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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36351 results found.

  1. HETE Fregate observations of GRB 050922C
  2. GRB 050922C: Swift-BAT refined analysis
  3. GRB 050922B: Swift-BAT refined analysis
  4. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  5. GRB 050922C: optical obserations
  6. GRB 050922C: NOT optical observations
  7. GRB 050922A: Analysis of Swift/XRT TOO observation
  8. GRB 050922C: Swift detection of a bright burst
  9. GRB 050922C: ROTSE-IIId Refined Analysis
  10. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  11. GRB 050922B: ROTSE-III Optical Limits
  12. GRB 050922B,optical observation
  13. GRB050922B: Swift-BAT detection of a weak long burst
  14. Possible GRB 050922 detected by INTEGRAL
  15. GRB050820B: analysis of the XMM-Newton observation
  16. GRB050916: Swift/UVOT Upper Limits
  17. GRB 050916: Swift-BAT refined analysis
  18. GRB 050918 - A long GRB detected by INTEGRAL
  19. GRB 050915a: Radio Observations
  20. Swift-BAT trigger 155764 is not a GRB
  21. Swift-BAT trigger 155764 is probably not a GRB
  22. Swift-BAT trigger 155535 is definitely not a GRB
  23. GRB 050916: XRT position
  24. GRB 050915b, SMARTS optical/IR observations of the XRT position
  25. GRB 050915B: Swift-BAT refined analysis
  26. GRB 050915B: Swift/UVOT Upper Limits
  27. GRB 050915a: IR Transient
  28. GRB 050915B: XRT position
  29. GRB 050915b, SMARTS optical/IR observations
  30. GRB 050915: KAIT optical limit
  31. GRB 050915: IR Observations
  32. GRB 050915: Swift XRT refined analysis
  33. GRB 050915: Swift-BAT refined analysis
  34. GRB050915: P60 Optical Observations
  35. GRB 050915: ROTSE-III optical limits
  36. GRB 050915: Swift detection of a GRB
  37. GRB050911: Upper limit on X-ray afterglow
  38. Swift-BAT trigger 155072 ground analysis
  39. Swift-BAT trigger 155072 is probably not a GRB
  40. GRB 050911: LCO limits on a variable source
  41. GRB 050908: DEIMOS spectrum and further analysis
  42. Swift is in normal operation
  43. GRB 050911, optical content of Swift/XRT error box
  44. GRB 050911: LCO observations
  45. GRB 050911, optical observations
  46. GRB 050911: Swift-BAT refined analysis
  47. Later Swift-BAT triggers 154632 and 154633 RETRACTION
  48. GRB 050911: z~0.16 cluster in the field
  49. GRB 050910a: TAROT early optical limits
  50. RBO GRB 050908 observations
  51. WIRO observations in I of GRB 050908
  52. GRB 050906: Possible X-ray Counterpart
  53. GRB 050906: RTT150 optical observations
  54. GRB050908: VLT R-band decay index.
  55. GRB 050908: Swift-BAT refined analysis
  56. GRB 050908: Optical observations
  57. Gemini Spectroscopy of GRB 050908
  58. GRB 050908: spectroscopic redshift
  59. GRB 050908: Prompt PROMPT Observations
  60. GRB 050908 : Swift XRT position
  61. GRB 050908: KAIT observations
  62. GRB 050908: P60 Confirmation of Optical Afterglow
  63. GRB 050908: Optical Observations
  64. GRB 050908: Swift detection of a burst
  65. Swift trigger 154073 is not a GRB
  66. GRB 050906: Optical observations at the Very Large Telescope
  67. GRB050904: CrAO optical observations
  68. GRB 050904 BAT refined analysis of complete data set
  69. GRB 050904: Subaru Optical Spectroscopy
  70. GRB 050906: MARGE Optical Limits
  71. GRB 050906: Swift-BAT refined analysis
  72. GRB 050906: Swift XRT upper limit
  73. GRB 050906: Radio Observations
  74. GRB 050904: Keck I-band Imaging
  75. GRB 050904: more VLT NIR observations
  76. GRB 050904: BOOTES early R-band observation
  77. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  78. GRB 050906: Bright galaxy in BAT error box
  79. GRB 050906: Swift/BAT Detection of a possible burst
  80. GRB 050904: More SOAR
  81. GRB 050904: photometric redshift
  82. GRB 050904: Swift/UVOT observations
  83. GRB 050904: Afterglow Astrometry
  84. GRB 050904: NIR object inside the XRT error box
  85. GRB 050904: early Swift XRT analysis results
  86. GRB 050904: SOAR YJ and PROMPT Ic Observations
  87. GRB 050904: BAT refined analysis of partial data set
  88. GRB 050904: TAROT optical measurements
  89. GRB050904: Optical Observations
  90. GRB 050904: Environmental Constraints
  91. GRB 050904: Possible High-Redshift GRB
  92. GRB 050904: SOAR/PROMPT Observations
  93. GRB 050904: TAROT optical limits
  94. Swift-BAT triggers 153461-153465 are not GRBs
  95. GRB 050824: MDM Observations
  96. GRB 050827: Swift XRT preliminary analysis results
  97. IBAS Alerts 2641 and 2642: not a real GRB
  98. Swift Trigger #152652 is not a GRB
  99. GRB 050827 : OSN 1.5m optical observations
  100. GRB 050827: P200 NIR Observations

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