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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"

37674 results found.

  1. GRB 240629A: Fermi GBM Final Real-time Localization
  2. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  3. Fermi trigger No 741296200: Global MASTER-Net observations report
  4. Fermi trigger No 741251380: Global MASTER-Net observations report
  5. IPN triangulation of GRB 240619C
  6. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  7. GRB 240627A: NuSTAR Detection of the long GRB
  8. GRB 240615A: SAI CMO J- band observations
  9. GRB 240627A: AstroSat CZTI detection
  10. Fermi trigger No 741211696: Global MASTER-Net observations report
  11. EP240626a: Montarrenti Observatory optical upper limit
  12. EP240626a: KAIT optical upper limit
  13. GRB 240624A: Swift-BAT refined analysis
  14. Konus-Wind detection of GRB 240619A
  15. Fermi GRB 240625B: Global MASTER-Net observations report
  16. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 240625B: Fermi GBM Final Real-time Localization
  18. GRB 240625A: Fermi GBM Observation
  19. GRB 240624B: GRBAlpha detection
  20. GRB 240625A: Fermi GBM Final Real-time Localization
  21. GRB240624A: Fermi GBM Observation
  22. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  23. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  24. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  25. Swift GRB 240624A: Global MASTER-Net observations report
  26. GRB240615A: Gemini-North observations of the BAT and XRT positions
  27. Fermi GRB 240624A: Global MASTER-Net observations report
  28. GRB 240624B: Fermi GBM Final Real-time Localization
  29. Fermi trigger No 740949590: Global MASTER-Net observations report
  30. GRB240615A: Gemini-North observations of the BAT and XRT positions
  31. GRB 240624A: Fermi GBM Final Real-time Localization
  32. GRB 240619A: detection of a radio counterpart with AMI-LA
  33. GRB 240624A: Swift detection of a burst
  34. GRB 240619A: J-band detection with WINTER (duplicate submission of GCN 36739)
  35. GRB 240619A: J-band detection with WINTER
  36. Fermi trigger No 740744838: Global MASTER-Net observations report
  37. EP240618a: NOT optical counterpart candidate
  38. GRB 240529A: JinShan optical observations
  39. IPN triangulation of GRB 240615A (short)
  40. X-ray transient EP240618a: Fermi/GBM non-detection
  41. GRB 240619A: GRBAlpha detection
  42. EP240617a: tentative Swift/XRT detection of the afterglow
  43. GRB 240619A: Swift-XRT probable afterglow detection
  44. GRB 240619A: Swift ToO observations
  45. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  46. GRB 240619C: NuSTAR automated detection of the GRB
  47. GRB 240619A: Fermi GBM Observation
  48. Fermi GBM Sub-Threshold Detection of GRB 240619C
  49. GRB 240619A: GOTO candidate optical afterglow
  50. EP240618a: Abastumani optical observationsEP240618a
  51. GRB 240615A: NOT optical observations
  52. GRB 240619C: AstroSat CZTI detection
  53. Fermi trigger No 740474239: Global MASTER-Net observations report
  54. Fermi GRB 240619A: Global MASTER-Net observations report
  55. GRB 240615A: possible transient detection from Wendelstein observations
  56. Fermi Gamma-ray Burst Monitor trigger 740474239/240619304 is not a GRB
  57. GRB 240619B: Fermi GBM Final Real-time Localization
  58. Fermi trigger No 740430582: Global MASTER-Net observations report
  59. GRB240615A: 1.3m DFOT optical upper limit
  60. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  61. GRB 240619A: Fermi GBM Final Real-time Localization
  62. EP240617a: BOOTES-6/DPRT optical upper limit
  63. EP240617a is likely a GRB event
  64. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  65. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  66. GRB 240615A: J-band upper limits from WINTER
  67. GRB 240615A: Fermi GBM Observation
  68. GRB 240615A: Swift-XRT observations
  69. GRB 240615A: GECAM detection
  70. GRB 240615A: FLWO-1.2m optical upper limits
  71. Fermi trigger No 740221779: Global MASTER-Net observations report
  72. Fermi GRB 240616A: Global MASTER-Net observations report
  73. Konus-Wind detection of GRB 240615A (short/hard)
  74. GRB 240615A: GOTO optical upper limits
  75. Fermi trigger No 740166710: Global MASTER-Net observations report
  76. GRB 240616A: Fermi GBM Final Real-time Localization
  77. GRB 240615A: Swift ToO observations
  78. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  79. GRB 240615A: Fermi GBM Final Real-time Localization
  80. GRB 240603A: VZLUSAT-2 detection
  81. GRB 240612A: GRBAlpha detection
  82. GRB 240613A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 240612B: Global MASTER-Net observations report
  84. Fermi GRB 240612A: Global MASTER-Net observations report
  85. GRB 240612B: Fermi GBM Final Real-time Localization
  86. GRB 240612A: Fermi GBM Final Real-time Localization
  87. GRB 240607A: GECAM detection of a bright long burst
  88. Fermi GRB 240611A: Global MASTER-Net observations report
  89. Konus-Wind detection of GRB 240607A
  90. GRB 240611A: Fermi GBM Final Real-time Localization
  91. GRB 240529A: LBT optical detection and late temporal decay
  92. GRB 240529A : MITSuME Akeno optical afterglow detection
  93. Fermi GRB 240610A: Global MASTER-Net observations report
  94. GRB 240610A: Fermi GBM Final Real-time Localization
  95. IPN triangulation of GRB 240607A
  96. Fermi Gamma-ray Burst Monitor trigger 739632045/240609556 is not a GRB
  97. Fermi trigger No 739632045: Global MASTER-Net observations report
  98. Fermi GRB 240608A: Global MASTER-Net observations report
  99. Konus-Wind detection of GRB 240606B
  100. Fermi trigger No 739506569: Global MASTER-Net observations report

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