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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. Trigger 607399: Swift detection of SGR1806-20
  2. GRB 140723A: Swift-XRT and UVOT observations
  3. GRB 140723A: LCO-Sutherland optical candidate retraction
  4. GRB 140723A: MASTER optical observation
  5. Konus-Wind observation of GRB 140723A
  6. GRB 140723A: LCO-Sutherland optical candidate
  7. GRB 140723A: Fermi GBM detection
  8. IPN Triangulation of GRB 140723A
  9. GRB 140723A Tiled Swift observations
  10. GRB 140723A: Fermi-LAT detection
  11. GRB 140709B: Swift/UVOT Upper Limits
  12. Konus-Wind observation of GRB 140721A
  13. IPN Triangulation of GRB 140721A
  14. GRB 140719B: Swift XRT observation
  15. GRB 140719A: Swift/UVOT Upper Limits
  16. GRB 140721A: Fermi GBM detection
  17. GRB 140716A: Confirmation of the Swift-XRT afterglow
  18. GRB 140719B, Swift-BAT refined analysis
  19. GRB 140716A: GROND confirmation of the afterglow
  20. GRB 140719A, Swift-BAT refined analysis
  21. GRB 140719A: FTS observations
  22. GRB 140719A: GROND Afterglow candidate
  23. GRB 140719B: Zadko observatory - Gingin optical observations
  24. GRB 140719B: Swift detection of a burst
  25. GRB 140719A: Swift-XRT refined Analysis
  26. GRB 140719A: Enhanced Swift-XRT position
  27. GRB 140719A: Swift detection of a burst
  28. Konus-Wind observation of GRB 140716A
  29. GRB 140716A: Swift/UVOT Upper Limits
  30. GRB 140713A: AMI 15 GHz detection
  31. GRB 140713A: 10.4-m GTC deep optical observation
  32. GRB 140716A: GROND afterglow candidate
  33. GRB 140716A: Swift-XRT detection of an afterglow candidate
  34. GRB 140716A: A Fermi GBM Detection
  35. GRB 140716A BAT refined analysis
  36. Swift observations of a flare from UX Ari
  37. GRB 140716A found in ground analysis of Swift-BAT data
  38. GRB 140709A: Possible AMI 15 GHz detection
  39. Swift detection of UX Ari
  40. GRB 140713A: CARMA mm detection
  41. GRB 140714A: Fermi GBM detection
  42. Radio upper limits on the GRB 140703A with the GMRT
  43. GRB 140713A: Fermi GBM detection
  44. GRB 140713A: Swift-XRT refined Analysis
  45. GRB 140713A: Swift/UVOT Upper Limits
  46. GRB 140713A: NOT upper limits
  47. GRB 140713A : Xinglong TNT upper limit
  48. GRB 140713A: Enhanced Swift-XRT position
  49. GRB 140713A: Swift-BAT refined analysis
  50. GRB 140713A: T100 observations
  51. GRB 140710A: iTelescope.Net T11 Optical Observation
  52. GRB 140713A: Swift detection of a burst
  53. Swift Trigger 604111 is not a GRB
  54. GRB 140710B: Fermi GBM detection
  55. GRB 140710B: improved INTEGRAL position
  56. Fermi GBM Observations of SGR 1935+2154
  57. GRB 140710B: a long GRB detected with INTEGRAL
  58. GRB 140709A: Continued RATIR Optical and NIR Observations
  59. GRB 140710A: Swift-XRT refined Analysis
  60. GRB 140710A: Swift-BAT refined analysis
  61. GRB 140710A: Swift/UVOT Upper Limits
  62. GRB 140709B: update of Khureltogot optical upper limit
  63. GRB 140710A: Gemini-N redshift of likely host
  64. GRB 140710A: Enhanced Swift-XRT position
  65. GRB 140710A: RATIR Optical and NIR Observations
  66. GRB 140710A: P60 Confirmation of Afterglow
  67. GRB 140710A: correction to GCN #16565
  68. GRB 140710A: GROND Detection of NIR Afterglow Candidate
  69. GRB 140709A: 10.4m GTC optical decay
  70. GRB 140710A: Swift detection of a burst
  71. GRB 140709B: Swift-XRT refined Analysis
  72. GRB 140709B: Fermi GBM detection
  73. GRB 140709B: Swift-BAT refined analysis
  74. GRB 140709A : Virtual Telescope optical observations
  75. GRB 140709B: Khureltogot optical upper limit
  76. GRB 140709B: OSN optical limit
  77. GRB 140709B: Enhanced Swift-XRT position
  78. GRB 140709A: Fermi GBM detection
  79. GRB 140709A: BOOTES-2 and OSN optical observations
  80. GRB 140709A, Swift-BAT refined analysis
  81. GRB 140709B: MASTER optical observation
  82. GRB 140709B: Swift detection of a burst
  83. GRB 140709A: Swift-XRT refined Analysis
  84. GRB 140709A: Swift/UVOT Upper Limits
  85. GRB 140709A - UVOT-enhanced XRT position
  86. GRB 140709A: RATIR Optical and NIR Observations
  87. GRB 140709A: Swift detection of a burst
  88. Fermi GBM trigger 140708682 is not a GRB
  89. GRB 140705A: Nishi-Harima NIR upper limits
  90. GRB 140703A: AMI 15 GHz detection
  91. GRB 140705A / SGR 1935+2154: VLA 6 GHz observations
  92. GRB 140706A: Swift/UVOT Detection
  93. GRB 140703A: Swift/UVOT Upper Limits
  94. GRB 140706A: Swift-BAT refined analysis
  95. GRB 140706A: Swift-XRT refined Analysis
  96. GRB 140706A: Fermi GBM detection
  97. GRB 140703A: AAO optical observations
  98. Pre-discovery observations of SGR 1935+2154 in Swift archival data
  99. GRB140706A: GROND detection of the Optical/NIR afterglow
  100. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8

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