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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"

42261 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. GRB050124: Updated Swift XRT Position and Fluxes
  13. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  14. GRB050124: Refined BAT position, spectral and fluence information
  15. GRB050124: Swift-BAT position of a double-peaked burst
  16. GRB 050123 : I-band follow-up observation
  17. GRB050123: optical limit 1.8h before GRB
  18. GRB050123,optical observation
  19. GRB 050123: KAIT observations
  20. GRB050123: P60 Observations
  21. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  22. CFHTLS optical transient unlikely to be a GRB
  23. Unusual optical transient (GRB ???)
  24. GRB050117a: Refined analysis
  25. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  26. GRB050117: Palomar WIRC Ks-band observations
  27. GRB050117b: Swift-BAT detection of a weak burst
  28. GRB050117: optical observation
  29. GRB 050117, I-band observations
  30. GRB 050117: Optical observation
  31. GRB050117: MASTER optical observations
  32. GRB050117: Swift-BAT detection of a long multi-peaked burst
  33. GRB050117: Swift XRT Position
  34. Triangulation of Short Hard GRB050112 (large error box)
  35. SGR 1806-20: Further VLA Observations
  36. SGR 1806-20: Further low frequency GMRT results
  37. SGR 1806-20: Further VLA Observations
  38. SGR1806-20: Swift-BAT observations of two additional bursts
  39. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  40. Further VLA observations of SGR 1806-20
  41. SGR 1806-20 and extragalactic short-duration GRBs
  42. Further ATCA observations of SGR 1806-20
  43. Fourth Epoch VLA observations of SGR 1806-20
  44. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  45. SGR 1806-20: Temporal and Spectral behavior of radio transient
  46. ATCA observations of SGR 1806-20
  47. SGR 1806-20, RHESSI observations of the 041227 giant flare
  48. Third epoch observations of SGR 1806-20 with VLA
  49. Second Epoch VLA observations of SGR 1806-20
  50. Second-epoch VLA observations of SGR 1806-20
  51. SGR1806: Detection of a Sudden Ionospheric Disturbance
  52. VLA observations of SGR 1806-20
  53. SGR1806 VLA Observations
  54. VLA observations of SGR 1806-20
  55. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  56. GRB 041217: Optical observations
  57. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  58. GRB041219, early time observations
  59. Detection of the SGR 1806-20 giant outburst back-scattered by the
  60. The giant outburst from SGR 1806-20
  61. IPN localization of giant flare from SGR1806-20
  62. Giant flare from SGR 1806-20 detected by INTEGRAL
  63. GRB041228: ROTSE-III Optical Observations
  64. GRB041228: Swift-BAT detection of a burst
  65. GRB041219; RXTE ASM Observations
  66. NIR Observations of GRB 041219
  67. GRB041226: ROTSE-III Optical Observations
  68. GRB041226: Swift-BAT detection of a burst
  69. GRB041223: decay of the afterglow
  70. GRB041224: ROTSE-III Optical Observations
  71. GRB 041224: near-infrared observations with REM
  72. GRB 041223: XRT afterglow spectrum and light curve
  73. GRB 041223 Fluence measured by Swift-BAT
  74. GRB041224: Swift-BAT detection of a soft burst
  75. GRB041223: optical and NIR observations with REM
  76. Swift-BAT Time History of GRB041219
  77. GRB 041219: TAROT optical observations
  78. GRB 041218: TAROT optical observations
  79. GRB 041223: J-band observations of the afterglow
  80. GRB 041223: Detection of Optical Transient with LCO40
  81. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  82. GRB 041219c: PROMPT Observations
  83. GRB041223: ROTSE-III Optical Observations
  84. GRB041223: Swift-BAT detection of a bright long burst
  85. GRB 041218: optical observations
  86. Very high activity of SGR 1806-20
  87. GRB 041219: Second Epoch WSRT Radio Observations
  88. GRB 041219: WSRT Radio Afterglow Detection
  89. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  90. GRB 041218: Optical observations
  91. GRB 041219 : optical follow-up observations
  92. GRB041220: Swift-BAT burst
  93. Deep RAPTOR observations during GRB 041219
  94. GRB 041218 Optical Observations
  95. GRB 041219 Optical Observations
  96. GRB041219c: Third Burst in One Day from Swift-BAT
  97. GRB041219: Optical Afterglow Detection
  98. GRB041219: Continued NIR Observations
  99. GRB041219b: A Swift-BAT burst
  100. GRB 041219 ,optical observation

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