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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"

26310 results found.

  1. GRB 090829B: Fermi GBM Detection
  2. GRB 090831C: Enhanced Swift-XRT position
  3. GRB 090831C: Swift detection of a burst
  4. GRB 090831: MAXI GSC detection
  5. GRB 090831B: Swift detection of a possible burst
  6. GRB 090831: Fermi GBM detection
  7. GRB090829: Fermi GBM Detection
  8. Konus-Wind observations of GRB 090827
  9. GRB 090827 Burst discovered in BAT ground analysis
  10. GRB 090826: Fermi GBM detection
  11. GRB 090828: Fermi GBM detection
  12. GRB090817: Keck/LRIS Spectroscopy
  13. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  14. GRB 090823: Confirmation of Swift-BAT position by BAT Slew Survey
  15. GRB 090823 Correction to BAT position
  16. GRB 090817: No host galaxy, no supernova
  17. Konus-Wind observations of GRB 090823
  18. GRB 090823 Long burst with IPN triangulation and BAT position
  19. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  20. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  21. GRB 090820B: Fermi GBM detection
  22. GRB 090820: Fermi GBM Detection of a bright burst.
  23. GRB 090817: Confirmation of the X-ray afterglow
  24. GRB 090815C: Swift refined analysis
  25. GRB 090817: Fermi GBM observation
  26. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  27. GRB 090817: Swift-XRT observations
  28. GRB 090813: Suzaku WAM observation of the prompt emission
  29. GRB 090812: Suzaku WAM observation of the prompt emission
  30. GRB 090817: a long GRB localized by INTEGRAL
  31. VLA radio non-detection of GRB 090812
  32. GRB 090815B: Fermi GBM detection
  33. GRB 090815: Fermi GBM detection
  34. GRB 090814B: Confirmation of the X-ray afterglow
  35. GRB 090814B: I-band observations from 1.23m CAHA telescope
  36. GRB 090814C: Fermi GBM detection
  37. GRB 090814A: Swift-XRT Team Refined Analysis
  38. GRB 090814A: Swift-BAT refined analysis
  39. GRB090814A: VLT spectroscopy
  40. GRB 090814: Enhanced Swift-XRT position
  41. GRB 090814B: a long GRB localized by INTEGRAL
  42. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  43. GRB 090814: Swift detection of a burst
  44. GRB 090813: Fermi GBM observation
  45. GRB 090813: Swift-XRT refined analysis
  46. GRB 090813, Swift-BAT refined analysis
  47. Konus-Wind observations of GRB090813
  48. GRB090813: Swift/UVOT upper limits
  49. GRB 090813: Enhanced Swift-XRT position
  50. GRB 090813: Liverpool Telescope afterglow confirmation
  51. GRB 090813: P60 Optical Afterglow Confirmation
  52. GRB 090813: Swift detection of a burst
  53. GRB 090812: WIRO NIR upper limit
  54. GRB 090812: Swift XRT refined analysis
  55. GRB 090812 Swift-BAT Refined Analysis
  56. GRB090812: Swift/UVOT observations
  57. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  58. GRB 090812: Enhanced Swift-XRT position
  59. GRB 090812: Liverpool Telescope afterglow confirmation
  60. GRB 090812: P60 Confirmation of Optical Afterglow
  61. GRB 090812: Swift detection of a burst with an optical counterpart
  62. GRB 090807B: Fermi GBM detection
  63. VLA radio upper limit on GRB 090809
  64. GRB 090621B: MAGIC telescope GeV observation
  65. GRB 090621A: MAGIC telescope GeV observation
  66. GRB 090809B: Fermi GBM detection
  67. GRB 090809: Swift-XRT refined analysis
  68. GRB090809: Swift/UVOT observations
  69. GRB 090809: Enhanced Swift-XRT position
  70. GRB 090809: Swift-BAT refined analysis
  71. GRB 090809: Swift detection of a burst with a possible optical counterpart
  72. GRB 090807: MITSuME optical upper limit
  73. GRB 090807: Swift-XRT refined analysis
  74. GRB 090807, Swift-BAT refined analysis
  75. GRB 090807: Enhanced Swift-XRT position
  76. GRB 090807: Swift detection of a burst
  77. IPN Triangulation and Konus-Wind observaions of GRB090727B
  78. GRB 090802: Fermi GBM detection
  79. GRB 090726: optical observation
  80. GRB 090717A: Suzaku WAM observation of the prompt emission
  81. GRB 090709A : Quick look analysis of the Suzaku observation
  82. GRB 090728: Swift-BAT refined analysis
  83. GRB 090727: GRT Optical Observation
  84. GRB 090728: Swift XRT refined analysis
  85. GRB 090726: GRT Optical Observation
  86. GRB 090728: Enhanced Swift-XRT position
  87. GRB 090728: Swift detection of a burst
  88. GRB 090727: Swift-BAT refined analysis
  89. GRB 090727: Swift-XRT refined analysis
  90. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  91. GRB 090727: Enhanced Swift-XRT position
  92. GRB 090715B: Late-time Lick 3m observations
  93. GRB 090727: Liverpool Telescope possible OT candidate
  94. GRB 090727: Swift detection of a burst
  95. GRB090726: Swift/UVOT observations
  96. GRB 090726, Swift-BAT refined analysis
  97. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  98. GRB 090726: D50 optical observations
  99. GRB 090711: Fermi GBM detection
  100. GRB 090726: Swift-XRT Team refined analysis

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