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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"

32508 results found.

  1. GRB 090827: Swift XRT and UVOT observations
  2. GRB 090817 - TLS Observations
  3. GRB090817: Keck/LRIS Spectroscopy
  4. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  5. GRB 090823: Confirmation of Swift-BAT position by BAT Slew Survey
  6. GRB 090823 Correction to BAT position
  7. GRB 090817: No host galaxy, no supernova
  8. Konus-Wind observations of GRB 090823
  9. GRB 090817: Swift/UVOT Observations of a Possible Late-Time Brightening
  10. GRB 090820: detection of a strong burst by RT-2 on board CORONAS PHOTON
  11. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  12. GRB 090820: MASTER-Net optical polarization observations
  13. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  14. GRB 090817: Liverpool Telescope Observations
  15. GRB 090817: optical upper limit
  16. GRB 090817: Confirmation of the X-ray afterglow
  17. GRB 090815C: Swift refined analysis
  18. GRB 090817: Fermi GBM observation
  19. GRB 090817: Swift/UVOT Upper Limits
  20. GRB 090812: Konus-Wind and Swift/BAT joint spectral analysis
  21. GRB 090813: I-band observations from 1.5m OSN telescope
  22. GRB 090817: Swift-XRT observations
  23. GRB 090814A: optical observations
  24. GRB 090813: Suzaku WAM observation of the prompt emission
  25. GRB 090812: Suzaku WAM observation of the prompt emission
  26. VLA radio non-detection of GRB 090812
  27. GRB 090813: CrAO optical obsevations
  28. GRB 090814B: Confirmation of the X-ray afterglow
  29. GRB090814A: NOT optical follow-ups
  30. GRB 090814B: I-band observations from 1.23m CAHA telescope
  31. GRB 090814B: Swift/UVOT Upper Limits
  32. GRB 090814B: Liverpool Telescope Observations
  33. GRB 090814B: Swift-XRT detection of a possible afterglow.
  34. GRB 090814A: Swift/UVOT Observations
  35. GRB 090814A: Swift-XRT Team Refined Analysis
  36. GRB 090814A, RIMOTS optical upper limits
  37. GRB 090814A: Swift-BAT refined analysis
  38. GRB 090813: correction to GCN 9787
  39. GRB090814A: VLT spectroscopy
  40. GRB 090814: GROND Detection of an Optical Afterglow Candidate
  41. GRB 090813: Fermi GBM observation
  42. GRB 090813: Swift-XRT refined analysis
  43. GRB 090813, Swift-BAT refined analysis
  44. Konus-Wind observations of GRB090813
  45. GRB090813: Swift/UVOT upper limits
  46. GRB 090813: Liverpool Telescope afterglow confirmation
  47. GRB 090813: P60 Optical Afterglow Confirmation
  48. GRB 090813: optical candidate from 1.23m CAHA telescope
  49. GRB 090812: WIRO NIR upper limit
  50. GRB 090812: Faulkes Telescope South Continued Optical Monitoring
  51. GRB 090812: RAPTOR detections during the burst
  52. GRB 090812: Swift XRT refined analysis
  53. GRB 090812, RIMOTS optical upper limits
  54. GRB 090812 Swift-BAT Refined Analysis
  55. GRB090812: Swift/UVOT observations
  56. GRB 090812: GROND Observations of the Optical/NIR Afterglow
  57. GRB 090812: Liverpool Telescope afterglow confirmation
  58. GRB 090812: P60 Confirmation of Optical Afterglow
  59. GRB 090809: Further NOT optical observations
  60. VLA radio upper limit on GRB 090809
  61. GRB 090621B: MAGIC telescope GeV observation
  62. GRB 090621A: MAGIC telescope GeV observation
  63. GRB 090809: WHT observations
  64. GRB 090809: Swift-XRT refined analysis
  65. GRB090809: Swift/UVOT observations
  66. GRB 090809: Swift-BAT refined analysis
  67. GRB 090809: afterglow confirmation at the NOT
  68. GRB 090807: Liverpool Telescope observations
  69. GRB 090807: MITSuME optical upper limit
  70. GRB 090807: Swift/UVOT Upper Limits
  71. GRB 090807: Swift-XRT refined analysis
  72. GRB 090807, Swift-BAT refined analysis
  73. GRB 090807, RIMOTS optical upper limits
  74. GRB 090726: optical observation
  75. Swift-BAT trigger 358760 is most likely not a GRB
  76. GRB 090717A: Suzaku WAM observation of the prompt emission
  77. GRB 090709A : Quick look analysis of the Suzaku observation
  78. GRB 090728: Swift-BAT refined analysis
  79. GRB 090727: GRT Optical Observation
  80. GRB 090728: Swift XRT refined analysis
  81. GRB 090727: optical observations
  82. GRB 090726: GRT Optical Observation
  83. GRB 090727: Swift/UVOT Upper Limits
  84. GRB 090728: Swift/UVOT Upper Limits
  85. GRB 090727: I-band observations from 1.23m CAHA
  86. GRB 090728, RIMOTS optical upper limits
  87. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  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 090715B: Late-time Lick 3m observations
  92. GRB 090727: Liverpool Telescope possible OT candidate
  93. GRB090726: Swift/UVOT observations
  94. GRB 090726, Swift-BAT refined analysis
  95. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  96. GRB 090726: D50 optical observations
  97. GRB090726: 6-meter telescope redshift
  98. GRB 090726: Swift-XRT Team refined analysis
  99. GRB 090726: optical transient candidate
  100. GRB 090726: Swift/UVOT Finding Chart Observation

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