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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"

15247 results found.

  1. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  2. GRB 051021, SMARTS optical/IR observations
  3. GRB 051021: P200 Ks Observations
  4. GRB 051021: MDM Upper Limit
  5. GRB 051022 (=H3950): SXC Flight Localization is Valid
  6. GRB 051021,optical observation
  7. GRB051021B: Swift XRT Position
  8. GRB 051021B: Swift detection of a burst
  9. GRB051021: Swift XRT analysis
  10. GRB 051021 : optical afterglow observation at Lulin
  11. GRB 051021: Optical observations
  12. GRB051021: A GRB Localized by HETE
  13. Afterglow candidate of GRB 051016B observed at Lulin
  14. GRB 051016b: Gemini Near IR Observations
  15. GRB 051016B: refined analysis of the Swift/XRT data
  16. GRB 051016B: Swift/UVOT detection
  17. GRB051016: Swift XRT refined analysis.
  18. GRB 051016: PROMPT Observations
  19. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  20. Swift-BAT Trigger 159578 is a possible burst
  21. GRB051008: optical candidate
  22. GRB 051008: - a high redshift high-luminosity burst?
  23. GRB 051008 - a low redshift low-luminosity burst?
  24. GRB051008: Swift XRT refined analysis
  25. Konus-Wind observation of GRB 051008
  26. GRB 051008: R-band upper limit
  27. GRB 051008: Swift XRT position
  28. GRB 051008, optical observations
  29. GRB 051006: XRT refined analysis
  30. GRB 051006: XRT position
  31. GRB051006: Swift detection of a burst
  32. GRB 050906, summary of radio observations
  33. GRB 050925: Second Epoch WSRT Radio Observations
  34. GRB 051001: Swift XRT refined analysis
  35. GRB 051001, optical observations at Mt. John
  36. GRB 051001: Swift-BAT refined analysis
  37. GRB 050922C: further VLT observations
  38. GRB 050820A: NIR photometry at the TNG
  39. GRB050922C: UVES/VLT high resolution spectroscopy
  40. GRB/SGR 050925: IR Observations
  41. GRB050925: Swift UVOT upper limits
  42. GRB050925: Faulkes Telescope North R-band limit
  43. GRB 050922B: Correction to BAT refined analysis, longer burst
  44. GRB050922B: refined XRT analysis
  45. Konus-Wind observation of GRB 050922C
  46. GRB OT observation
  47. GRB050922C: observation at MonteBoo
  48. GRB050922C: Optical Observations
  49. GRB 050922C: Swift XRT refined analysis
  50. HETE Fregate observations of GRB 050922C
  51. GRB 050922C: Swift detection of a bright burst
  52. GRB 050922C: ROTSE-IIId Refined Analysis
  53. GRB050922B: Swift-BAT detection of a weak long burst
  54. GRB050820B: analysis of the XMM-Newton observation
  55. GRB050916: Swift/UVOT Upper Limits
  56. GRB 050916: Swift-BAT refined analysis
  57. GRB 050915a: Radio Observations
  58. Swift-BAT trigger 155535 is definitely not a GRB
  59. GRB 050916: XRT position
  60. GRB 050915b, SMARTS optical/IR observations of the XRT position
  61. GRB050916: Swift-BAT detection of a long weak burst
  62. GRB 050915a: IR Transient
  63. GRB 050915B: XRT position
  64. GRB 050915: Swift XRT refined analysis
  65. GRB 050915: Swift-BAT refined analysis
  66. GRB050915, optical observations
  67. GRB050915: XRT position
  68. Swift-BAT trigger 155072 ground analysis
  69. GRB 050908: DEIMOS spectrum and further analysis
  70. GRB050911: Swift-XRT position
  71. GRB050908: detection of Swift/UVOT optical counterpart
  72. RBO GRB 050908 observations
  73. WIRO observations in I of GRB 050908
  74. GRB050908 : Swift-XRT refined analysis
  75. GRB 050908: Swift-BAT refined analysis
  76. GRB 050908: Optical observations
  77. Gemini Spectroscopy of GRB 050908
  78. GRB 050908 : Swift XRT position
  79. GRB 050908: KAIT observations
  80. GRB 050904 BAT refined analysis of complete data set
  81. GRB 050904: Subaru Optical Spectroscopy
  82. GRB 050906: Swift-BAT refined analysis
  83. GRB 050906: Swift XRT upper limit
  84. GRB 050904: Keck I-band Imaging
  85. GRB 050904: BOOTES early R-band observation
  86. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  87. GRB 050906: Swift/BAT Detection of a possible burst
  88. GRB 050904: Swift/UVOT observations
  89. GRB 050904: BAT refined analysis of partial data set
  90. GRB 050904: TAROT optical measurements
  91. GRB050904: Optical Observations
  92. GRB 050904: Environmental Constraints
  93. GRB 050904: Possible High-Redshift GRB
  94. GRB 050904: SOAR/PROMPT Observations
  95. GRB050904: Swift-BAT detection of a probable burst
  96. Retraction of Swift-BAT trigger #153355
  97. Swift Trigger #152652 is not a GRB
  98. GRB 050827: Optical Limit
  99. Subaru Observations of GRB050724
  100. GRB050824, HETE-2 Observation

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