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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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. IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
  2. Konus-Wind detection of GRB 220927A
  3. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  4. Fermi GRB 220927A: Global MASTER-Net observations report
  5. IPN triangulation of GRB 220927A (long)
  6. GRB 220921A: LCOGT Optical Observations
  7. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  8. GRB 220927A: Fermi GBM Final Localization
  9. GRB 220924A: Fermi GBM detection
  10. Integral GRB220926.44: Global MASTER-Net observations report
  11. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  12. Swift Trigger 1125354 (GRB 220926A) is not a GRB
  13. Swift GRB220926.34: Global MASTER-Net observations report
  14. Swift GRB 220926A: Global MASTER-Net observations report
  15. Analysis of long GRB 220926B detected by INTEGRAL
  16. GRB 220926B
  17. GRB 220926A: Swift detection of a burst
  18. Fermi GRB 220925A: Global MASTER-Net observations report
  19. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  20. GRB 220921A: further MeerLICHT observations
  21. GRB 220925A: Fermi GBM Final Real-time Localization
  22. Fermi trigger No 685748699: Global MASTER-Net observations report
  23. GRB 220924A: Fermi GBM Final Real-time Localization
  24. Swift GRB220923.47: Global MASTER-Net observations report
  25. GRB 220921A: ALMA detection
  26. GRB 220921A: DDOTI Detection of the Afterglow
  27. Konus-Wind detection of GRB 220921A
  28. GRB 220921A: Fermi GBM detection
  29. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  30. GRB 220921A: MeerLICHT afterglow observations
  31. GRB 220921A: Swift-XRT Observations
  32. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  33. LAT GRB220921.46: Global MASTER-Net observations report
  34. GRB 220921A: Fermi-LAT detection
  35. GRB 220921A: Tiled Swift observations
  36. Fermi trigger No 685452089: Global MASTER-Net observations report
  37. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  38. IceCube-220918A: Upper limits from a search for additional neutrino events in IceCube
  39. IceCube Alert 220918.53: Global MASTER-Net observations report
  40. IceCube-220918A - IceCube observation of a high-energy neutrino candidate track-like event
  41. Fermi trigger No 684894705: Global MASTER-Net observations report
  42. IceCube-220907A: No significant detection in HAWC
  43. Improved IPN error box for GRB 220910A
  44. Fermi trigger No 684927323: Global MASTER-Net observations report
  45. Fermi trigger No 684911625: Global MASTER-Net observations report
  46. GRB 220909A: Fermi GBM observation
  47. Konus-Wind detection of GRB 220910A
  48. GRB 220910B: Fermi GBM Final Localization
  49. Fermi trigger No 684716840: Global MASTER-Net observations report
  50. Fermi GRB 220912A: Global MASTER-Net observations report
  51. GRB 220910A: Fermi GBM observation
  52. IPN triangulation of GRB 220910A (bright/long)
  53. GRB 220912A: AstroSat CZTI detection
  54. GRB 220831A: DECam optical counterpart follow-up
  55. GRB 220909A: Swift-XRT observations
  56. GRB 220912A: Fermi GBM Final Real-time Localization
  57. IPN triangulation of GRB 220905A
  58. GRB 220909A: Swift ToO observations
  59. GRB 220909A: Swift/BAT-GUANO candidate arcminute localization
  60. GRB 220831A: Gemini-South Infrared Observations
  61. GRB 220910A: AstroSat CZTI detection
  62. GRB 220910A: AGILE detection
  63. GRB 220909A: Fermi GBM Final Real-time Localization
  64. IceCube-220907A: Upper limits from a search for additional neutrino events in IceCube
  65. GRB 220907A: Swift-BAT refined analysis
  66. IceCube-220907A: One Candidate Counterpart from the Zwicky Transient Facility
  67. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  68. IPN triangulation of GRB 220903A (long)
  69. GRB 220907A: Fermi GBM observation
  70. GRB 220907A: Nanshan/NEXT optical upper limits
  71. GRB 220907A: Swift/UVOT Upper Limits
  72. GRB 220907A: Swift-XRT refined Analysis
  73. GRB 220831A: ATCA 5/9 GHz radio observations
  74. Fermi-LAT Gamma-ray Observations of IceCube-220907A
  75. GRB 220907A: Swift-XRT position
  76. GRB 220907A: Swift detection of a burst
  77. GRB 220907A: Fermi GBM Final Real-time Localization
  78. Swift GRB220907.59: Global MASTER-Net observations report
  79. IceCube-220907A - IceCube observation of a high-energy neutrino candidate track-like event
  80. IceCube Alert 220907.28: Global MASTER-Net observations report
  81. GRB 220831A: Swift-UVOT Upper Limits
  82. Fermi GRB 220905A: Global MASTER-Net observations report
  83. GRB 220905A: BALROG localization (Fermi Trigger 684070128 / GRB 220905478)
  84. GRB 220905A: Fermi GBM Final Real-time Localization
  85. Introducing Self-Service Configuration of GCN Notices over Email for Transient Alerts
  86. GRB 220831A: DECam detection of a possible optical counterpart
  87. Fermi GRB 220902A: Global MASTER-Net observations report
  88. GRB 220902A: Fermi GBM Final Real-time Localization
  89. GRB 220831A, VLT/HAWK-I near-infrared observations
  90. GRB 220831C: Fermi GBM Final Localization
  91. GRB 220831A: Fermi GBM observation
  92. GRB 220831A: Swift-XRT observations
  93. GRB 220831B: Fermi GBM Final Localization
  94. GRB 220831A: Swift ToO observations
  95. Fermi trigger No 683654200: Global MASTER-Net observations report
  96. GRB 220831A: Swift/BAT-GUANO localization of a short burst
  97. Fermi trigger No 683646997: Global MASTER-Net observations report
  98. IceCube-220822A: No significant detection in HAWC
  99. Fermi trigger No 683537972: Global MASTER-Net observations report
  100. Fermi GBM trigger 683571622/220830709 is not a GRB

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