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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"

45438 results found.

  1. GRB 090826: Fermi GBM detection
  2. GRB 090828: Fermi GBM detection
  3. Fermi Gamma-ray Burst Monitor trigger 273123112 is not a GRB
  4. GRB 090817 - TLS Observations
  5. GRB090817: Keck/LRIS Spectroscopy
  6. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  7. GRB 090823: Confirmation of Swift-BAT position by BAT Slew Survey
  8. GRB 090823 Correction to BAT position
  9. GRB 090817: No host galaxy, no supernova
  10. Konus-Wind observations of GRB 090823
  11. GRB 090823 Long burst with IPN triangulation and BAT position
  12. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  13. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  14. GRB 090820B: Fermi GBM detection
  15. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  16. GRB 090820: MASTER-Net optical polarization observations
  17. GRB 090820: Fermi GBM Detection of a bright burst.
  18. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  19. GRB 090817: Liverpool Telescope Observations
  20. GRB 090817: optical upper limit
  21. GRB 090817: Confirmation of the X-ray afterglow
  22. GRB 090815C: Swift refined analysis
  23. GRB 090817: Fermi GBM observation
  24. GRB 090817: Swift/UVOT Upper Limits
  25. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  26. GRB 090813: I-band observations from 1.5m OSN telescope
  27. GRB 090817: Swift-XRT observations
  28. GRB 090814A: optical observations
  29. GRB 090813: Suzaku WAM observation of the prompt emission
  30. GRB 090812: Suzaku WAM observation of the prompt emission
  31. GRB 090817: a long GRB localized by INTEGRAL
  32. VLA radio non-detection of GRB 090812
  33. GRB 090815B: Fermi GBM detection
  34. GRB 090815: Fermi GBM detection
  35. GRB 090813: CrAO optical obsevations
  36. GRB 090814B: Confirmation of the X-ray afterglow
  37. GRB090814A: NOT optical follow-ups
  38. GRB 090814B: I-band observations from 1.23m CAHA telescope
  39. GRB 090814B: Swift/UVOT Upper Limits
  40. GRB 090814B: Liverpool Telescope Observations
  41. Fermi Gamma-ray Burst Monitor trigger 271934815 is not a GRB
  42. GRB 090814C: Fermi GBM detection
  43. GRB 090814B: Swift-XRT detection of a possible afterglow.
  44. GRB 090814A: Swift/UVOT Observations
  45. GRB 090814A: Swift-XRT Team Refined Analysis
  46. GRB 090814A, RIMOTS optical upper limits
  47. GRB 090814A: Swift-BAT refined analysis
  48. GRB 090813: correction to GCN 9787
  49. GRB090814A: VLT spectroscopy
  50. GRB 090814: Enhanced Swift-XRT position
  51. GRB 090814B: a long GRB localized by INTEGRAL
  52. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  53. GRB 090814: Swift detection of a burst
  54. GRB 090813: Fermi GBM observation
  55. Fermi Gamma-ray Burst Monitor trigger 271446248 is not a GRB
  56. GRB 090813: Swift-XRT refined analysis
  57. Fermi Gamma-ray Burst Monitor trigger 271833016 is not a GRB
  58. GRB 090813, Swift-BAT refined analysis
  59. Konus-Wind observations of GRB090813
  60. GRB090813: Swift/UVOT upper limits
  61. GRB 090813: Enhanced Swift-XRT position
  62. GRB 090813: Liverpool Telescope afterglow confirmation
  63. GRB 090813: P60 Optical Afterglow Confirmation
  64. GRB 090813: optical candidate from 1.23m CAHA telescope
  65. GRB 090813: Swift detection of a burst
  66. GRB 090812: WIRO NIR upper limit
  67. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  68. GRB 090812: RAPTOR detections during the burst
  69. GRB 090812: Swift XRT refined analysis
  70. GRB 090812, RIMOTS optical upper limits
  71. GRB 090812 Swift-BAT Refined Analysis
  72. GRB090812: Swift/UVOT observations
  73. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  74. GRB 090812: Enhanced Swift-XRT position
  75. GRB 090812 VLT redshift
  76. GRB 090812: Liverpool Telescope afterglow confirmation
  77. GRB 090812: P60 Confirmation of Optical Afterglow
  78. GRB 090812: Swift detection of a burst with an optical counterpart
  79. GRB 090807B: Fermi GBM detection
  80. GRB 090809: Further NOT optical observations
  81. VLA radio upper limit on GRB 090809
  82. GRB 090621B: MAGIC telescope GeV observation
  83. GRB 090621A: MAGIC telescope GeV observation
  84. GRB 090809: WHT observations
  85. GRB 090809 X-shooter redshift
  86. GRB 090809B: Fermi GBM detection
  87. GRB 090809: Swift-XRT refined analysis
  88. GRB090809: Swift/UVOT observations
  89. GRB 090809: Enhanced Swift-XRT position
  90. GRB 090809: Swift-BAT refined analysis
  91. GRB 090809: afterglow confirmation at the NOT
  92. GRB 090809: Swift detection of a burst with a possible optical counterpart
  93. GRB 090807: Liverpool Telescope observations
  94. GRB 090807: MITSuME optical upper limit
  95. GRB 090807: Swift/UVOT Upper Limits
  96. GRB 090807: Swift-XRT refined analysis
  97. GRB 090807, Swift-BAT refined analysis
  98. GRB 090807: Enhanced Swift-XRT position
  99. GRB 090807, RIMOTS optical upper limits
  100. GRB 090807: Swift detection of a burst

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