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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-220822A: No significant detection in HAWC
  2. Fermi trigger No 683537972: Global MASTER-Net observations report
  3. Fermi GBM trigger 683571622/220830709 is not a GRB
  4. Fermi trigger No 683476673: Global MASTER-Net observations report
  5. Konus-Wind detection of GRB 220826A
  6. IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
  7. IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
  8. GRB 220827A: Fermi GBM Final Real-time Localization
  9. GRB 220826A: Swift-BAT refined analysis
  10. GRB 220826A: Fermi GBM observation
  11. Fermi trigger No 683202084: Global MASTER-Net observations report
  12. Fermi trigger No 683183601: Global MASTER-Net observations report
  13. Fermi trigger No 683152759: Global MASTER-Net observations report
  14. GRB 220826A: Swift-XRT refined Analysis
  15. GRB 220825A: Fermi GBM observation
  16. GRB 220826A: Lesedi optical afterglow detection
  17. GRB 220826A: Swift/UVOT Detection
  18. GRB 220826A: iTelescope optical afterglow observations
  19. Swift GRB 220826A: Global MASTER-Net observations report
  20. GRB 220826A: Enhanced Swift-XRT position
  21. GRB 220826A: Swift detection of a burst with an optical counterpart
  22. GRB 220825A: Swift/BAT-GUANO detection
  23. GRB 220825A: Fermi GBM Final Localization
  24. IceCube-220822A: Upper limits from a search for additional neutrino events in IceCube
  25. IceCube-220822A: One Candidate Counterpart from the Zwicky Transient Facility
  26. GRB 220823A: Fermi GBM detection
  27. Fermi-LAT gamma-ray observations of IceCube-220822A and detection of a new gamma-ray source, Fermi J1810.1+2154
  28. Fermi trigger No 682918137: Global MASTER-Net observations report
  29. GRB 220823A: Swift/BAT-GUANO detection of a short burst
  30. IceCube-220822A - IceCube observation of a high-energy neutrino candidate track-like event
  31. IceCube Alert 220822.85: Global MASTER-Net observations report
  32. GRB 220821A: Fermi GBM Final Real-time Localization
  33. Konus-Wind detection of GRB 220813A
  34. GRB 220813A: VLT optical observations and possible host galaxy
  35. GRB 220813A: Swift/UVOT Detection
  36. GRB 220810A: Further Swift-XRT observations
  37. GRB 220813A: Swift-XRT refined Analysis
  38. Swift GRB 220813A: Global MASTER-Net observations report
  39. GRB 220813A: Enhanced Swift-XRT position
  40. GRB 220813A: Swift detection of a burst with an optical counterpart
  41. GRB 220810A: Swift-XRT observations
  42. GRB 220719B: Detection by VZLUSAT-2
  43. Fermi trigger No 681998863: Global MASTER-Net observations report
  44. GRB 220810A: Swift ToO observations
  45. GRB 220810A: MeerLICHT detection of two afterglow candidates
  46. Fermi GBM trigger 681998863/220812505 is not a GRB
  47. Fermi trigger No 681890304: Global MASTER-Net observations report
  48. Fermi GBM trigger 681890304/220811249 is not a GRB
  49. Fermi GRB 220810A: Global MASTER-Net observations report
  50. GRB 220810A: Fermi GBM Final Real-time Localization
  51. GRB 220627A: MeerKAT radio observations
  52. GRB 220806A: Swift-BAT refined analysis
  53. Fermi trigger No 681719116: Global MASTER-Net observations report
  54. Fermi GBM trigger 681719116/220809267 is not a GRB
  55. Fermi trigger No 681633544: Global MASTER-Net observations report
  56. IceCube Astrotrack Bronze 136918_45252263.amon is likely background
  57. Fermi GBM trigger 681633544/220808277 is not a GRB
  58. IceCube Alert 220808.33: Global MASTER-Net observations report
  59. Fermi GBM trigger 681547990 / 220807287 is not a GRB
  60. GRB 220806A: Swift detection of a burst
  61. Swift GRB220806.76: Global MASTER-Net observations report
  62. GRB 220804A: Fermi GBM Final Localization
  63. Fermi trigger No 681271717: Global MASTER-Net observations report
  64. GRB 220803A: AstroSat CZTI detection
  65. Fermi trigger No 681212354: Global MASTER-Net observations report
  66. Konus-Wind detection of GRB 220730A (short)
  67. GRB 220730A: Swift-BAT refined analysis
  68. GRB 220730A: Fermi GBM detection
  69. GRB 220730A: Swift-XRT afterglow detection
  70. GRB 220730A: Swift/UVOT Upper Limits
  71. GRB 220730A: Swift-XRT observations
  72. GRB 220729A: AstroSat CZTI detection
  73. Swift GRB 220730A: Global MASTER-Net observations report
  74. GRB 220730A: Swift detection of a short hard burst
  75. Fermi trigger No 680782656: Global MASTER-Net observations report
  76. Fermi GRB 220728A: Global MASTER-Net observations report
  77. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-220728A
  78. GRB 220728A: Fermi GBM Final Real-time Localization
  79. GRB 220726A: Fermi GBM Final Real-time Localization
  80. Fermi trigger No 680421061: Global MASTER-Net observations report
  81. Fermi GRB 220724A: Global MASTER-Net observations report
  82. GRB 220724A: Fermi GBM Final Real-time Localization
  83. GRB 220715B: VIRT Optical Upper Limit
  84. Fermi GRB 220721A: Global MASTER-Net observations report
  85. GRB 220721A: Fermi GBM Final Real-time Localization
  86. Introducing new GCN Kafka broker and web site for transient alerts, https://gcn.nasa.gov
  87. Retraction: Fermi GBM trigger 679932336.585264/220719587 is not a GRB
  88. GRB 220715A: CALET Gamma-Ray Burst Monitor detection
  89. GRB 220711B: CALET Gamma-Ray Burst Monitor detection
  90. GRB 220719A: Fermi GBM Final Real-time Localization
  91. GRB 220715B: Swift-BAT refined analysis
  92. GRB220714B: UVOT detections
  93. GRB 220715B: Fermi GBM detection
  94. GRB 220715B: Swift-XRT refined Analysis
  95. GRB 220715B: Swift/UVOT Upper Limits
  96. GRB 220715B: Enhanced Swift-XRT position
  97. GRB 220715B: BOOTES-network optical upper limits
  98. Swift GRB 220715B: Global MASTER-Net observations report
  99. GRB 220715B: Prompt enhanced Swift-XRT position
  100. GRB 220715B: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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