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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"

23687 results found.

  1. GRB 050215b: Swift XRT Source Variability
  2. GRB 050215B: candidate afterglow
  3. GRB 050215b : Lulin follow-up observation
  4. GRB 050215b, BOOTES-2 simultaneous optical observations
  5. GRB 050215B: UKIRT K-band imaging
  6. GRB 050215b: Swift XRT Observations
  7. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  8. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  9. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  10. GRB 050209(=U11568): Duration and spectrum
  11. short/hard GRB 050202, optical observations
  12. GRB050209: REM optical observations
  13. GRB 050209 I-band observation
  14. GRB050209: P60 Optical Observations
  15. GRB050209 (=U11568): A Long GRB Detected by HETE
  16. GRB 050209: Optical observation
  17. GRB 050128: Radio observations
  18. Further analysis of the short Swift-BAT GRB 050202
  19. GRB 050202: Second epoch radio observations
  20. GRB 050129: Optical observations
  21. GRB050202: Radio Observations
  22. GRB 050202: Optical observations with LCO40
  23. GRB 050202: Short burst detected by Swift-BAT
  24. GRB 050128 Optical observation with REM
  25. GRB 050129: a weak long GRB detected with INTEGRAL
  26. SGR1806-20: Swift-BAT detection of a large normal burst
  27. GRB050128: Faulkes Telescope South observations
  28. GRB 050124: Radio Observations
  29. GRB 050128: near-infrared observations with REM
  30. GRB050126: Updated Swift XRT Position
  31. GRB 050126: Radio Observations
  32. GRB050128 Swift-BAT observations
  33. GRB 050128: Swift XRT prompt afterglow position
  34. GRB 050124: K-band afterglow observations
  35. GRB050126: MASTER optical limit for KECK OT
  36. GRB050126: Burst Parameters Measured by BAT
  37. GRB050126: MASTER optical observations
  38. GRB 050126: Prompt XRT detection and localization
  39. GRB050124: No Swift UVOT Detection of Afterglow Emission
  40. GRB 050117a: Radio Observations
  41. GRB 050124 : Lulin R-band follow-up observation
  42. GRB050124: Updated Swift XRT Position and Fluxes
  43. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  44. GRB050124: Refined BAT position, spectral and fluence information
  45. GRB050124: Swift-BAT position of a double-peaked burst
  46. GRB 050123 : I-band follow-up observation
  47. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  48. CFHTLS optical transient unlikely to be a GRB
  49. Unusual optical transient (GRB ???)
  50. GRB050117a: Refined analysis
  51. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  52. GRB050117b: Swift-BAT detection of a weak burst
  53. GRB050117: optical observation
  54. GRB 050117, I-band observations
  55. GRB050117: Refined XRT position
  56. GRB050117: MASTER optical observations
  57. MASTER:GRB050117 SWIFT
  58. GRB050117: Swift-BAT detection of a long multi-peaked burst
  59. SGR 1806-20: RXTE/PCA pulse frequency during flare
  60. SGR 1806-20: Further low frequency GMRT results
  61. SGR1806-20: Swift-BAT observations of two additional bursts
  62. Further VLA observations of SGR 1806-20
  63. Further ATCA observations of SGR 1806-20
  64. ATCA observations of SGR 1806-20
  65. Third epoch observations of SGR 1806-20 with VLA
  66. Second-epoch VLA observations of SGR 1806-20
  67. SGR1806: Detection of a Sudden Ionospheric Disturbance
  68. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  69. SGR1806 VLA Observations
  70. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  71. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  72. GRB041219, early time observations
  73. IPN localization of giant flare from SGR1806-20
  74. Giant flare from SGR 1806-20 detected by INTEGRAL
  75. GRB041228: Swift-BAT detection of a burst
  76. GRB041219; RXTE ASM Observations
  77. GRB041226: Swift-BAT detection of a burst
  78. GRB041223: decay of the afterglow
  79. GRB 041224: near-infrared observations with REM
  80. GRB 041223: XRT afterglow spectrum and light curve
  81. GRB 041223 Fluence measured by Swift-BAT
  82. GRB041224: Swift-BAT detection of a soft burst
  83. GRB041223: optical and NIR observations with REM
  84. GRB 041219: TAROT optical observations
  85. GRB 041218: TAROT optical observations
  86. GRB 041223: J-band observations of the afterglow
  87. GRB 041223: Detection of Optical Transient with LCO40
  88. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  89. GRB041223: Swift-BAT detection of a bright long burst
  90. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  91. GRB 041219 : optical follow-up observations
  92. GRB041220: Swift-BAT burst
  93. GRB041219c: Third Burst in One Day from Swift-BAT
  94. GRB041219b: A Swift-BAT burst
  95. GRB 041219: Radio Afterglow Detection
  96. GRB 041218 : Radio Observations
  97. GRB 041218: R-band optical observations
  98. Swift-BAT detection of the bright long burst GRB041219
  99. GRB041219, BVRcIc field calibration
  100. GRB041218, BVRcIc field calibration

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