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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"

36352 results found.

  1. GRB 051221: Discovery of fading optical afterglow
  2. GRB 051221: Swift XRT refined analysis
  3. GRB 051221: Swift/UVOT upper limits
  4. GRB 051221: Possible nearby cluster
  5. GRB 051221: No variability in Gemini data
  6. GRB 051221: Correction to GCN #4368
  7. GRB 051221: Gemini observations
  8. GRB 051221: Improved astrometry of the IR counterpart
  9. GRB051221: K-band source
  10. GRB 051221: XRT position
  11. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  12. GRB 051221: IR Observations at GRB+1hr
  13. GRB 051221: Swift detection of a bright short burst
  14. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  15. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  16. GRB 051211B: optical afterglow
  17. Swift detection of an RS CVn flare star
  18. GRB051211A: possible optical candidate
  19. Swift Trigger 172767 is not a GRB
  20. GRB 051215: near-infrared observations
  21. GRB051215 - SDSS pre-burst observations
  22. GRB 051215: Swift detection of a possible burst
  23. GRB 051215: A short GRB in a cluster?
  24. GRB051105: optical observations
  25. GRB 051213: Swift-BAT refined analysis
  26. GRB 051211B, optical observation
  27. GRB 051213: Swift-BAT detection of a burst
  28. GRB 051211a: RTT150 optical observations
  29. GRB051211B, RBO optical observations
  30. GRB 051211A: Swift/UVOT upper limits
  31. GRB 051211B: Swift/UVOT upper limits - correction
  32. GRB 051211B: Swift/UVOT upper limits
  33. GRB 051211A,optical observation
  34. GRB 051211B: Swift XRT confirmation of the afterglow
  35. GRB051211B: Liverpool Telescope observation
  36. GRB 051211b: RTT150 optical observations
  37. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  38. GRB 051211B: Swift XRT Observations
  39. GRB 051210: Swift/UVOT upper limits
  40. GRB 051210: Magellan Imaging
  41. GRB 051211: TAROT optical limits
  42. GRB 051211B: a possible optical detection by TAROT
  43. GRB 051211B: a long GRB detected by INTEGRAL
  44. GRB 051211: Swift XRT upper limit
  45. GRB 051211:IAC80 optical observations
  46. HETE SXC localization of GRB 051211 (=H3979)
  47. GRB 051210: Optical imaging from Las Campanas
  48. GRB 051210: SALT detection limit
  49. GRB 051210: BAT further refined analysis of the short burst
  50. GRB 051210: Swift XRT refined analysis
  51. GRB 051210: FRAM early limit
  52. GRB 051210: Swift-BAT refined analysis of a short burst
  53. GRB 051210: A short GRB in a cluster?
  54. GRB 051210: Swift detection of a burst
  55. IPN observations of SGR1806-20
  56. An extraordinary long burst on December 3 from SGR1806-20
  57. IBAS Alert 2706 : not a real GRB
  58. GRB051117B: optical observation
  59. GRB051111: optical observaion
  60. Swift-BAT trigger 165579 is not a GRB
  61. GRB 051127: Swift-BAT detection of a possible burst
  62. GRB051117b: No Swift/UVOT Detection
  63. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  64. GRB 051117A: Swift/UVOT Detection of an Afterglow
  65. GRB051111: Suzaku WAM observation of the prompt emission
  66. GRB051008: Suzaku WAM observation of the prompt emission
  67. GRB 051109B: GAO 150cm telescope Optical limit
  68. GRB 051109A : GAO 150cm telescope Rc-band detection
  69. GRB 051021 Optical Observations
  70. GRB 051117B: MARGE Optical Limits
  71. GRB 051117A and B: Radio Observations
  72. GRB 051117B: R and I observations of possible host galaxy
  73. GRB 051117b: NIR observations
  74. GRB 051117A: Refined analysis of the Swift-BAT burst
  75. GRB 051117B: Refined analysis of the Swift-BAT burst
  76. GRB 051117B,optical observation
  77. GRB 051117B: Lulin R and I band observation
  78. GRB 051117B: Optical observations
  79. GRB 051117B: ROTSE-III Optical Limits
  80. GRB 051117B: Swift detection of a burst
  81. GRB 051117: Swift detection of a bright burst
  82. GRB 051028 Optical Observations
  83. GRB 051109B : Nainital upper limits
  84. GRB 051114: Radio Observations
  85. GRB 051114: Swift-BAT refined analysis
  86. GRB051109A optical observations
  87. GRB 051114: Swift-BAT detection of a short burst
  88. GRB 051111: Further spectroscopic analysis
  89. GRB 051111: Radio afterglow
  90. GRB 051113: Swift-BAT refined analysis
  91. GRB 051113: Swift-BAT detection of a burst
  92. GRB 051111: AEOS optical observations
  93. GRB051103: Radio Observations
  94. GRB 051109A Milagro GeV/TeV Observations
  95. GRB/SGR 050925: XMM-Newton ToO observation
  96. GRB051111: Swift/UVOT Observations
  97. GRB 051111A : R-band temporal decay index based on Lulin
  98. GRB 051111: Swift-BAT refined analysis
  99. GRB 051109A Optical Observations
  100. GRB 051111A : Lulin BVRI multi band afterglow observation

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