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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"

45770 results found.

  1. GRB 051021,optical observation
  2. GRB051021B: Swift XRT Position
  3. GRB 051021: SOAR NIR Observations
  4. GRB 051021B: Swift detection of a burst
  5. GRB051021: Swift XRT analysis
  6. GRB051021 (=H3947): Refined Analysis
  7. GRB 051021 : optical afterglow observation at Lulin
  8. GRB 051021: Optical observations
  9. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  10. GRB 051021: Optical observations and candidate afterglow
  11. Swift-BAT trigger 160640 is not a real GRB
  12. GRB051021: A GRB Localized by HETE
  13. Swift-BAT trigger 160619 is not a GRB
  14. Swift-BAT triggered on a posible CR Shower or possible GRB
  15. GRB 050502b: Optical limit
  16. GRB 051016b: Optical limit
  17. Afterglow candidate of GRB 051016B observed at Lulin
  18. GRB 051016b: Gemini Near IR Observations
  19. GRB 051016A: Swift/UVOT upper limits
  20. GRB 051016B: refined analysis of the Swift/XRT data
  21. GRB 051016B: Swift/UVOT detection
  22. GRB 051016B,optical observation
  23. GRB 051016B : Optical follow-up at Lulin
  24. GRB 051016B: Refined analysis of the Swift-BAT burst
  25. GRB 051016B: Swift detection of a soft burst
  26. GRB 051016: Swift-BAT refined analysis
  27. GRB051016 XMM-Newton observation
  28. GRB051016: Swift XRT refined analysis.
  29. GRB051016: Planned XMM-Newton observation
  30. GRB 051016: LCO optical and near-IR imaging
  31. GRB 051016: PROMPT Observations
  32. GRB051016: Swift detection of a burst
  33. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  34. GRB051006: optical observations
  35. GRB 051012: Swift-BAT detection of burst yesterday
  36. Swift trigger 159578 is not a burst
  37. Swift-BAT Trigger 159578 is a possible burst
  38. GRB050805A: Rc optical observations
  39. GRB 051006: Swift/UVOT Upper Limits
  40. IBAS Alert 2675 : not a GRB
  41. GRB051008: optical candidate
  42. GRB 051008: - a high redshift high-luminosity burst?
  43. GRB 051008 - a low redshift low-luminosity burst?
  44. IBAS Alert 2673: not a real GRB
  45. GRB051011: bright nebulae near error box
  46. GRB051008: optical observation
  47. GRB051008: Swift XRT refined analysis
  48. GRB051008 - Swift UVOT upper limits
  49. Konus-Wind observation of GRB 051008
  50. GRB051008: Final refined analysis of the Swift-BAT burst
  51. GRB 051008: R-band upper limit
  52. GRB051008: Refined analysis of the Swift-BAT burst
  53. GRB051008: Radio Observation
  54. GRB 051008: Swift XRT position
  55. GRB 051008, optical observations
  56. GRB 051008: early Swift XRT analysis
  57. GRB 051008: Swift UVOT Candidate
  58. GRB051008: Swift-BAT detection of a bright burst
  59. GRB 051006: P60 Observations
  60. grb test
  61. GRB 051006: XRT refined analysis
  62. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  63. GRB 051006: optical observations at Sierra Nevada
  64. GRB051006: Refined analysis of the Swift-BAT burst
  65. GRB 051006: XRT position
  66. GRB051006: Swift detection of a burst
  67. GRB 050906, summary of radio observations
  68. Swift-BAT triggers 158261 and 158262 Retraction
  69. GRB051001: Swift UVOT Upper Limits
  70. GRB 050925: Second Epoch WSRT Radio Observations
  71. GRB 051001: Swift XRT refined analysis
  72. GRB 051001, optical observations at Mt. John
  73. GRB 051001: I-band limit
  74. GRB 051001: AAT infra-red observations
  75. GRB 051001: Swift-BAT refined analysis
  76. GRB 051001: Swift Detection of a Burst
  77. GRB 051001: ROTSE-III Optical Limits
  78. GRB050908: optical observations
  79. GRB050922C: optical observation
  80. GRB050922B: optical limit
  81. GRB 050922C: further VLT observations
  82. GRB 050820A: NIR photometry at the TNG
  83. GRB050922C: UVES/VLT high resolution spectroscopy
  84. GRB050925: Swift/XRT limits
  85. GRB/SGR 050925: IR Observations
  86. GRB050922C - Swift UVOT preliminary analysis
  87. GRB 050922C: break in the lightcurve
  88. GRB 050925: WSRT Radio Observations
  89. GRB050925: Swift UVOT upper limits
  90. Refined analysis of the Swift-BAT soft short burst
  91. GRB 050925 : I-band observation at Xinglong observatory
  92. GRB050925: Faulkes Telescope North R-band limit
  93. GRB050925: Swift-BAT detection of a short burst
  94. GRB 050922B: Correction to BAT refined analysis, longer burst
  95. GRB050922C: TNG spectroscopic observations
  96. GRB050922B: refined XRT analysis
  97. Konus-Wind observation of GRB 050922C
  98. GRB 050922C: Refined redshift
  99. GRB050922B: Swift UVOT early upper limits.
  100. GRB OT observation

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