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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"

18480 results found.

  1. GRB 051021, Optical Observations
  2. GRB051012: Swift-XRT analysis
  3. GRB 051022: Swift/UVOT Upper Limits
  4. GRB051022: Radio Counterpart
  5. GRB051022: IR observations
  6. GRB051021A: Swift XRT refined analysis
  7. GRB051022: Optical Observations
  8. GRB051021b: Magellan IR Imaging
  9. GRB 051021, SMARTS optical/IR observations
  10. GRB051022: Swift XRT Position
  11. GRB 051021: P200 Ks Observations
  12. GRB 051022 (=H3950): SXC Flight Localization is Valid
  13. GRB051021: Swift/UVOT Upper Limits
  14. GRB 051022: SSO40 Optical Observations
  15. GRB051022,optical observation
  16. GRB 051021,optical observation
  17. GRB 051021B: Swift detection of a burst
  18. GRB 051021: Optical observations and candidate afterglow
  19. Swift-BAT triggered on a posible CR Shower or possible GRB
  20. Afterglow candidate of GRB 051016B observed at Lulin
  21. GRB 051016A: Swift/UVOT upper limits
  22. GRB 051016B: Swift/UVOT detection
  23. GRB 051016B,optical observation
  24. GRB 051016B: Swift detection of a soft burst
  25. GRB051016 XMM-Newton observation
  26. GRB 051016: PROMPT Observations
  27. GRB051016: Swift detection of a burst
  28. GRB 051012: Swift-BAT detection of burst yesterday
  29. GRB 051006: Swift/UVOT Upper Limits
  30. GRB051008: Radio Observation
  31. GRB 051008, optical observations
  32. GRB 051008: early Swift XRT analysis
  33. GRB 051008: Swift UVOT Candidate
  34. GRB 051006: P60 Observations
  35. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  36. GRB051006: Swift detection of a burst
  37. GRB 050906, summary of radio observations
  38. GRB051001: Swift UVOT Upper Limits
  39. GRB 051001: AAT infra-red observations
  40. GRB 051001: Swift Detection of a Burst
  41. GRB 050820A: NIR photometry at the TNG
  42. GRB/SGR 050925: IR Observations
  43. GRB050925: Swift UVOT upper limits
  44. GRB050925: Faulkes Telescope North R-band limit
  45. GRB050925: Swift-BAT detection of a short burst
  46. GRB050922B: Swift UVOT early upper limits.
  47. GRB 050922C: optical obserations
  48. GRB 050922C: NOT optical observations
  49. GRB 050922C: Swift detection of a bright burst
  50. GRB 050922B: ROTSE-III Optical Limits
  51. GRB 050922B,optical observation
  52. GRB050922B: Swift-BAT detection of a weak long burst
  53. GRB050820B: analysis of the XMM-Newton observation
  54. GRB050916: Swift/UVOT Upper Limits
  55. Swift-BAT trigger 155764 is not a GRB
  56. Swift-BAT trigger 155764 is probably not a GRB
  57. Swift trigger 155764: bad XRT centroid
  58. Swift-BAT trigger 155535 is definitely not a GRB
  59. GRB 050915B: Swift/UVOT Upper Limits
  60. GRB 050915a: IR Transient
  61. GRB 050915b, SMARTS optical/IR observations
  62. GRB050915B: Swift-BAT detection of a long bright burst
  63. GRB050915: Swift/UVOT upper limits
  64. GRB 050915: IR Observations
  65. GRB 050915: Swift detection of a GRB
  66. Swift-BAT trigger 155072 is probably not a GRB
  67. GRB 050911: z~0.16 cluster in the field
  68. GRB050911: Swift-BAT detection of a long burst
  69. GRB 050910a: TAROT early optical limits
  70. GRB 050906: Possible X-ray Counterpart
  71. GRB050908: Swift/UVOT Early upper limits
  72. GRB050908 : Swift-XRT refined analysis
  73. GRB 050908: Optical observations
  74. GRB 050908: Swift detection of a burst
  75. GRB 050906: Optical observations at the Very Large Telescope
  76. GRB 050904: Subaru Optical Spectroscopy
  77. GRB 050906: Swift XRT upper limit
  78. GRB 050904: Keck I-band Imaging
  79. GRB050906: P60 Observations
  80. GRB 050904: photometric redshift
  81. GRB 050904: Swift/UVOT observations
  82. GRB 050904: NIR object inside the XRT error box
  83. GRB 050904: early Swift XRT analysis results
  84. GRB050904: Optical Observations
  85. GRB050904: P60 Observations
  86. GRB 050904: TAROT optical limits
  87. GRB 050827: P200 NIR Observations
  88. GRB050827: Swift/UVOT upper limits
  89. GRB050824: Maidanak optical limits
  90. GRB 050827: Swift-BAT refined analysis
  91. Subaru Observations of GRB050724
  92. GRB050826: Swift/UVOT early upper limits
  93. GRB050826: Swift-BAT detection of a long 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. GRB050813: Maidanak I-band observations
  100. GRB050525, GRB050607, GRB050802 BVRcIc field photometry

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