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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"

36192 results found.

  1. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  2. GRB 240627A: NuSTAR Detection of the long GRB
  3. GRB 240615A: SAI CMO J- band observations
  4. GRB 240627A: AstroSat CZTI detection
  5. EP240626a: Montarrenti Observatory optical upper limit
  6. EP240626a: KAIT optical upper limit
  7. GRB 240624A: Swift-BAT refined analysis
  8. Konus-Wind detection of GRB 240619A
  9. Fermi GRB 240625B: Global MASTER-Net observations report
  10. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  11. GRB 240625B: Fermi GBM Final Real-time Localization
  12. GRB 240625A: Fermi GBM Observation
  13. GRB 240624B: GRBAlpha detection
  14. GRB 240625A: Fermi GBM Final Real-time Localization
  15. GRB240624A: Fermi GBM Observation
  16. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  18. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  19. Swift GRB 240624A: Global MASTER-Net observations report
  20. GRB240615A: Gemini-North observations of the BAT and XRT positions
  21. Fermi GRB 240624A: Global MASTER-Net observations report
  22. GRB 240624B: Fermi GBM Final Real-time Localization
  23. GRB240615A: Gemini-North observations of the BAT and XRT positions
  24. GRB 240624A: Fermi GBM Final Real-time Localization
  25. GRB 240619A: detection of a radio counterpart with AMI-LA
  26. GRB 240624A: Swift detection of a burst
  27. GRB 240619A: J-band detection with WINTER (duplicate submission of GCN 36739)
  28. GRB 240619A: J-band detection with WINTER
  29. EP240618a: NOT optical counterpart candidate
  30. GRB 240529A: JinShan optical observations
  31. IPN triangulation of GRB 240615A (short)
  32. GRB 240619A: GRBAlpha detection
  33. GRB 240619A: Swift-XRT probable afterglow detection
  34. GRB 240619A: Swift ToO observations
  35. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  36. GRB 240619C: NuSTAR automated detection of the GRB
  37. GRB 240619A: Fermi GBM Observation
  38. Fermi GBM Sub-Threshold Detection of GRB 240619C
  39. GRB 240619A: GOTO candidate optical afterglow
  40. EP240618a: Abastumani optical observationsEP240618a
  41. GRB 240615A: NOT optical observations
  42. GRB 240619C: AstroSat CZTI detection
  43. Fermi GRB 240619A: Global MASTER-Net observations report
  44. GRB 240615A: possible transient detection from Wendelstein observations
  45. Fermi Gamma-ray Burst Monitor trigger 740474239/240619304 is not a GRB
  46. GRB 240619B: Fermi GBM Final Real-time Localization
  47. GRB240615A: 1.3m DFOT optical upper limit
  48. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  49. GRB 240619A: Fermi GBM Final Real-time Localization
  50. EP240617a: BOOTES-6/DPRT optical upper limit
  51. EP240617a is likely a GRB event
  52. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  53. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  54. GRB 240615A: J-band upper limits from WINTER
  55. GRB 240615A: Fermi GBM Observation
  56. GRB 240615A: Swift-XRT observations
  57. GRB 240615A: GECAM detection
  58. GRB 240615A: FLWO-1.2m optical upper limits
  59. Fermi GRB 240616A: Global MASTER-Net observations report
  60. Konus-Wind detection of GRB 240615A (short/hard)
  61. GRB 240615A: GOTO optical upper limits
  62. GRB 240616A: Fermi GBM Final Real-time Localization
  63. GRB 240615A: Swift ToO observations
  64. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  65. GRB 240615A: Fermi GBM Final Real-time Localization
  66. GRB 240603A: VZLUSAT-2 detection
  67. GRB 240612A: GRBAlpha detection
  68. GRB 240613A: Fermi GBM Final Real-time Localization
  69. Fermi GRB 240612B: Global MASTER-Net observations report
  70. Fermi GRB 240612A: Global MASTER-Net observations report
  71. GRB 240612B: Fermi GBM Final Real-time Localization
  72. GRB 240612A: Fermi GBM Final Real-time Localization
  73. GRB 240607A: GECAM detection of a bright long burst
  74. Fermi GRB 240611A: Global MASTER-Net observations report
  75. Konus-Wind detection of GRB 240607A
  76. GRB 240611A: Fermi GBM Final Real-time Localization
  77. GRB 240529A: LBT optical detection and late temporal decay
  78. GRB 240529A : MITSuME Akeno optical afterglow detection
  79. Fermi GRB 240610A: Global MASTER-Net observations report
  80. GRB 240610A: Fermi GBM Final Real-time Localization
  81. IPN triangulation of GRB 240607A
  82. Fermi Gamma-ray Burst Monitor trigger 739632045/240609556 is not a GRB
  83. Fermi GRB 240608A: Global MASTER-Net observations report
  84. Konus-Wind detection of GRB 240606B
  85. GRB 240608A: Fermi GBM Final Real-time Localization
  86. Fermi GRB 240607A: Global MASTER-Net observations report
  87. GRB 240529A: NOEMA detection
  88. GRB 240607A: Fermi GBM Observation
  89. GRB 240606B: Fermi GBM Observation
  90. Swift Trigger 1235109: consistent with noise and not astrophysical
  91. GRB 240607A: AstroSat CZTI detection of bright long burst
  92. GRB 240607A: Fermi GBM detection of a very bright burst
  93. GRB 240529A: radio detection with AMI-LA
  94. GRB 240607A: BALROG localization (Fermi Trigger 739450879 / GRB 240607459)
  95. GRB 240607A: Fermi GBM Final Real-time Localization
  96. GRB 240606B: GECAM-B detection a long burst
  97. GRB 240606B: Swift-XRT afterglow detection
  98. GRB 240606B: Swift ToO observations
  99. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  100. Konus-Wind detection of GRB 240603A

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