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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"
  1. GRB 140330A: intense and persistent gamma-ray emission detected by AGILE
  2. GRB 140331A: Zadko observatory - Gingin optical observations
  3. Konus-Wind observation of GRB 140330A
  4. GRB 140129B: AAO optical upper limit
  5. GRB 140129A: Mondy optical observations
  6. GRB 140331A: MITSuME Okayama upper limits
  7. GRB 140331A: Enhanced Swift-XRT position
  8. IPN triangulation of GRB 130330A
  9. GRB 140331A: RATIR Optical and NIR Observations
  10. GRB 140331A: Swift detection of a burst
  11. GRB 140330A: Fermi-LAT Detection
  12. GRB 140329A: Fermi-LAT detection
  13. Konus-Wind observation of GRB 140329A
  14. IPN Triangulation of GRB 140329A
  15. MAXI ID=745548350 is UV Ceti
  16. GRB 140320D: MASTER optical observations
  17. GRB 140329A: Fermi GBM observation of a bright burst
  18. Swift trigger 593744: detection of a flare from UV Cet
  19. GRB 140320D: Suzaku WAM observation of the prompt emission
  20. GRB 140323A : Suzaku WAM observation of the prompt emission
  21. Fermi Gamma-ray Burst Monitor trigger 417486540 / 140326020 is not a GRB
  22. GRB 140226A/iPTF14yb: Mondy optical observations
  23. GRB 140320C: Mondy optical observations and afterglow confirmation
  24. Konus-Wind observation of GRB 140323A
  25. GRB 140323A: Fermi-LAT detection
  26. GRB 140323A: Swift-XRT refined Analysis
  27. GRB 140323A: Fermi GBM observation
  28. GRB 140323A: BOOTES-3 optical upper limit.
  29. GRB 140323A: Swift/UVOT Upper Limits
  30. GRB 140323A: Swift-BAT refined analysis
  31. GRB 140323A: Enhanced Swift-XRT position
  32. GRB 140323A: Swift detection of a burst
  33. GRB 140320A: RATIR Optical and NIR Observations
  34. Konus-Wind observation of GRB 140320D
  35. GRB 140320B: P60 detection of a very red afterglow
  36. IPN Triangulation of very intense GRB 140320D
  37. GRB 140320C: Mini-GWAC prompt observation
  38. GRB 140320C: Swift/UVOT Upper Limits
  39. GRB 140320A: Swift-BAT refined analysis
  40. GRB 140320B: Swift/UVOT Upper Limits
  41. GRB 140320A: Swift/UVOT Upper Limits
  42. GRB 140320C: Swift-XRT observations
  43. GRB 140320A: Confirmation of a fading X-ray afterglow
  44. GRB 140320C: Swift-XRT detection of the X-ray afterglow
  45. GRB 140320A: Fermi GBM detection
  46. GRB 140320B: Swift-XRT detection of the afterglow
  47. GRB 140320C: Mondy optical observations
  48. GRB 140320A: Enhanced Swift-XRT position
  49. GRB 140320A: Swift-XRT detection of an afterglow candidate
  50. GRB 140320C: MASTER optical observations
  51. GRB 140320C: FTN optical observations
  52. GRB 140320C: A long GRB detected by INTEGRAL
  53. GRB 140320B: Xinglong TNT upper limit
  54. GRB 140320B: ISON-NM optical observations
  55. GRB 140320B: A long GRB detected by INTEGRAL
  56. GRB 140320B: FTN optical afterglow candidate
  57. Swift Trigger 592558 is not an astrophysical source
  58. GRB 140320A: Fermi GBM observations suggest a short GRB
  59. GRB 140320A: Swift detection of a burst
  60. GRB 140318A: Continued RATIR Optical and NIR Observations
  61. GRB 140318A: Mondy optical limit
  62. GRB 140318A: Swift/UVOT Upper Limits
  63. GRB 140318A: Swift-BAT refined analysis
  64. GRB 140311B: Mondy optical limit
  65. GRB 140311A: Mondy optical limits
  66. GRB 140318A: Swift-XRT refined Analysis
  67. GRB 140318A: Liverpool Telescope optical observations
  68. GRB 140318A: Enhanced Swift-XRT position
  69. GRB 140318A: RATIR Optical and NIR Detections
  70. GRB140318A: Discovery Channel Telescope Optical Detection
  71. GRB 140318A: WHT spectroscopy
  72. GRB 140318A: NOT detection of the afterglow
  73. GRB 140318A: Swift detection of a burst
  74. GRB 140311A: VLA Detection
  75. GRB140308A: Suzaku WAM observation of the prompt emission
  76. GRB 140311C: MASTER optical observations
  77. GRB 140311C: Swift-XRT and UVOT observations
  78. GRB 140311C: MASTER before, during and after trigger optical observations
  79. GRB 140311A: further NOT observations
  80. GRB 140311B: Swift-BAT refined analysis
  81. GRB 140311A: RATIR Optical and NIR Detection
  82. GRB 140311C: Fermi GBM Detection
  83. GRB 140311A: Montarrenti Observatory optical upper limit
  84. GRB 140311B: Fermi GBM Detection
  85. GRB 140311A: Kottamia I-band observation
  86. GRB 140311A: Swift/UVOT Upper Limits
  87. GRB 140311B: Swift/UVOT Upper Limits
  88. Fermi416242156: possible iPTF counterpart
  89. GRB 140311B: RATIR Optical and NIR Observations
  90. GRB 140311A: Bassano Bresciano Observatory optical upper limit
  91. GRB 140311A: Swift-XRT refined Analysis
  92. GRO J1744-28: Fermi GBM observation
  93. GRB 140311A: Gemini-North redshift
  94. GRB 140302A: GROND confirmation of the afterglow
  95. GRB 140311A: NOT redshift confirmation
  96. GRB 140311B: Swift-XRT refined Analysis
  97. GRB 140311A: Swift-BAT refined analysis
  98. GRB 140311A: Gemini-South redshift
  99. GRB 140311B: final MASTER OT light curve
  100. GRB 140311A: Enhanced Swift-XRT position

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