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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"

36409 results found.

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

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