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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"

36404 results found.

  1. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  2. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  3. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  4. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  5. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  6. Fermi GRB 240702A: Global MASTER-Net observations report
  7. GRB 240702A: Fermi GBM Final Real-time Localization
  8. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  9. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  10. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  11. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  12. Fermi GRB 240629A: Global MASTER-Net observations report
  13. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  14. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  15. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  16. GRB 240629A: Fermi GBM Final Real-time Localization
  17. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  18. IPN triangulation of GRB 240619C
  19. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  20. GRB 240627A: NuSTAR Detection of the long GRB
  21. GRB 240615A: SAI CMO J- band observations
  22. GRB 240627A: AstroSat CZTI detection
  23. EP240626a: Montarrenti Observatory optical upper limit
  24. EP240626a: KAIT optical upper limit
  25. GRB 240624A: Swift-BAT refined analysis
  26. Konus-Wind detection of GRB 240619A
  27. Fermi GRB 240625B: Global MASTER-Net observations report
  28. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  29. GRB 240625B: Fermi GBM Final Real-time Localization
  30. GRB 240625A: Fermi GBM Observation
  31. GRB 240624B: GRBAlpha detection
  32. GRB 240625A: Fermi GBM Final Real-time Localization
  33. GRB240624A: Fermi GBM Observation
  34. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  35. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  36. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  37. Swift GRB 240624A: Global MASTER-Net observations report
  38. GRB240615A: Gemini-North observations of the BAT and XRT positions
  39. Fermi GRB 240624A: Global MASTER-Net observations report
  40. GRB 240624B: Fermi GBM Final Real-time Localization
  41. GRB240615A: Gemini-North observations of the BAT and XRT positions
  42. GRB 240624A: Fermi GBM Final Real-time Localization
  43. GRB 240619A: detection of a radio counterpart with AMI-LA
  44. GRB 240624A: Swift detection of a burst
  45. GRB 240619A: J-band detection with WINTER (duplicate submission of GCN 36739)
  46. GRB 240619A: J-band detection with WINTER
  47. EP240618a: NOT optical counterpart candidate
  48. GRB 240529A: JinShan optical observations
  49. IPN triangulation of GRB 240615A (short)
  50. GRB 240619A: GRBAlpha detection
  51. GRB 240619A: Swift-XRT probable afterglow detection
  52. GRB 240619A: Swift ToO observations
  53. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  54. GRB 240619C: NuSTAR automated detection of the GRB
  55. GRB 240619A: Fermi GBM Observation
  56. Fermi GBM Sub-Threshold Detection of GRB 240619C
  57. GRB 240619A: GOTO candidate optical afterglow
  58. EP240618a: Abastumani optical observationsEP240618a
  59. GRB 240615A: NOT optical observations
  60. GRB 240619C: AstroSat CZTI detection
  61. Fermi GRB 240619A: Global MASTER-Net observations report
  62. EP240617a: STEP/T80S optical limits
  63. GRB 240615A: possible transient detection from Wendelstein observations
  64. Fermi Gamma-ray Burst Monitor trigger 740474239/240619304 is not a GRB
  65. GRB 240619B: Fermi GBM Final Real-time Localization
  66. GRB240615A: 1.3m DFOT optical upper limit
  67. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  68. GRB 240619A: Fermi GBM Final Real-time Localization
  69. EP240617a: BOOTES-6/DPRT optical upper limit
  70. EP240617a is likely a GRB event
  71. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  72. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  73. GRB 240615A: J-band upper limits from WINTER
  74. GRB 240615A: Fermi GBM Observation
  75. GRB 240615A: Swift-XRT observations
  76. GRB 240615A: GECAM detection
  77. GRB 240615A: FLWO-1.2m optical upper limits
  78. Fermi GRB 240616A: Global MASTER-Net observations report
  79. Konus-Wind detection of GRB 240615A (short/hard)
  80. GRB 240615A: GOTO optical upper limits
  81. GRB 240616A: Fermi GBM Final Real-time Localization
  82. GRB 240615A: Swift ToO observations
  83. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  84. GRB 240615A: Fermi GBM Final Real-time Localization
  85. GRB 240603A: VZLUSAT-2 detection
  86. GRB 240612A: GRBAlpha detection
  87. GRB 240613A: Fermi GBM Final Real-time Localization
  88. Fermi GRB 240612B: Global MASTER-Net observations report
  89. Fermi GRB 240612A: Global MASTER-Net observations report
  90. GRB 240612B: Fermi GBM Final Real-time Localization
  91. GRB 240612A: Fermi GBM Final Real-time Localization
  92. GRB 240607A: GECAM detection of a bright long burst
  93. Fermi GRB 240611A: Global MASTER-Net observations report
  94. Konus-Wind detection of GRB 240607A
  95. GRB 240611A: Fermi GBM Final Real-time Localization
  96. GRB 240529A: LBT optical detection and late temporal decay
  97. GRB 240529A : MITSuME Akeno optical afterglow detection
  98. Fermi GRB 240610A: Global MASTER-Net observations report
  99. GRB 240610A: Fermi GBM Final Real-time Localization
  100. IPN triangulation of GRB 240607A

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