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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"

23404 results found.

  1. GRB 090404: optical observations at BOOTES-3 and 1.5-m OSN
  2. GRB 090404: Swift-XRT Team refined analysis
  3. GRB 090404: Xinglong TNT optical Upper Limit
  4. GRB 090404: Enhanced Swift-XRT position
  5. GRB 090404: Swift detection of a burst
  6. GRB 090401A: Suzaku WAM observation of the prompt emission
  7. GRB 090401B: Xinglong TNT optical Upper Limit
  8. GRB 090401B: VLA radio upper limit
  9. GRB 090401B: Upper limits of MITSuME optical observation
  10. GRB090401B, RIMOTS optical upper limits
  11. Swift/UVOT observations of GRB090401B
  12. Swift/UVOT observations of GRB090401B
  13. GRB 090331: Fermi GBM detection
  14. GRB 090401B: Enhanced Swift-XRT position
  15. AGILE Gamma-ray detection of GRB 090401B
  16. GRB 090401B: Swift detection of a burst
  17. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  18. GRB 090401: Swift detection of a burst
  19. GRB 090328: Radio afterglow detection
  20. GRB 090326: Fermi GBM detection
  21. GRB 090328: BOOTES-3 optical observations
  22. GRB 090328B: Fermi GBM Detection
  23. GRB 090330: Fermi GBM detection
  24. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  25. GRB090323: Optical observations from NOT
  26. GRB 090328: IPN Triangulation
  27. GRB 090328: Swift UVOT observations
  28. GRB 090328: Updated position/optical afterglow candidate
  29. GRB 090323: Radio afterglow detection
  30. GRB 090327: Fermi GBM detection
  31. GRB 090320B: MASTER-Net prompt optical observations
  32. GRB 090323: UVOT Detection of Afterglow
  33. GRB 090323: Swift-XRT refined analysis
  34. GRB 090324: SuperAGILE Localization of a Long GRB
  35. GRB 090323: P60 Afterglow Confirmation
  36. GRB 090323: GROND Detection of the Afterglow and Photo-z
  37. GRB 090323: Possible XRT Counterpart
  38. IPN triangulation of GRB090323
  39. GRB 090320C: Fermi GBM Detection
  40. GRB 090320B: Fermi GBM detection.
  41. GRB 090319: Fermi GBM detection
  42. GRB 090320A: Fermi GBM detection
  43. Further 15GHz observations of GRB090313
  44. X-shooter observations of GRB 090313
  45. GRB090313: radio detection with the VLA
  46. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  47. Further radio observation of GRB 090313
  48. Further Swift/UVOT observations of GRB 090313
  49. GRB 090313: detection with CARMA in 3mm band
  50. GRB090305B: MASTER-net prompt optical short burst observations
  51. GRB 090313: MITSuME Okayama observation
  52. GRB 090313: Additional Gemini-S photometry
  53. GRB 090313: TAROT La Silla observatory optical detection
  54. GRB 090313: Zadko Telescope observations
  55. GRB 090313 optical observations
  56. GRB 090313: Ongoing plateau phase
  57. GRB 090313: Swift-XRT refined analysis
  58. GRB 090313: Swift/UVOT upper limits
  59. GRB 090313: Sustained optical brightness (correction)
  60. GRB 090306B: Confirmation of the X-ray afterglow
  61. GRB 090313, GROND observations
  62. GRB 090309, Swift-BAT lag analysis
  63. GRB 090313: Swift detection of a burst
  64. GRB 090313: Swift detection of a burst
  65. Swift trigger 346250 is probably not a burst
  66. GRB090310: Fermi GBM detection
  67. GRB 090205: Zadko Telescope late-time observations
  68. GRB 090309A: GROND upper limits
  69. GRB 090307A: TAROT Calern observatory optical observations
  70. GRB 090309: Swift/UVOT Upper Limits
  71. GRB090305B: Fermi GBM detection
  72. GRB 090309B: Fermi GBM detection
  73. GRB 090309: Enhanced Swift-XRT position
  74. GRB 090308: GROND observations
  75. GRB 090308: Gemini GMOS Observations
  76. GRB 090309: Swift detection of a burst
  77. GRB 090308B: Fermi GBM detection
  78. GRB 090308: Swift/UVOT Upper Limits
  79. GRB 090307B: Fermi GBM detection
  80. GRB 090306C: Fermi GBM detection
  81. GRB 090307: GROND Upper Limits
  82. GRB 090306B: GROND Upper Limits
  83. GRB 090308: Swift-XRT refined analysis
  84. GRB 090308: Swift detection of a burst
  85. GRB 090306B: Possible XRT afterglow
  86. GRB 090307: Swift-XRT afterglow confirmation and analysis
  87. Swift Trigger 345551 is probably not a GRB
  88. IPN localization of short GRB 090305C
  89. GRB 090306: Swift detection of a possible burst
  90. GRB 090305: Swift/UVOT Upper Limits
  91. GRB 090305: Swift-XRT refined analysis
  92. GRB090305: GMOS-S Candidate Optical Afterglow
  93. GRB 090305: Swift detection of a short burst
  94. GRB 090303: Fermi GBM detection
  95. GRB 090304: Fermi GBM detection
  96. Konus-RF catches first GRB and SGR bursts
  97. GRB 090228B: Fermi GBM detection
  98. IPN localization of short bright GRB 090227B
  99. GRB 090301B: Fermi GBM detection
  100. GRB 090227B: Fermi GBM detection

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