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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"

25027 results found.

  1. GRB 060814: Refined analysis of the Swift-BAT burst
  2. GRB 060814: P60 Observations
  3. GRB 060814: P200 NIR Observations
  4. GRB060805B: optical observations
  5. GRB 060814: Swift XRT refined analysis
  6. GRB 060814: VLT optical limits
  7. GRB 060814 - SDSS Pre-Burst Observations
  8. GRB 060814: TAROT optical observations
  9. GRB 060814: Swift detection of a bright burst
  10. Konus-Wind observation of GRB 060813
  11. GRB 060813: Swift XRT refined analysis
  12. GRB 060813: Refined analysis of the Swift-BAT burst
  13. GRB 060813: Swift detection of a burst
  14. GRB051109B: Late-time Radio Observations
  15. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  16. GRB060807: Possible Highly Significant X-ray Emission Lines
  17. GRB 060729: An update on the Swift XRT and UVOT observations
  18. GRB060717: optical observations
  19. GRB060807: Optical limiting magnitudes
  20. GRB 060805B: XRT Team Analysis
  21. GRB060806 is similar to previous activity of SGR1806-20
  22. GRB 060807: XRT Team refined analysis
  23. GRB 060807: Refined analysis of the Swift-BAT burst
  24. GRB060807: optical afterglow candidate
  25. IPN triangulation of GRB060806 (long, exceptionally bright)
  26. GRB060807 - SDSS Pre-burst Observations
  27. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  28. GRB 060805B: Swift/UVOT Upper Limits
  29. GRB 060807, optical observation
  30. GRB 060807: Kanazawa R-band observation
  31. GRB 060807: Swift detection of a burst
  32. GRB060805 Liverpool Telescope observations
  33. GRB 060805: XRT Team Refined Analysis
  34. GRB 060805: Swift-BAT Refined Analysis
  35. GRB 060805: Swift/UVOT Upper Limits
  36. GRB 060805: P60 Observations
  37. GRB 060805 - SDSS Pre-Burst Observations
  38. GRB 060804: Swift UVOT observations
  39. GRB 060804: Swift-XRT Team Refined Analysis
  40. GRB 060804: Refined analysis of the Swift-BAT burst
  41. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  42. GRB 060728: Upper limits of the X-ray emission
  43. GRB 060801: no variability of optical sources
  44. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  45. GRB060801: Radio Observations
  46. GRB 051109B: Bright spiral host galaxy at low redshift
  47. GRB060801: Swift/UVOT Upper Limits
  48. GRB 060801: optical observations at Hanle and Calar Alto
  49. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  50. GRB 060801, optical observation
  51. GRB 060801: Kanazawa Optical Observation
  52. GRB 060719: TORTOREM optical upper limits
  53. GRB 060729: Refined analysis of the Swift-BAT burst
  54. GRB 060729: Swift-XRT refined analysis
  55. GRB 060729: Swift/UVOT Observations
  56. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  57. GRB 060728: Swift/UVOT Upper Limits
  58. GRB 060728, SMARTS optical/IR observations
  59. Swift/XRT preliminary analysis
  60. GRB 060728: Swift detection of a burst
  61. GRB 060714: Swift/UVOT Observations
  62. GRB060719: prompt NIR observations with REM
  63. GRB 060714: NOT observations
  64. GRB 060719: near-infrared afterglow
  65. GRB 060719: correction to the coordinates reported in GCN 5347
  66. GRB 060522: VLA observation
  67. GRB 060719: Swift/UVOT Upper Limits
  68. GRB 060719: VLT/ISAAC observations
  69. GRB 060719: Refined analysis of the Swift-BAT burst
  70. GRB 060719: XRT refined analysis
  71. GRB 060719: further analysis of VLT observations
  72. GRB060719: REM NIR Observations
  73. GRB 060719: VLT observations
  74. GRB 060719: LCO optical observations
  75. GRB 060719: Swift detection of a burst
  76. GRB 060717: Swift XRT refined analysis
  77. GRB 060714: Refined analysis of the Swift-BAT burst
  78. GRB060717: Swift/UVOT upper limits
  79. GRB 060717: Swift-BAT refined analysis
  80. GRB060717 - SDSS Pre-burst Observations
  81. GRB 060714: REM infrared observations
  82. GRB 060717, optical observation
  83. GRB 060714 : Liverpool Telescope Observations
  84. GRB 060714: Swift XRT refined analysis
  85. GRB 060708: VLT spectroscopy
  86. Swift trigger 219136 is probably not a GRB
  87. GRB 060714, optical observation
  88. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  89. GRB060712: P60 Observations
  90. GRB 060712: XRT refined analysis
  91. GRB 060712: Swift/UVOT Upper Limits
  92. GRB060526: optical observations
  93. GRB 060712: XRT refined position
  94. GRB 060712: Refined analysis of the Swift-BAT burst
  95. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  96. GRB 060707: OA fading and redshift
  97. GRB 060708: Swift-XRT refined analysis
  98. GCN 060708: Swift-UVOT Observations
  99. GRB 060708: Refined analysis of the Swift-BAT burst
  100. GCN 060707: Swift-UVOT observations

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