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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"

41908 results found.

  1. GRB050126: Burst Parameters Measured by BAT
  2. GRB050126: MASTER optical observations
  3. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  4. GRB 050126: Prompt XRT detection and localization
  5. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  6. GRB050124: No Swift UVOT Detection of Afterglow Emission
  7. GRB 050124, SMARTS optical/IR observations
  8. GRB 050117a: Radio Observations
  9. GRB 050124 I-band observation
  10. GRB 050124: NIR Candidates from Keck/NIRC
  11. GRB050124,optical observation
  12. GRB 050124 : Lulin R-band follow-up observation
  13. GRB050124: Updated Swift XRT Position and Fluxes
  14. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  15. GRB050124: Refined BAT position, spectral and fluence information
  16. GRB 050123 : I-band follow-up observation
  17. GRB050123: optical limit 1.8h before GRB
  18. GRB 050123: KAIT observations
  19. GRB050123: P60 Observations
  20. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  21. CFHTLS optical transient unlikely to be a GRB
  22. Unusual optical transient (GRB ???)
  23. GRB050117a: Radio Observations
  24. GRB050117a: Refined analysis
  25. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  26. GRB050117: Palomar WIRC Ks-band observations
  27. GRB050117: optical observation
  28. GRB 050117, I-band observations
  29. GRB 050117: Optical observation
  30. GRB050117: Refined XRT position
  31. GRB050117: MASTER optical observations
  32. MASTER:GRB050117 SWIFT
  33. GRB050117: Swift-BAT detection of a long multi-peaked burst
  34. GRB050117: Swift XRT Position
  35. SGR 1806-20: RXTE/PCA pulse frequency during flare
  36. Triangulation of Short Hard GRB050112 (large error box)
  37. SGR 1806-20: Further VLA Observations
  38. SGR 1806-20: Further low frequency GMRT results
  39. SGR 1806-20: Further VLA Observations
  40. SGR1806-20: Swift-BAT observations of two additional bursts
  41. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  42. Further VLA observations of SGR 1806-20
  43. SGR 1806-20 and extragalactic short-duration GRBs
  44. Further ATCA observations of SGR 1806-20
  45. Fourth Epoch VLA observations of SGR 1806-20
  46. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  47. SGR 1806-20: Temporal and Spectral behavior of radio transient
  48. ATCA observations of SGR 1806-20
  49. SGR 1806-20, RHESSI observations of the 041227 giant flare
  50. Third epoch observations of SGR 1806-20 with VLA
  51. Second Epoch VLA observations of SGR 1806-20
  52. Second-epoch VLA observations of SGR 1806-20
  53. SGR1806: Detection of a Sudden Ionospheric Disturbance
  54. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  55. VLA observations of SGR 1806-20
  56. SGR1806 VLA Observations
  57. VLA observations of SGR 1806-20
  58. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  59. GRB 041217: Optical observations
  60. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  61. GRB041219, early time observations
  62. Detection of the SGR 1806-20 giant outburst back-scattered by the
  63. The giant outburst from SGR 1806-20
  64. IPN localization of giant flare from SGR1806-20
  65. Giant flare from SGR 1806-20 detected by INTEGRAL
  66. GRB041228: ROTSE-III Optical Observations
  67. GRB041228: Swift-BAT detection of a burst
  68. GRB041219; RXTE ASM Observations
  69. NIR Observations of GRB 041219
  70. GRB041226: ROTSE-III Optical Observations
  71. GRB041226: Swift-BAT detection of a burst
  72. GRB041223: decay of the afterglow
  73. GRB041224: ROTSE-III Optical Observations
  74. GRB 041224: near-infrared observations with REM
  75. GRB 041223: XRT afterglow spectrum and light curve
  76. GRB 041223 Fluence measured by Swift-BAT
  77. GRB041224: Swift-BAT detection of a soft burst
  78. GRB041223: optical and NIR observations with REM
  79. Swift-BAT Time History of GRB041219
  80. GRB 041219: TAROT optical observations
  81. GRB 041218: TAROT optical observations
  82. GRB 041223: J-band observations of the afterglow
  83. GRB 041223: Detection of Optical Transient with LCO40
  84. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  85. GRB 041219c: PROMPT Observations
  86. GRB041223: ROTSE-III Optical Observations
  87. GRB041223: Swift-BAT detection of a bright long burst
  88. GRB 041218: optical observations
  89. Very high activity of SGR 1806-20
  90. GRB 041219: Second Epoch WSRT Radio Observations
  91. GRB 041219: WSRT Radio Afterglow Detection
  92. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  93. GRB 041218: Optical observations
  94. GRB 041219 : optical follow-up observations
  95. GRB041220: Swift-BAT burst
  96. Deep RAPTOR observations during GRB 041219
  97. GRB 041218 Optical Observations
  98. GRB 041219 Optical Observations
  99. GRB041219c: Third Burst in One Day from Swift-BAT
  100. GRB041219: Optical Afterglow Detection

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