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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"

28201 results found.

  1. GRB 090814B: Confirmation of the X-ray afterglow
  2. GRB090814A: NOT optical follow-ups
  3. GRB 090814B: I-band observations from 1.23m CAHA telescope
  4. GRB 090814B: Swift/UVOT Upper Limits
  5. GRB 090814B: Liverpool Telescope Observations
  6. GRB 090814C: Fermi GBM detection
  7. GRB 090814B: Swift-XRT detection of a possible afterglow.
  8. GRB 090814A: Swift/UVOT Observations
  9. GRB 090814A: Swift-XRT Team Refined Analysis
  10. GRB090814A: VLT spectroscopy
  11. GRB 090814: Enhanced Swift-XRT position
  12. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  13. GRB 090814: Swift detection of a burst
  14. GRB 090813: Swift-XRT refined analysis
  15. GRB090813: Swift/UVOT upper limits
  16. GRB 090813: Enhanced Swift-XRT position
  17. GRB 090813: Liverpool Telescope afterglow confirmation
  18. GRB 090813: P60 Optical Afterglow Confirmation
  19. GRB 090813: optical candidate from 1.23m CAHA telescope
  20. GRB 090813: Swift detection of a burst
  21. GRB 090812: WIRO NIR upper limit
  22. GRB 090812: Swift XRT refined analysis
  23. GRB090812: Swift/UVOT observations
  24. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  25. GRB 090812: Enhanced Swift-XRT position
  26. GRB 090812 VLT redshift
  27. GRB 090812: Liverpool Telescope afterglow confirmation
  28. GRB 090812: P60 Confirmation of Optical Afterglow
  29. GRB 090812: Swift detection of a burst with an optical counterpart
  30. GRB 090807B: Fermi GBM detection
  31. GRB 090809: Further NOT optical observations
  32. VLA radio upper limit on GRB 090809
  33. GRB 090809: WHT observations
  34. GRB 090809 X-shooter redshift
  35. GRB 090809B: Fermi GBM detection
  36. GRB 090809: Swift-XRT refined analysis
  37. GRB090809: Swift/UVOT observations
  38. GRB 090809: Enhanced Swift-XRT position
  39. GRB 090809: afterglow confirmation at the NOT
  40. GRB 090809: Swift detection of a burst with a possible optical counterpart
  41. GRB 090807: Liverpool Telescope observations
  42. GRB 090807: MITSuME optical upper limit
  43. GRB 090807: Swift/UVOT Upper Limits
  44. GRB 090807: Swift-XRT refined analysis
  45. GRB 090807, Swift-BAT refined analysis
  46. GRB 090807: Enhanced Swift-XRT position
  47. GRB 090807: Swift detection of a burst
  48. GRB 090802B: Fermi GBM detection
  49. GRB 090802: Fermi GBM detection
  50. GRB 090726: optical observation
  51. Swift-BAT trigger 358760 is most likely not a GRB
  52. Swift trigger 358760 is probably a noise event
  53. GRB 090709A : Quick look analysis of the Suzaku observation
  54. GRB 090727: GRT Optical Observation
  55. GRB 090728: Swift XRT refined analysis
  56. GRB 090727: optical observations
  57. GRB 090726: GRT Optical Observation
  58. GRB 090727: Swift/UVOT Upper Limits
  59. GRB 090728: Swift/UVOT Upper Limits
  60. GRB 090728: Enhanced Swift-XRT position
  61. GRB 090727: I-band observations from 1.23m CAHA
  62. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  63. GRB 090728: Swift detection of a burst
  64. GRB 090727: Swift-XRT refined analysis
  65. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  66. GRB 090727: Enhanced Swift-XRT position
  67. GRB 090715B: Late-time Lick 3m observations
  68. GRB 090727: Liverpool Telescope possible OT candidate
  69. GRB 090727: Swift detection of a burst
  70. GRB090726: Swift/UVOT observations
  71. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  72. GRB 090726: D50 optical observations
  73. GRB 090711: Fermi GBM detection
  74. GRB090726: 6-meter telescope redshift
  75. GRB 090726: Swift-XRT Team refined analysis
  76. GRB 090726: Enhanced Swift-XRT position
  77. GRB 090726: optical transient candidate
  78. GRB 090726: Swift/UVOT Finding Chart Observation
  79. GRB 090726: Swift-XRT position of probable counterpart
  80. GRB 090726: Swift detection of a burst
  81. GRB 090720: Gemini-North Imaging and Optical Afterglow
  82. GRB 090720B: Fermi GBM detection
  83. Swift XRT and UVOT refned analysis of GRB 090720
  84. GRB 090709A: Swift XRT Timing Analysis
  85. GRB 090715B: VLA radio detection
  86. GRB 090717B: Fermi GBM detection
  87. GRB 090717: Fermi GBM detection
  88. GRB 090719: Fermi GBM detection
  89. GRB 090718B: Fermi GBM detection
  90. GRB 090718: Fermi GBM detection
  91. GRB 090720: Fermi GBM detection
  92. GRB 090715B: further NOT optical observations
  93. GRB 090709A - CARMA mm Observations
  94. GRB 090715B: Swift/UVOT followup observations
  95. GRB 090715B: break in the optical afterglow decay
  96. GRB 090715B: Enhanced Swift-XRT position
  97. GRB 090715B: Observation of the optical afterglow
  98. GRB 090715B: Swift XRT Refined Analysis
  99. GRB090715B: WHT redshift
  100. GRB 090715B: NOT optical observations

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