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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"

32756 results found.

  1. GRB060105: Suzaku-XIS and -HXD observation plan
  2. GRB060105, optical observation
  3. GRB060105: Swift detection of a bright long burst
  4. Swift-BAT trigger 175653 is not an astrophysical source
  5. GRB 060102: MDM Observation
  6. Swift-BAT trigger 175653 is probably not a GRB
  7. GRB 060102: Swift-BAT refined analysis
  8. Time Correction to GRB 060102
  9. GRB 060102: Swift-BAT detection of a burst
  10. GRB051211B: optical observations
  11. GRB051227: SARA Observations
  12. GRB 051221B: Optical Observations with Kuiper 1.54m
  13. GRB 051227: Likely host galaxy underlying afterglow position
  14. GRB 051227: optical observation
  15. GRB051221B: Radio observations
  16. GRB 051221A: VLA Radio Observations
  17. GRB051227: Radio Observations
  18. GRB 051227: Confirmed fading from Gemini observations
  19. GRB051227: further analysis of VLT images
  20. GRB 051227: optical afterglow
  21. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  22. GRB 051227: Gemini observations
  23. GRB 051227: Keck Spectroscopy
  24. GRB 051227: Magellan r'-band Imaging/Astrometry
  25. GRB 051227: refined analysis of VLT images
  26. GRB 051227: P60 Observations
  27. GRB 051227: MDM Observation
  28. GRB 051227: R-band object in the XRT error circle
  29. GRB 051227: Joint Swift-HETE Spectral Analysis
  30. GRB 051227: XRT refined analysis
  31. GRB 051227: Refined analysis of the Swift-BAT burst
  32. GRB 051227, optical observation
  33. GRB051117B: optical observation
  34. Konus-Wind observation of GRB 051221A
  35. GRB 051221A: MDM Optical Observations
  36. GRB 051221A: Detection at 251nm with Swift UVOT
  37. GRB 051221A: Chandra Afterglow Position
  38. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  39. GRB 051221B: ROTSE-III Optical Limits
  40. GRB 051221B: TAROT optical limits
  41. GRB 051221A: WSRT Radio Observations
  42. GRB 051221: Redshift from Gemini
  43. GRB 051221: Continued fading of optical afterglow
  44. GRB 051221B: Refined analysis of the Swift-BAT burst
  45. Possible GRB 051221B: MDM Optical Detection
  46. GRB 051221A: RAPTOR Fading Counterpart Constraint
  47. Possible GRB 051221B: Swift XRT position
  48. GRB 051221: Discovery of fading optical afterglow
  49. GRB 051221: Swift XRT refined analysis
  50. GRB 051221: Swift/UVOT upper limits
  51. GRB 051221: Possible nearby cluster
  52. GRB 051221: Correction to GCN #4368
  53. GRB 051221: Gemini observations
  54. GRB 051221: Improved astrometry of the IR counterpart
  55. GRB051221: K-band source
  56. GRB 051221: XRT position
  57. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  58. GRB 051221: IR Observations at GRB+1hr
  59. Refined analysis of the SWIFT J1626.6-5156
  60. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  61. GRB051211A (=H3979): Refined Analysis
  62. GRB 051211B: optical afterglow
  63. GRB051211A: possible optical candidate
  64. Swift Trigger 172767 is not a GRB
  65. GRB 051215: near-infrared observations
  66. GRB051215 - SDSS pre-burst observations
  67. GRB 051215: A short GRB in a cluster?
  68. GRB051211B: Probable radio afterglow
  69. GRB051105: optical observations
  70. GRB 051213: Swift-BAT refined analysis
  71. GRB051211B: XRT refined analysis
  72. GRB051211B, RBO optical observations
  73. GRB 051211A: Swift/UVOT upper limits
  74. GRB 051211B: Swift/UVOT upper limits - correction
  75. GRB 051211B: Swift/UVOT upper limits
  76. GRB 051211A,optical observation
  77. GRB 051211B: Swift XRT confirmation of the afterglow
  78. GRB051211B: Liverpool Telescope observation
  79. GRB 051211b: RTT150 optical observations
  80. GRB051211b: P60 Observations
  81. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  82. GRB 051211B: Swift XRT Observations
  83. GRB 051210: Swift/UVOT upper limits
  84. GRB 051210: Magellan Imaging
  85. GRB 051211: TAROT optical limits
  86. GRB 051211B: a possible optical detection by TAROT
  87. GRB 051211: Swift XRT upper limit
  88. HETE SXC localization of GRB 051211 (=H3979)
  89. GRB 051210: SALT detection limit
  90. GRB 051210: Swift XRT refined analysis
  91. GRB 051210: FRAM early limit
  92. GRB 051210: Swift-BAT refined analysis of a short burst
  93. GRB051210: Swift UVOT Observation
  94. GRB 051210: A short GRB in a cluster?
  95. IPN observations of SGR1806-20
  96. Swift XRT positions
  97. An extraordinary long burst on December 3 from SGR1806-20
  98. GRB051117B: optical observation
  99. GRB051111: optical observaion
  100. Swift-BAT trigger 165579 is not a GRB

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