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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"

26042 results found.

  1. GRB060813: Swift/UVOT upper limits
  2. GRB 060813: Swift XRT refined analysis
  3. GRB 060813: Refined analysis of the Swift-BAT burst
  4. GRB 060813: Swift detection of a burst
  5. GRB051109B: Late-time Radio Observations
  6. Image of the dust-scattering halo around SGR 1806-20
  7. A dust-scattering halo detected around SGR 1806-20
  8. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  9. GRB060807: Possible Highly Significant X-ray Emission Lines
  10. GRB060714: optical observations
  11. GRB 060729: An update on the Swift XRT and UVOT observations
  12. GRB060717: optical observations
  13. GRB060807: Optical limiting magnitudes
  14. GRB 060805B: optical observation at Sierra Nevada
  15. GRB 060805B: XRT Team Analysis
  16. GRB 060807: UVOT Upper limits
  17. GRB 060807: afterglow confirmation
  18. GRB 060807: XRT Team refined analysis
  19. GRB 060807: Refined analysis of the Swift-BAT burst
  20. GRB060807: optical afterglow candidate
  21. GRB060807: optical upper limit in white light
  22. IPN triangulation of GRB060806 (long, exceptionally bright)
  23. GRB060807 - SDSS Pre-burst Observations
  24. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  25. GRB 060805B: Swift/UVOT Upper Limits
  26. GRB 060807: Kanazawa R-band observation
  27. GRB 060807: optical limit
  28. GRB 060807: Swift detection of a burst
  29. GRB 060801: Second Epoch WSRT Radio Observations
  30. GRB060805 Liverpool Telescope observations
  31. GRB 060805: optical upper limit in R
  32. GRB 060805: XRT Team Refined Analysis
  33. GRB 060805: Swift-BAT Refined Analysis
  34. GRB 060805: Swift/UVOT Upper Limits
  35. GRB 060805: P60 Observations
  36. GRB 060805: KAIT observations
  37. GRB 060805 - SDSS Pre-Burst Observations
  38. GRB 060805: Swift detection of a burst
  39. GRB 060804: Swift UVOT observations
  40. GRB 060804: Swift-XRT Team Refined Analysis
  41. GRB 060804: Refined analysis of the Swift-BAT burst
  42. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  43. GRB 060728: Upper limits of the X-ray emission
  44. GRB 060801: no variability of optical sources
  45. GRB 060801: WSRT Radio Observations
  46. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  47. GRB060801: Radio Observations
  48. GRB 051109B: Bright spiral host galaxy at low redshift
  49. GRB 060801: optical observations at FORS2/VLT
  50. GRB060801: Swift/UVOT Upper Limits
  51. GRB 060801: optical observations at Hanle and Calar Alto
  52. GRB060801: optical upper limit in R
  53. GRB 060801: Swift XRT refined analysis
  54. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  55. GRB 060801: Kanazawa Optical Observation
  56. GRB 060801: Swift detection of a short burst
  57. GRB060729: ROTSE-III Observations of the Slow Optical Decay
  58. Swift-BAT trigger 221873 is not a GRB or a Transient
  59. GRB 060729 redshift
  60. GRB 060729: Swift/UVOT Detections
  61. GRB 060729: Refined analysis of the Swift-BAT burst
  62. GRB 060729: Swift-XRT refined analysis
  63. GRB 060729: Swift/UVOT Observations
  64. GRB 060729: ROTSE-III Detection of Optical Counterpart
  65. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  66. GRB 060728: Swift/UVOT Upper Limits
  67. GRB 060728: Refined analysis of the Swift-BAT burst
  68. Swift/XRT preliminary analysis
  69. GRB 060728: Swift detection of a burst
  70. GRB060614 ATCA Radio Limits
  71. GRB 060218 (SN 2006aj): IR afterglow detection six months after the
  72. GRB 060714: Swift/UVOT Observations
  73. GRB060719: prompt NIR observations with REM
  74. GRB 060714: NOT observations
  75. GRB 060719: near-infrared afterglow
  76. GRB 060522: VLA observation
  77. GRB 060719: Swift/UVOT Upper Limits
  78. GRB 060719: VLT/ISAAC observations
  79. GRB 060719: Refined analysis of the Swift-BAT burst
  80. GRB 060719: XRT refined analysis
  81. GRB 060719: further analysis of VLT observations
  82. GRB 060719: optical limit by Pi-of-the-Sky
  83. GRB060719: FRAM early follow-up limit
  84. GRB 060719: prompt PROMPT observations
  85. GRB060719: REM NIR Observations
  86. GRB 060719: Continued LCO optical observations
  87. GRB 060719: LCO optical observations
  88. GRB 060719: Swift detection of a burst
  89. GRB 060717: Swift XRT refined analysis
  90. GRB 060714: OA fading and a possible host detection
  91. GRB060714: optical observations
  92. GRB 060717: NOT observations
  93. GRB 060714: Refined analysis of the Swift-BAT burst
  94. GRB 060717 optical upper limit
  95. GRB060717: Swift/UVOT upper limits
  96. GRB 060717: Swift XRT refined position
  97. GRB 060717: Swift-BAT refined analysis
  98. GRB 060714: REM infrared observations
  99. GRB 060717: Swift detection of a burst
  100. GRB060714: optical observations

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