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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"

39317 results found.

  1. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  2. GRB 050124, SMARTS optical/IR observations
  3. GRB 050117a: Radio Observations
  4. GRB 050124 I-band observation
  5. GRB 050124: NIR Candidates from Keck/NIRC
  6. GRB050124,optical observation
  7. GRB 050124 : Lulin R-band follow-up observation
  8. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  9. GRB050124: Swift-BAT position of a double-peaked burst
  10. GRB 050123 : I-band follow-up observation
  11. GRB050123: optical limit 1.8h before GRB
  12. GRB050123,optical observation
  13. GRB 050123: KAIT observations
  14. GRB050123: P60 Observations
  15. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  16. CFHTLS optical transient unlikely to be a GRB
  17. Unusual optical transient (GRB ???)
  18. GRB050117a: Radio Observations
  19. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  20. GRB050117b: Swift-BAT detection of a weak burst
  21. GRB 050117, I-band observations
  22. GRB 050117: Optical observation
  23. GRB050117: Refined XRT position
  24. GRB050117: MASTER optical observations
  25. MASTER:GRB050117 SWIFT
  26. GRB050117: Swift-BAT detection of a long multi-peaked burst
  27. GRB050117: Swift XRT Position
  28. Triangulation of Short Hard GRB050112 (large error box)
  29. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  30. SGR 1806-20 and extragalactic short-duration GRBs
  31. SGR 1806-20: Temporal and Spectral behavior of radio transient
  32. SGR 1806-20, RHESSI observations of the 041227 giant flare
  33. SGR1806: Detection of a Sudden Ionospheric Disturbance
  34. GRB 041217: Optical observations
  35. GRB041219, early time observations
  36. IPN localization of giant flare from SGR1806-20
  37. GRB041228: ROTSE-III Optical Observations
  38. GRB041228: Swift-BAT detection of a burst
  39. GRB041219; RXTE ASM Observations
  40. NIR Observations of GRB 041219
  41. GRB041226: ROTSE-III Optical Observations
  42. GRB041226: Swift-BAT detection of a burst
  43. GRB041223: decay of the afterglow
  44. GRB041224: ROTSE-III Optical Observations
  45. GRB 041224: near-infrared observations with REM
  46. GRB 041223: XRT afterglow spectrum and light curve
  47. GRB 041223 Fluence measured by Swift-BAT
  48. GRB041224: Swift-BAT detection of a soft burst
  49. GRB041223: optical and NIR observations with REM
  50. Swift-BAT Time History of GRB041219
  51. GRB 041219: TAROT optical observations
  52. GRB 041218: TAROT optical observations
  53. GRB 041223: J-band observations of the afterglow
  54. GRB 041223: Detection of Optical Transient with LCO40
  55. GRB 041219c: PROMPT Observations
  56. GRB041223: ROTSE-III Optical Observations
  57. GRB041223: Swift-BAT detection of a bright long burst
  58. GRB 041218: optical observations
  59. GRB 041219: Second Epoch WSRT Radio Observations
  60. GRB 041219: WSRT Radio Afterglow Detection
  61. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  62. GRB 041218: Optical observations
  63. GRB 041219 : optical follow-up observations
  64. GRB041220: Swift-BAT burst
  65. Deep RAPTOR observations during GRB 041219
  66. GRB 041218 Optical Observations
  67. GRB 041219 Optical Observations
  68. GRB041219c: Third Burst in One Day from Swift-BAT
  69. GRB041219: Optical Afterglow Detection
  70. GRB041219: Continued NIR Observations
  71. GRB041219b: A Swift-BAT burst
  72. GRB 041219 ,optical observation
  73. GRB 041219: Radio Afterglow Detection
  74. GRB 041218 : Radio Observations
  75. GRB 041218: R-band optical observations
  76. GRB041219: Confirmed NIR Afterglow
  77. GRB041218: Continued P60 Optical Observations
  78. Swift-BAT detection of the bright long burst GRB041219
  79. GRB 041218: Optical Observation
  80. GRB 041219: Infrared Afterglow Candidate
  81. GRB041219, BVRcIc field calibration
  82. GRB 041219: Infrared Afterglow Candidate
  83. GRB041218, BVRcIc field calibration
  84. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  85. GRB041219: P60 Optical Observations
  86. GRB 041219 - A long GRB detected by INTEGRAL
  87. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  88. GRB 041217: PROMPT Observations
  89. GRB041218: optical observations
  90. GRB041217: optical limit 30 min after GRB
  91. GRB 041218; optical candidate
  92. GRB 041218: Optical observations
  93. GRB 041217: LCO40 Optical Observations and Possible Candidates
  94. GRB 041218 - A long GRB detected by integral
  95. GRB041217: Optical Observations
  96. GRB041217: P60 Optical Observations
  97. GRB041217: Infrared Observations
  98. GRB041217: The First GRB Located On-Board Swift
  99. GRB041211: Faulkes Telescope continued optical monitoring
  100. Optical Transient in Lynx not a GRB

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