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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"

32502 results found.

  1. GRB 090817: No host galaxy, no supernova
  2. Konus-Wind observations of GRB 090823
  3. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  4. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  5. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  6. GRB 090820: MASTER-Net optical polarization observations
  7. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  8. GRB 090817: Liverpool Telescope Observations
  9. GRB 090817: optical upper limit
  10. GRB 090817: Confirmation of the X-ray afterglow
  11. GRB 090815C: Swift refined analysis
  12. GRB 090817: Fermi GBM observation
  13. GRB 090817: Swift/UVOT Upper Limits
  14. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  15. GRB 090813: I-band observations from 1.5m OSN telescope
  16. GRB 090817: Swift-XRT observations
  17. GRB 090814A: optical observations
  18. GRB 090813: Suzaku WAM observation of the prompt emission
  19. GRB 090812: Suzaku WAM observation of the prompt emission
  20. VLA radio non-detection of GRB 090812
  21. GRB 090813: CrAO optical obsevations
  22. GRB 090814B: Confirmation of the X-ray afterglow
  23. GRB090814A: NOT optical follow-ups
  24. GRB 090814B: I-band observations from 1.23m CAHA telescope
  25. GRB 090814B: Swift/UVOT Upper Limits
  26. GRB 090814B: Liverpool Telescope Observations
  27. GRB 090814B: Swift-XRT detection of a possible afterglow.
  28. GRB 090814A: Swift/UVOT Observations
  29. GRB 090814A: Swift-XRT Team Refined Analysis
  30. GRB 090814A, RIMOTS optical upper limits
  31. GRB 090814A: Swift-BAT refined analysis
  32. GRB 090813: correction to GCN 9787
  33. GRB090814A: VLT spectroscopy
  34. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  35. GRB 090813: Fermi GBM observation
  36. GRB 090813: Swift-XRT refined analysis
  37. GRB 090813, Swift-BAT refined analysis
  38. Konus-Wind observations of GRB090813
  39. GRB090813: Swift/UVOT upper limits
  40. GRB 090813: Liverpool Telescope afterglow confirmation
  41. GRB 090813: P60 Optical Afterglow Confirmation
  42. GRB 090813: optical candidate from 1.23m CAHA telescope
  43. GRB 090812: WIRO NIR upper limit
  44. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  45. GRB 090812: RAPTOR detections during the burst
  46. GRB 090812: Swift XRT refined analysis
  47. GRB 090812, RIMOTS optical upper limits
  48. GRB 090812 Swift-BAT Refined Analysis
  49. GRB090812: Swift/UVOT observations
  50. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  51. GRB 090812: Liverpool Telescope afterglow confirmation
  52. GRB 090812: P60 Confirmation of Optical Afterglow
  53. GRB 090809: Further NOT optical observations
  54. VLA radio upper limit on GRB 090809
  55. GRB 090621B: MAGIC telescope GeV observation
  56. GRB 090621A: MAGIC telescope GeV observation
  57. GRB 090809: WHT observations
  58. GRB 090809: Swift-XRT refined analysis
  59. GRB090809: Swift/UVOT observations
  60. GRB 090809: Swift-BAT refined analysis
  61. GRB 090809: afterglow confirmation at the NOT
  62. GRB 090807: Liverpool Telescope observations
  63. GRB 090807: MITSuME optical upper limit
  64. GRB 090807: Swift/UVOT Upper Limits
  65. GRB 090807: Swift-XRT refined analysis
  66. GRB 090807, Swift-BAT refined analysis
  67. GRB 090807, RIMOTS optical upper limits
  68. GRB 090726: optical observation
  69. Swift-BAT trigger 358760 is most likely not a GRB
  70. GRB 090717A: Suzaku WAM observation of the prompt emission
  71. GRB 090709A : Quick look analysis of the Suzaku observation
  72. GRB 090728: Swift-BAT refined analysis
  73. GRB 090727: GRT Optical Observation
  74. GRB 090728: Swift XRT refined analysis
  75. GRB 090727: optical observations
  76. GRB 090726: GRT Optical Observation
  77. GRB 090727: Swift/UVOT Upper Limits
  78. GRB 090728: Swift/UVOT Upper Limits
  79. GRB 090727: I-band observations from 1.23m CAHA
  80. GRB 090728, RIMOTS optical upper limits
  81. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  82. GRB 090727: Swift-BAT refined analysis
  83. GRB 090727: Swift-XRT refined analysis
  84. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  85. GRB 090715B: Late-time Lick 3m observations
  86. GRB 090727: Liverpool Telescope possible OT candidate
  87. GRB090726: Swift/UVOT observations
  88. GRB 090726, Swift-BAT refined analysis
  89. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  90. GRB 090726: D50 optical observations
  91. GRB090726: 6-meter telescope redshift
  92. GRB 090726: Swift-XRT Team refined analysis
  93. GRB 090726: optical transient candidate
  94. GRB 090726: Swift/UVOT Finding Chart Observation
  95. Konus-Wind and Konus-RF observations of GRB 090719
  96. Konus-RF and Konus-Wind observations of GRB 090718B
  97. Konus-Wind observations of bright hard GRB 090720B
  98. IPN Triangulation of bright GRB 090720B
  99. GRB 090720: Gemini-North Imaging and Optical Afterglow
  100. Swift XRT and UVOT refned analysis of GRB 090720

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