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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"

28114 results found.

  1. GRB051109B: Late-time Radio Observations
  2. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  3. GRB060807: Possible Highly Significant X-ray Emission Lines
  4. GRB 060729: An update on the Swift XRT and UVOT observations
  5. GRB060717: optical observations
  6. GRB060807: Optical limiting magnitudes
  7. GRB 060805B: XRT Team Analysis
  8. GRB060806 is similar to previous activity of SGR1806-20
  9. GRB 060807: XRT Team refined analysis
  10. GRB 060807: Refined analysis of the Swift-BAT burst
  11. GRB060807: optical afterglow candidate
  12. IPN triangulation of GRB060806 (long, exceptionally bright)
  13. GRB060807 - SDSS Pre-burst Observations
  14. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  15. GRB 060805B: Swift/UVOT Upper Limits
  16. GRB 060807, optical observation
  17. GRB 060807: Kanazawa R-band observation
  18. GRB 060807: Swift detection of a burst
  19. GRB060805 Liverpool Telescope observations
  20. GRB 060805: XRT Team Refined Analysis
  21. GRB 060805: Swift-BAT Refined Analysis
  22. GRB 060805: Swift/UVOT Upper Limits
  23. GRB 060805: P60 Observations
  24. GRB 060805 - SDSS Pre-Burst Observations
  25. GRB 060804: Swift UVOT observations
  26. GRB 060804: Swift-XRT Team Refined Analysis
  27. GRB 060804: Refined analysis of the Swift-BAT burst
  28. GRB 060804: Swift detection of a burst with a possible UVOT counterpart
  29. GRB 060728: Upper limits of the X-ray emission
  30. GRB 060801: no variability of optical sources
  31. GRB 060801: XRT/SDSS Frame Offset and Refined XRT Position
  32. GRB060801: Radio Observations
  33. GRB 051109B: Bright spiral host galaxy at low redshift
  34. GRB060801: Swift/UVOT Upper Limits
  35. GRB 060801: optical observations at Hanle and Calar Alto
  36. GRB 060801: Refined analysis of the Swift-BAT short hard burst
  37. GRB 060801, optical observation
  38. GRB 060801: Kanazawa Optical Observation
  39. GRB 060719: TORTOREM optical upper limits
  40. GRB 060729: Refined analysis of the Swift-BAT burst
  41. GRB 060729: Swift-XRT refined analysis
  42. GRB 060729: Swift/UVOT Observations
  43. GRB 060729: Swift detection of a burst with an UVOT optical counterpart
  44. GRB 060728: Swift/UVOT Upper Limits
  45. GRB 060728, SMARTS optical/IR observations
  46. Swift/XRT preliminary analysis
  47. GRB 060728: Swift detection of a burst
  48. GRB 060714: Swift/UVOT Observations
  49. GRB060719: prompt NIR observations with REM
  50. GRB 060714: NOT observations
  51. GRB 060719: near-infrared afterglow
  52. GRB 060719: correction to the coordinates reported in GCN 5347
  53. GRB 060522: VLA observation
  54. GRB 060719: Swift/UVOT Upper Limits
  55. GRB 060719: VLT/ISAAC observations
  56. GRB 060719: Refined analysis of the Swift-BAT burst
  57. GRB 060719: XRT refined analysis
  58. GRB 060719: further analysis of VLT observations
  59. GRB060719: REM NIR Observations
  60. GRB 060719: VLT observations
  61. GRB 060719: LCO optical observations
  62. GRB 060719: Swift detection of a burst
  63. GRB 060717: Swift XRT refined analysis
  64. GRB 060714: Refined analysis of the Swift-BAT burst
  65. GRB060717: Swift/UVOT upper limits
  66. GRB 060717: Swift-BAT refined analysis
  67. GRB060717 - SDSS Pre-burst Observations
  68. GRB 060714: REM infrared observations
  69. GRB 060717, optical observation
  70. GRB 060714 : Liverpool Telescope Observations
  71. GRB 060714: Swift XRT refined analysis
  72. GRB 060708: VLT spectroscopy
  73. Swift trigger 219136 is probably not a GRB
  74. GRB 060714, optical observation
  75. GRB 060714: Swift detection of a burst with an UVOT optical afterglow
  76. GRB060712: P60 Observations
  77. GRB 060712: XRT refined analysis
  78. GRB 060712: Swift/UVOT Upper Limits
  79. GRB060526: optical observations
  80. GRB 060712: XRT refined position
  81. GRB 060712: Refined analysis of the Swift-BAT burst
  82. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  83. GRB 060707: OA fading and redshift
  84. GRB 060708: Swift-XRT refined analysis
  85. GCN 060708: Swift-UVOT Observations
  86. GRB 060708: Refined analysis of the Swift-BAT burst
  87. GCN 060707: Swift-UVOT observations
  88. GRB 060707: Swift-XRT refined analysis
  89. GRB 060708: Swift detection of a burst with an UVOT countpart
  90. GRB 060707: Refined analysis of the Swift-BAT burst
  91. GRB 060707: BOOTES-IR optical observation
  92. GRB 060515: Upper Limit on Host Galaxy
  93. GRB 060614: SMARTS host galaxy observations
  94. GRB 060614: Detection of a Possible, Late-Time Rebrightening
  95. GRB 060109: Upper Limit on Host Galaxy
  96. GRB 060105: Upper limit on Host Galaxy
  97. GRB 060614: Redshift
  98. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  99. GRB050326: Host Galaxy Candidates
  100. GRB050124: Possible Host Galaxy

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