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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. Swift Trigger 1125354 (GRB 220926A) is not a GRB
  2. Swift GRB220926.34: Global MASTER-Net observations report
  3. Swift GRB 220926A: Global MASTER-Net observations report
  4. Analysis of long GRB 220926B detected by INTEGRAL
  5. GRB 220926B
  6. GRB 220926A: Swift detection of a burst
  7. Fermi GRB 220925A: Global MASTER-Net observations report
  8. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  9. GRB 220921A: further MeerLICHT observations
  10. GRB 220925A: Fermi GBM Final Real-time Localization
  11. Fermi trigger No 685748699: Global MASTER-Net observations report
  12. GRB 220924A: Fermi GBM Final Real-time Localization
  13. Swift GRB220923.47: Global MASTER-Net observations report
  14. GRB 220921A: ALMA detection
  15. GRB 220921A: DDOTI Detection of the Afterglow
  16. Konus-Wind detection of GRB 220921A
  17. GRB 220921A: Fermi GBM detection
  18. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  19. GRB 220921A: MeerLICHT afterglow observations
  20. GRB 220921A: Swift-XRT Observations
  21. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  22. LAT GRB220921.46: Global MASTER-Net observations report
  23. GRB 220921A: Fermi-LAT detection
  24. GRB 220921A: Tiled Swift observations
  25. Fermi trigger No 685452089: Global MASTER-Net observations report
  26. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  27. IceCube-220918A: Upper limits from a search for additional neutrino events in IceCube
  28. IceCube Alert 220918.53: Global MASTER-Net observations report
  29. IceCube-220918A - IceCube observation of a high-energy neutrino candidate track-like event
  30. Fermi trigger No 684894705: Global MASTER-Net observations report
  31. IceCube-220907A: No significant detection in HAWC
  32. Improved IPN error box for GRB 220910A
  33. Fermi trigger No 684927323: Global MASTER-Net observations report
  34. Fermi trigger No 684911625: Global MASTER-Net observations report
  35. GRB 220909A: Fermi GBM observation
  36. Konus-Wind detection of GRB 220910A
  37. GRB 220910B: Fermi GBM Final Localization
  38. Fermi trigger No 684716840: Global MASTER-Net observations report
  39. Fermi GRB 220912A: Global MASTER-Net observations report
  40. GRB 220910A: Fermi GBM observation
  41. IPN triangulation of GRB 220910A (bright/long)
  42. GRB 220912A: AstroSat CZTI detection
  43. GRB 220831A: DECam optical counterpart follow-up
  44. GRB 220909A: Swift-XRT observations
  45. GRB 220912A: Fermi GBM Final Real-time Localization
  46. IPN triangulation of GRB 220905A
  47. GRB 220909A: Swift ToO observations
  48. GRB 220909A: Swift/BAT-GUANO candidate arcminute localization
  49. GRB 220831A: Gemini-South Infrared Observations
  50. GRB 220910A: AstroSat CZTI detection
  51. GRB 220910A: AGILE detection
  52. GRB 220909A: Fermi GBM Final Real-time Localization
  53. IceCube-220907A: Upper limits from a search for additional neutrino events in IceCube
  54. GRB 220907A: Swift-BAT refined analysis
  55. IceCube-220907A: One Candidate Counterpart from the Zwicky Transient Facility
  56. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  57. IPN triangulation of GRB 220903A (long)
  58. GRB 220907A: Fermi GBM observation
  59. GRB 220907A: Nanshan/NEXT optical upper limits
  60. GRB 220907A: Swift/UVOT Upper Limits
  61. GRB 220907A: Swift-XRT refined Analysis
  62. GRB 220831A: ATCA 5/9 GHz radio observations
  63. Fermi-LAT Gamma-ray Observations of IceCube-220907A
  64. GRB 220907A: Swift-XRT position
  65. GRB 220907A: Swift detection of a burst
  66. GRB 220907A: Fermi GBM Final Real-time Localization
  67. Swift GRB220907.59: Global MASTER-Net observations report
  68. IceCube-220907A - IceCube observation of a high-energy neutrino candidate track-like event
  69. IceCube Alert 220907.28: Global MASTER-Net observations report
  70. GRB 220831A: Swift-UVOT Upper Limits
  71. Fermi GRB 220905A: Global MASTER-Net observations report
  72. GRB 220905A: BALROG localization (Fermi Trigger 684070128 / GRB 220905478)
  73. GRB 220905A: Fermi GBM Final Real-time Localization
  74. Introducing Self-Service Configuration of GCN Notices over Email for Transient Alerts
  75. GRB 220831A: DECam detection of a possible optical counterpart
  76. Fermi GRB 220902A: Global MASTER-Net observations report
  77. GRB 220902A: Fermi GBM Final Real-time Localization
  78. GRB 220831A, VLT/HAWK-I near-infrared observations
  79. GRB 220831C: Fermi GBM Final Localization
  80. GRB 220831A: Fermi GBM observation
  81. GRB 220831A: Swift-XRT observations
  82. GRB 220831B: Fermi GBM Final Localization
  83. GRB 220831A: Swift ToO observations
  84. Fermi trigger No 683654200: Global MASTER-Net observations report
  85. GRB 220831A: Swift/BAT-GUANO localization of a short burst
  86. Fermi trigger No 683646997: Global MASTER-Net observations report
  87. IceCube-220822A: No significant detection in HAWC
  88. Fermi trigger No 683537972: Global MASTER-Net observations report
  89. Fermi GBM trigger 683571622/220830709 is not a GRB
  90. Fermi trigger No 683476673: Global MASTER-Net observations report
  91. Konus-Wind detection of GRB 220826A
  92. IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
  93. IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
  94. GRB 220827A: Fermi GBM Final Real-time Localization
  95. GRB 220826A: Swift-BAT refined analysis
  96. GRB 220826A: Fermi GBM observation
  97. Fermi trigger No 683202084: Global MASTER-Net observations report
  98. Fermi trigger No 683183601: Global MASTER-Net observations report
  99. Fermi trigger No 683152759: Global MASTER-Net observations report
  100. GRB 220826A: Swift-XRT refined Analysis

Advanced

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