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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"

18786 results found.

  1. GRB060904b optical detections (delayed report due to internet outage)
  2. GRB 060906: Early RAPTOR optical limits
  3. GRB 060906, Swift-BAT refined spectral analysis
  4. GRB 060906: Swift/XRT Refined Analysis
  5. GRB 060906: Swift-UVOT observations
  6. VLT redshift of GRB 060906
  7. GRB 060906, Swift-BAT refined analysis
  8. GRB 060906: KAIT observations
  9. GRB 060906 (?): P60 Optical Afterglow Candidate
  10. GRB 060906: Swift detection of a probable burst
  11. GRB 060904A Milagro GeV/TeV Observations
  12. GRB060904A: Swift/UVOT optical observations
  13. GRB 060904A: pseudo-z from spectral parameters of the prompt emission
  14. GRB 060904B: Swift-BAT refined analysis
  15. GRB060904b: Optical observations with Swift/UVOT
  16. Konus-Wind observation of GRB 060904A
  17. GRB 060904B: Swift-XRT refined analysis
  18. GRB 060904A: Refined analysis of the Swift-BAT burst
  19. GRB 060904A: Swift-XRT refined analysis
  20. GRB 060904A: Suzaku-XIS and -HXD observation plan
  21. GRB 060904B: Optical observations at Crni Vrh
  22. GRB060904B: Watcher observations
  23. GRB 060904B BOOTES-IR and 1.5m OSN observations
  24. GRB 060904B: TAROT optical counterpart observations
  25. GRB060904B - SDSS Pre-Burst Observations
  26. GRB 060904: TAROT optical observations
  27. GRB 060904B: Swift detection of a burst with optical counterpart
  28. GRB 060904B: ROTSE-III Detection of Optical Counterpart
  29. GRB060904 - SDSS Pre-Burst Observations
  30. GRB 060904: Swift detection of a bright burst
  31. 060901: Swift UVOT followup observations
  32. GRB 060901: Swift/XRT Refined Analysis
  33. GRB 060901: Swift/XRT Position
  34. GRB 060604: VLA Observation
  35. GRB 060814: Suzaku/WAM observation of the prompt emission
  36. GRB 060605: VLA Observation
  37. GRB 060707: VLA observation
  38. GRB 060825: VLA observations
  39. GRB 060825: pseudo-z from spectral parameters of the prompt emission
  40. Swift-BAT trigger 226614 is not a GRB
  41. GRB060826 - SDSS Pre-Burst Observations
  42. GRB 060826(?): Swift detection of a possible burst
  43. GRB 060825: XRT Team Refined Analysis
  44. GRB 060825: Swift-BAT Refined Analysis
  45. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  46. GRB060825: Liverpool Telescope optical observations
  47. GRB 060825: TAROT optical observations
  48. GRB060825: BOOTES-IR optical observations
  49. GRB 060825: Swift detection of a burst
  50. GRB060729: analysis of XMM-Newton observation
  51. GRB 060814: pseudo-z from spectral parameters of the prompt
  52. Radio observations of GRB 060719
  53. GRB060814: Break in the XRT light curve
  54. GRB060813: Break in the XRT light curve
  55. GRB 060813: A long, bright GRB detected with Suzaku WAM
  56. Konus-Wind observation of GRB 060814
  57. GRB 060814: Refined analysis of the Swift-BAT burst
  58. GRB060805B: optical observations
  59. GRB060814: Swift/UVOT upper limits
  60. GRB 060813: pseudo-z from spectral parameters of the prompt
  61. GRB 060814: Swift XRT refined analysis
  62. GRB 060814 - SDSS Pre-Burst Observations
  63. GRB 060814: TAROT optical observations
  64. GRB 060814: Swift detection of a bright burst
  65. Konus-Wind observation of GRB 060813
  66. GRB060813: Swift/UVOT upper limits
  67. GRB 060813: Swift XRT refined analysis
  68. GRB 060813: Refined analysis of the Swift-BAT burst
  69. GRB 060813: Swift detection of a burst
  70. Image of the dust-scattering halo around SGR 1806-20
  71. A dust-scattering halo detected around SGR 1806-20
  72. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  73. GRB060714: optical observations
  74. GRB 060729: An update on the Swift XRT and UVOT observations
  75. GRB060807: Optical limiting magnitudes
  76. GRB 060805B: optical observation at Sierra Nevada
  77. GRB 060805B: XRT Team Analysis
  78. GRB 060807: UVOT Upper limits
  79. GRB 060807: XRT Team refined analysis
  80. GRB 060807: Refined analysis of the Swift-BAT burst
  81. IPN triangulation of GRB060806 (long, exceptionally bright)
  82. GRB060807 - SDSS Pre-burst Observations
  83. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  84. GRB 060805B: Swift/UVOT Upper Limits
  85. GRB 060807: Swift detection of a burst
  86. GRB 060805: XRT Team Refined Analysis
  87. GRB 060805: Swift-BAT Refined Analysis
  88. GRB 060805: Swift/UVOT Upper Limits
  89. GRB 060805: KAIT observations
  90. GRB 060805 - SDSS Pre-Burst Observations
  91. GRB 060805: Swift detection of a burst
  92. GRB 060804: Swift UVOT observations
  93. GRB 060804: Swift-XRT Team Refined Analysis
  94. GRB 060804: Refined analysis of the Swift-BAT burst
  95. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  96. GRB 060728: Upper limits of the X-ray emission
  97. GRB 060801: WSRT Radio Observations
  98. GRB060801: Radio Observations
  99. GRB060801: Swift/UVOT Upper Limits
  100. GRB 060801: optical observations at Hanle and Calar Alto

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