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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. GRB 220831A: Fermi GBM observation
  2. GRB 220831A: Swift-XRT observations
  3. GRB 220831B: Fermi GBM Final Localization
  4. GRB 220831A: Swift ToO observations
  5. Fermi trigger No 683654200: Global MASTER-Net observations report
  6. GRB 220831A: Swift/BAT-GUANO localization of a short burst
  7. Fermi trigger No 683646997: Global MASTER-Net observations report
  8. IceCube-220822A: No significant detection in HAWC
  9. Fermi trigger No 683537972: Global MASTER-Net observations report
  10. Fermi GBM trigger 683571622/220830709 is not a GRB
  11. Fermi trigger No 683476673: Global MASTER-Net observations report
  12. Konus-Wind detection of GRB 220826A
  13. IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
  14. IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
  15. GRB 220827A: Fermi GBM Final Real-time Localization
  16. GRB 220826A: Swift-BAT refined analysis
  17. GRB 220826A: Fermi GBM observation
  18. Fermi trigger No 683202084: Global MASTER-Net observations report
  19. Fermi trigger No 683183601: Global MASTER-Net observations report
  20. Fermi trigger No 683152759: Global MASTER-Net observations report
  21. GRB 220826A: Swift-XRT refined Analysis
  22. GRB 220825A: Fermi GBM observation
  23. GRB 220826A: Lesedi optical afterglow detection
  24. GRB 220826A: Swift/UVOT Detection
  25. GRB 220826A: iTelescope optical afterglow observations
  26. Swift GRB 220826A: Global MASTER-Net observations report
  27. GRB 220826A: Enhanced Swift-XRT position
  28. GRB 220826A: Swift detection of a burst with an optical counterpart
  29. GRB 220825A: Swift/BAT-GUANO detection
  30. GRB 220825A: Fermi GBM Final Localization
  31. IceCube-220822A: Upper limits from a search for additional neutrino events in IceCube
  32. IceCube-220822A: One Candidate Counterpart from the Zwicky Transient Facility
  33. GRB 220823A: Fermi GBM detection
  34. Fermi-LAT gamma-ray observations of IceCube-220822A and detection of a new gamma-ray source, Fermi J1810.1+2154
  35. Fermi trigger No 682918137: Global MASTER-Net observations report
  36. GRB 220823A: Swift/BAT-GUANO detection of a short burst
  37. IceCube-220822A - IceCube observation of a high-energy neutrino candidate track-like event
  38. IceCube Alert 220822.85: Global MASTER-Net observations report
  39. GRB 220821A: Fermi GBM Final Real-time Localization
  40. Konus-Wind detection of GRB 220813A
  41. GRB 220813A: VLT optical observations and possible host galaxy
  42. GRB 220813A: Swift/UVOT Detection
  43. GRB 220810A: Further Swift-XRT observations
  44. GRB 220813A: Swift-XRT refined Analysis
  45. Swift GRB 220813A: Global MASTER-Net observations report
  46. GRB 220813A: Enhanced Swift-XRT position
  47. GRB 220813A: Swift detection of a burst with an optical counterpart
  48. GRB 220810A: Swift-XRT observations
  49. GRB 220719A: Detection by VZLUSAT-2
  50. Fermi trigger No 681998863: Global MASTER-Net observations report
  51. GRB 220810A: Swift ToO observations
  52. GRB 220810A: MeerLICHT detection of two afterglow candidates
  53. Fermi GBM trigger 681998863/220812505 is not a GRB
  54. Fermi trigger No 681890304: Global MASTER-Net observations report
  55. Fermi GBM trigger 681890304/220811249 is not a GRB
  56. Fermi GRB 220810A: Global MASTER-Net observations report
  57. GRB 220810A: Fermi GBM Final Real-time Localization
  58. GRB 220627A: MeerKAT radio observations
  59. GRB 220806A: Swift-BAT refined analysis
  60. Fermi trigger No 681719116: Global MASTER-Net observations report
  61. Fermi GBM trigger 681719116/220809267 is not a GRB
  62. Fermi trigger No 681633544: Global MASTER-Net observations report
  63. IceCube Astrotrack Bronze 136918_45252263.amon is likely background
  64. Fermi GBM trigger 681633544/220808277 is not a GRB
  65. IceCube Alert 220808.33: Global MASTER-Net observations report
  66. Fermi GBM trigger 681547990 / 220807287 is not a GRB
  67. GRB 220806A: Swift detection of a burst
  68. Swift GRB220806.76: Global MASTER-Net observations report
  69. GRB 220804A: Fermi GBM Final Localization
  70. Fermi trigger No 681271717: Global MASTER-Net observations report
  71. GRB 220803A: AstroSat CZTI detection
  72. Fermi trigger No 681212354: Global MASTER-Net observations report
  73. Konus-Wind detection of GRB 220730A (short)
  74. GRB 220730A: Swift-BAT refined analysis
  75. GRB 220730A: Fermi GBM detection
  76. GRB 220730A: Swift-XRT afterglow detection
  77. GRB 220730A: Swift/UVOT Upper Limits
  78. GRB 220730A: Swift-XRT observations
  79. GRB 220729A: AstroSat CZTI detection
  80. Swift GRB 220730A: Global MASTER-Net observations report
  81. GRB 220730A: Swift detection of a short hard burst
  82. Fermi trigger No 680782656: Global MASTER-Net observations report
  83. Fermi GRB 220728A: Global MASTER-Net observations report
  84. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-220728A
  85. GRB 220728A: Fermi GBM Final Real-time Localization
  86. GRB 220726A: Fermi GBM Final Real-time Localization
  87. Fermi trigger No 680421061: Global MASTER-Net observations report
  88. Fermi GRB 220724A: Global MASTER-Net observations report
  89. GRB 220724A: Fermi GBM Final Real-time Localization
  90. GRB 220715B: VIRT Optical Upper Limit
  91. Fermi GRB 220721A: Global MASTER-Net observations report
  92. GRB 220721A: Fermi GBM Final Real-time Localization
  93. Introducing new GCN Kafka broker and web site for transient alerts, https://gcn.nasa.gov
  94. Retraction: Fermi GBM trigger 679932336.585264/220719587 is not a GRB
  95. GRB 220715A: CALET Gamma-Ray Burst Monitor detection
  96. GRB 220711B: CALET Gamma-Ray Burst Monitor detection
  97. GRB 220719A: Fermi GBM Final Real-time Localization
  98. GRB 220715B: Swift-BAT refined analysis
  99. GRB220714B: UVOT detections
  100. GRB 220715B: Fermi GBM detection

Advanced

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