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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"

36275 results found.

  1. GRB 050124 : Lulin R-band follow-up observation
  2. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  3. GRB 050123 : I-band follow-up observation
  4. GRB050123: optical limit 1.8h before GRB
  5. GRB050123,optical observation
  6. GRB 050123: KAIT observations
  7. GRB050123: P60 Observations
  8. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  9. CFHTLS optical transient unlikely to be a GRB
  10. Unusual optical transient (GRB ???)
  11. GRB050117a: Radio Observations
  12. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  13. GRB 050117, I-band observations
  14. GRB 050117: Optical observation
  15. GRB050117: Refined XRT position
  16. GRB050117: MASTER optical observations
  17. MASTER:GRB050117 SWIFT
  18. GRB050117: Swift-BAT detection of a long multi-peaked burst
  19. Triangulation of Short Hard GRB050112 (large error box)
  20. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  21. SGR 1806-20 and extragalactic short-duration GRBs
  22. SGR 1806-20: Temporal and Spectral behavior of radio transient
  23. SGR 1806-20, RHESSI observations of the 041227 giant flare
  24. SGR1806: Detection of a Sudden Ionospheric Disturbance
  25. GRB 041217: Optical observations
  26. GRB041219, early time observations
  27. IPN localization of giant flare from SGR1806-20
  28. GRB041219; RXTE ASM Observations
  29. NIR Observations of GRB 041219
  30. GRB041223: decay of the afterglow
  31. GRB 041224: near-infrared observations with REM
  32. GRB 041223: XRT afterglow spectrum and light curve
  33. GRB 041223 Fluence measured by Swift-BAT
  34. GRB041223: optical and NIR observations with REM
  35. GRB 041219: TAROT optical observations
  36. GRB 041218: TAROT optical observations
  37. GRB 041223: J-band observations of the afterglow
  38. GRB 041223: Detection of Optical Transient with LCO40
  39. GRB 041219c: PROMPT Observations
  40. GRB 041218: optical observations
  41. GRB 041219: Second Epoch WSRT Radio Observations
  42. GRB 041219: WSRT Radio Afterglow Detection
  43. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  44. GRB 041218: Optical observations
  45. GRB 041219 : optical follow-up observations
  46. Deep RAPTOR observations during GRB 041219
  47. GRB 041218 Optical Observations
  48. GRB 041219 Optical Observations
  49. GRB041219c: Third Burst in One Day from Swift-BAT
  50. GRB041219: Optical Afterglow Detection
  51. GRB041219: Continued NIR Observations
  52. GRB 041219 ,optical observation
  53. GRB 041219: Radio Afterglow Detection
  54. GRB 041218 : Radio Observations
  55. GRB 041218: R-band optical observations
  56. GRB041219: Confirmed NIR Afterglow
  57. GRB041218: Continued P60 Optical Observations
  58. GRB 041218: Optical Observation
  59. GRB 041219: Infrared Afterglow Candidate
  60. GRB041219, BVRcIc field calibration
  61. GRB 041219: Infrared Afterglow Candidate
  62. GRB041218, BVRcIc field calibration
  63. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  64. GRB041219: P60 Optical Observations
  65. GRB 041219 - A long GRB detected by INTEGRAL
  66. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  67. GRB 041217: PROMPT Observations
  68. GRB041218: optical observations
  69. GRB041217: optical limit 30 min after GRB
  70. GRB 041218; optical candidate
  71. GRB 041218: Optical observations
  72. GRB 041217: LCO40 Optical Observations and Possible Candidates
  73. GRB 041218 - A long GRB detected by integral
  74. GRB041217: Optical Observations
  75. GRB041217: P60 Optical Observations
  76. GRB041217: Infrared Observations
  77. GRB041217: The First GRB Located On-Board Swift
  78. GRB041211: Faulkes Telescope continued optical monitoring
  79. Optical Transient in Lynx not a GRB
  80. Optical transient (GRB?) in Lynx
  81. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  82. GRB041211: Continued P60 Observations
  83. GRB041211: RAPTOR observations
  84. GRB041211: Ashra Prototype optical observation
  85. GRB041211, Faulkes Telescope optical observation
  86. GRB041211, BVRcIc field calibration
  87. GRB 041211: Infrared Observations
  88. GRB 041211: KAIT observations
  89. GRB 041211: Optical follow-up in East Asian region
  90. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  91. GRB041211: P60 optical imaging
  92. GRB970815: Discovery of Optical Afterglow
  93. Distribution of IBAS Alerts for NON-GRB sources
  94. Triangulation of short GRB 041116 (large error box)
  95. GRB 040924: Afterglow Color
  96. GRB 041006: GETS Optical Afterglow Observation
  97. Summary of the recent bursts from SGR 1806-20
  98. GRB 041006: Optical Observations
  99. GRB041006, late-time optical photometry
  100. IBAS GRB Alert # 2034

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