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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

19129 results found.

  1. GRB060805B: optical observations
  2. GRB060814: Swift/UVOT upper limits
  3. GRB 060813: pseudo-z from spectral parameters of the prompt
  4. GRB 060814: Swift XRT refined analysis
  5. GRB 060814 - SDSS Pre-Burst Observations
  6. GRB 060814: TAROT optical observations
  7. GRB 060814: Swift detection of a bright burst
  8. Konus-Wind observation of GRB 060813
  9. GRB060813: Swift/UVOT upper limits
  10. GRB 060813: Swift XRT refined analysis
  11. GRB 060813: Refined analysis of the Swift-BAT burst
  12. GRB 060813: Swift detection of a burst
  13. Image of the dust-scattering halo around SGR 1806-20
  14. A dust-scattering halo detected around SGR 1806-20
  15. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  16. GRB060714: optical observations
  17. GRB 060729: An update on the Swift XRT and UVOT observations
  18. GRB060807: Optical limiting magnitudes
  19. GRB 060805B: optical observation at Sierra Nevada
  20. GRB 060805B: XRT Team Analysis
  21. GRB 060807: UVOT Upper limits
  22. GRB 060807: XRT Team refined analysis
  23. GRB 060807: Refined analysis of the Swift-BAT burst
  24. IPN triangulation of GRB060806 (long, exceptionally bright)
  25. GRB060807 - SDSS Pre-burst Observations
  26. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  27. GRB 060805B: Swift/UVOT Upper Limits
  28. GRB 060807: Swift detection of a burst
  29. GRB 060805: XRT Team Refined Analysis
  30. GRB 060805: Swift-BAT Refined Analysis
  31. GRB 060805: Swift/UVOT Upper Limits
  32. GRB 060805: KAIT observations
  33. GRB 060805 - SDSS Pre-Burst Observations
  34. GRB 060805: Swift detection of a burst
  35. GRB 060804: Swift UVOT observations
  36. GRB 060804: Swift-XRT Team Refined Analysis
  37. GRB 060804: Refined analysis of the Swift-BAT burst
  38. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  39. GRB 060728: Upper limits of the X-ray emission
  40. GRB 060801: WSRT Radio Observations
  41. GRB060801: Radio Observations
  42. GRB060801: Swift/UVOT Upper Limits
  43. GRB 060801: optical observations at Hanle and Calar Alto
  44. GRB 060801: Swift XRT refined analysis
  45. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  46. GRB 060801: Swift detection of a short burst
  47. GRB060729: ROTSE-III Observations of the Slow Optical Decay
  48. Swift-BAT trigger 221873 is not a GRB or a Transient
  49. GRB 060729: Swift/UVOT Detections
  50. GRB 060729: Refined analysis of the Swift-BAT burst
  51. GRB 060729: Swift-XRT refined analysis
  52. GRB 060729: Swift/UVOT Observations
  53. GRB 060729: ROTSE-III Detection of Optical Counterpart
  54. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  55. GRB 060728: Swift/UVOT Upper Limits
  56. GRB 060728: Refined analysis of the Swift-BAT burst
  57. Swift/XRT preliminary analysis
  58. GRB 060728: Swift detection of a burst
  59. GRB060614 ATCA Radio Limits
  60. GRB 060714: Swift/UVOT Observations
  61. GRB 060522: VLA observation
  62. GRB 060719: Swift/UVOT Upper Limits
  63. GRB 060719: Refined analysis of the Swift-BAT burst
  64. GRB 060719: XRT refined analysis
  65. GRB 060719: optical limit by Pi-of-the-Sky
  66. GRB060719: FRAM early follow-up limit
  67. GRB 060719: Swift detection of a burst
  68. GRB 060717: Swift XRT refined analysis
  69. GRB 060714: Refined analysis of the Swift-BAT burst
  70. GRB060717: Swift/UVOT upper limits
  71. GRB 060717: Swift XRT refined position
  72. GRB 060717: Swift-BAT refined analysis
  73. GRB 060717: Swift detection of a burst
  74. GRB 060714: Swift XRT refined analysis
  75. GRB060708: MARGE low resolution spectrum observations
  76. Swift-BAT trigger 219136 is not a GRB
  77. GRB060707 possible optical confirmation
  78. Swift trigger 219136 is probably not a GRB
  79. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  80. GRB 060712: XRT refined analysis
  81. GRB 060712: Swift/UVOT Upper Limits
  82. GRB 060712: XRT refined position
  83. GRB 060712: Refined analysis of the Swift-BAT burst
  84. GRB 060712: Swift detection of a burst
  85. GRB 060708: Swift-XRT refined analysis
  86. GCN 060708: Swift-UVOT Observations
  87. GRB 060708: Refined analysis of the Swift-BAT burst
  88. GCN 060707: Swift-UVOT observations
  89. GRB 060707: Swift-XRT refined analysis
  90. GRB 060708: Swift detection of a burst with an UVOT countpart
  91. GRB060707 possible optical confirmation
  92. GRB 060707: BOOTES-IR optical afterglow candidate
  93. GRB 060707: Refined analysis of the Swift-BAT burst
  94. GRB 060707: BOOTES-IR optical observation
  95. GRB060614: Possible SN Bump in UVOT U Band Light Curve
  96. GRB 060707: Swift detection of a burst
  97. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  98. Swift-BAT trigger 215279 is not a GRB
  99. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  100. GRB 060614: pseudo-z from spectral parameters of the prompt emission

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