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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"

42431 results found.

  1. GRB050117: MASTER optical observations
  2. GRB050117: Swift-BAT detection of a long multi-peaked burst
  3. GRB050117: Swift XRT Position
  4. Triangulation of Short Hard GRB050112 (large error box)
  5. SGR 1806-20: Further VLA Observations
  6. SGR 1806-20: Further low frequency GMRT results
  7. SGR 1806-20: Further VLA Observations
  8. SGR1806-20: Swift-BAT observations of two additional bursts
  9. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  10. Further VLA observations of SGR 1806-20
  11. SGR 1806-20 and extragalactic short-duration GRBs
  12. Further ATCA observations of SGR 1806-20
  13. Fourth Epoch VLA observations of SGR 1806-20
  14. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  15. SGR 1806-20: Temporal and Spectral behavior of radio transient
  16. ATCA observations of SGR 1806-20
  17. SGR 1806-20, RHESSI observations of the 041227 giant flare
  18. Third epoch observations of SGR 1806-20 with VLA
  19. Second Epoch VLA observations of SGR 1806-20
  20. Second-epoch VLA observations of SGR 1806-20
  21. SGR1806: Detection of a Sudden Ionospheric Disturbance
  22. VLA observations of SGR 1806-20
  23. SGR1806 VLA Observations
  24. VLA observations of SGR 1806-20
  25. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  26. GRB 041217: Optical observations
  27. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  28. GRB041219, early time observations
  29. Detection of the SGR 1806-20 giant outburst back-scattered by the
  30. The giant outburst from SGR 1806-20
  31. IPN localization of giant flare from SGR1806-20
  32. Giant flare from SGR 1806-20 detected by INTEGRAL
  33. GRB041228: ROTSE-III Optical Observations
  34. GRB041228: Swift-BAT detection of a burst
  35. GRB041219; RXTE ASM Observations
  36. NIR Observations of GRB 041219
  37. GRB041226: ROTSE-III Optical Observations
  38. GRB041226: Swift-BAT detection of a burst
  39. GRB041223: decay of the afterglow
  40. GRB041224: ROTSE-III Optical Observations
  41. GRB 041224: near-infrared observations with REM
  42. GRB 041223: XRT afterglow spectrum and light curve
  43. GRB 041223 Fluence measured by Swift-BAT
  44. GRB041224: Swift-BAT detection of a soft burst
  45. GRB041223: optical and NIR observations with REM
  46. Swift-BAT Time History of GRB041219
  47. GRB 041219: TAROT optical observations
  48. GRB 041218: TAROT optical observations
  49. GRB 041223: J-band observations of the afterglow
  50. GRB 041223: Detection of Optical Transient with LCO40
  51. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  52. GRB 041219c: PROMPT Observations
  53. GRB041223: ROTSE-III Optical Observations
  54. GRB041223: Swift-BAT detection of a bright long burst
  55. GRB 041218: optical observations
  56. Very high activity of SGR 1806-20
  57. GRB 041219: Second Epoch WSRT Radio Observations
  58. GRB 041219: WSRT Radio Afterglow Detection
  59. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  60. GRB 041218: Optical observations
  61. GRB 041219 : optical follow-up observations
  62. GRB041220: Swift-BAT burst
  63. Deep RAPTOR observations during GRB 041219
  64. GRB 041218 Optical Observations
  65. GRB 041219 Optical Observations
  66. GRB041219c: Third Burst in One Day from Swift-BAT
  67. GRB041219: Optical Afterglow Detection
  68. GRB041219: Continued NIR Observations
  69. GRB041219b: A Swift-BAT burst
  70. GRB 041219 ,optical observation
  71. GRB 041219: Radio Afterglow Detection
  72. GRB 041218 : Radio Observations
  73. GRB 041218: R-band optical observations
  74. GRB041218: Liverpool Telescope optical observations
  75. GRB041218: 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: NIR and optical observations with REM
  97. GRB041217: P60 Optical Observations
  98. GRB041217: Infrared Observations
  99. GRB041217: The First GRB Located On-Board Swift
  100. GRB041211: Faulkes Telescope continued optical monitoring

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