Swift UVOT upper limits
  6. Refined analysis of the Swift-BAT soft short burst
  7. GRB050925: Faulkes Telescope North R-band limit
  8. GRB050925: Swift-BAT detection of a short burst
  9. GRB050922C: TNG spectroscopic observations
  10. GRB050922B: refined XRT analysis
  11. GRB050922B: Swift UVOT early upper limits.
  12. GRB050922C: Optical Observations
  13. GRB 050922C: Swift XRT refined analysis
  14. HETE Fregate observations of GRB 050922C
  15. GRB 050922C: Swift-BAT refined analysis
  16. GRB 050922B: Swift-BAT refined analysis
  17. GRB 050922C: optical obserations
  18. GRB 050922C: NOT optical observations
  19. GRB 050922C: Swift detection of a bright burst
  20. GRB 050922B: ROTSE-III Optical Limits
  21. GRB 050922B,optical observation
  22. GRB050922B: Swift-BAT detection of a weak long burst
  23. GRB050820B: analysis of the XMM-Newton observation
  24. GRB050916: Swift/UVOT Upper Limits
  25. GRB 050916: Swift-BAT refined analysis
  26. Swift-BAT trigger 155764 is not a GRB
  27. Swift-BAT trigger 155764 is probably not a GRB
  28. Swift trigger 155764: bad XRT centroid
  29. Swift-BAT trigger 155535 is definitely not a GRB
  30. GRB050916 : Swift-XRT refined analysis
  31. GRB 050915B: Swift-BAT refined analysis
  32. GRB 050915B: Swift/UVOT Upper Limits
  33. GRB 050915a: IR Transient
  34. GRB 050915b, SMARTS optical/IR observations
  35. GRB050915B: Swift-BAT detection of a long bright burst
  36. GRB050915: Swift/UVOT upper limits
  37. GRB 050915: IR Observations
  38. GRB 050915: Swift XRT refined analysis
  39. GRB 050915: Swift-BAT refined analysis
  40. GRB 050915: Swift detection of a GRB
  41. GRB050911: Upper limit on X-ray afterglow
  42. Swift-BAT trigger 155072 ground analysis
  43. Swift-BAT trigger 155072 is probably not a GRB
  44. GRB 050908: DEIMOS spectrum and further analysis
  45. GRB 050911, optical content of Swift/XRT error box
  46. GRB 050911: Swift-BAT refined analysis
  47. GRB 050911: z~0.16 cluster in the field
  48. GRB050911: Swift-BAT detection of a long burst
  49. GRB 050910a: TAROT early optical limits
  50. WIRO observations in I of GRB 050908
  51. GRB 050906: Possible X-ray Counterpart
  52. GRB050908: Swift/UVOT Early upper limits
  53. GRB050908 : Swift-XRT refined analysis
  54. GRB 050908: Swift-BAT refined analysis
  55. GRB 050908: Optical observations
  56. GRB 050908: Optical Observations
  57. GRB 050908: Swift detection of a burst
  58. GRB 050906: Optical observations at the Very Large Telescope
  59. GRB 050904 BAT refined analysis of complete data set
  60. GRB 050904: Subaru Optical Spectroscopy
  61. GRB 050906: MARGE Optical Limits
  62. GRB 050906: Swift-BAT refined analysis
  63. GRB 050906: Swift XRT upper limit
  64. GRB 050906: Radio Observations
  65. GRB 050904: Keck I-band Imaging
  66. GRB050906: P60 Observations
  67. GRB 050904: more VLT NIR observations
  68. GRB 050904: photometric redshift
  69. GRB 050904: Swift/UVOT observations
  70. GRB 050904: NIR object inside the XRT error box
  71. GRB 050904: early Swift XRT analysis results
  72. GRB 050904: SOAR YJ and PROMPT Ic Observations
  73. GRB050904: Optical Observations
  74. GRB050904: P60 Observations
  75. GRB 050904: TAROT optical limits
  76. GRB 050827 : OSN 1.5m optical observations
  77. GRB 050827: P200 NIR Observations
  78. GRB050827: Swift/UVOT upper limits
  79. GRB 050827: Optical Limit
  80. GRB 050827: XRT possible afterglow detection
  81. GRB 050826 : Lulin R band observation
  82. GRB050824: Maidanak optical limits
  83. GRB 050827: Swift-BAT refined analysis
  84. Subaru Observations of GRB050724
  85. GRB 050826: Optical Candidate
  86. GRB 050826: Swift XRT preliminary analysis results
  87. GRB 050826: BAT refined analysis
  88. GRB050826: Swift/UVOT early upper limits
  89. GRB050826: Swift-BAT detection of a long burst
  90. GRB050824: MASTER final analysis of the OT observations
  91. Swift-BAT trigger 152038 is probably not a GRB
  92. GRB 050824: XRT refined analysis and possible afterglow detection
  93. GRB 050824: BAT refined analysis of a soft weak burst
  94. GRB050824: MASTER:OT decay
  95. GRB050824: MASTER observation OT
  96. GRB050805a: MASTER optical candidat
  97. XRF050509c: Radio upper limits from GMRT
  98. GRB050822: Swift/UVOT upper limits
  99. GRB 050820A BAT observations of second, larger episode of emission
  100. GRB050813: Maidanak I-band observations

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