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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"

37768 results found.

  1. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  2. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  3. IceCube-260115A - IceCube observation of a high-energy neutrino candidate track-like event
  4. GRB 260115A: BALROG localization (Fermi Trigger 790192010 / GRB 260115741)
  5. Fermi GRB 260115A: Global MASTER-Net observations report
  6. GRB 260115A: Fermi GBM Final Real-time Localization
  7. GRB260114A: STEP/T80S optical limits
  8. GRB 251222A: radio detection with the VLA
  9. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  10. Konus-Wind detection of GRB 260114A
  11. GRB 260114A: Swift-XRT refined Analysis
  12. GRB 260114A: 6 GHz VLA observations
  13. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  14. GRB 260114A : MITSuME Akeno optical upper limits
  15. GRB 260114A: COLIBRÍ optical upper limits
  16. GRB 260114A: TNG NIR upper limit
  17. GRB 260114A: NOT optical observations
  18. Konus-Wind detection of GRB 251230A / EP251230a
  19. GRB 260114A: SVOM/GRM observation of a short burst
  20. Swift GRB 260114A: Global MASTER-Net observations report
  21. GRB 260114A: GECAM-B observation of a short burst
  22. GRB 260114A: Mondy optical observations
  23. GRB 260114A: Fermi GBM observation
  24. GRB 260112B: GECAM-B observation
  25. GRB 260114A: GMG Optical Observation
  26. Fermi-LAT Gamma-ray Observations of IceCube-260111A
  27. GRB 260114A: Swift detection of a short burst
  28. GRB 260114A: Fermi GBM Final Real-time Localization
  29. Konus-Wind detection of GRB 260101A
  30. GRB 260111A: Swift-XRT observations
  31. Swift Trigger 1439093: is probably not GRB 260113A
  32. GRB 260111A: COLIBRÍ optical afterglow candidate
  33. GRB 260111A: GECAM-B observation of a burst
  34. GRB 260111A: Fermi GBM Observation
  35. Swift Trigger 1434591 is not a GRB
  36. GRB 260111A: GOTO optical upper limits
  37. GRB 260112B: Fermi GBM Final Real-time Localization
  38. GRB 260111A: Swift ToO observations
  39. GRB 251230A: Mondy Optical Observations
  40. GRB 260111A: Swift/BAT-GUANO arcminute localization of a burst
  41. GRB 260112A: Fermi GBM Final Real-time Localization
  42. IceCube-260111A - IceCube observation of a high-energy neutrino candidate track-like event
  43. Fermi GRB 260111A: Global MASTER-Net observations report
  44. GRB 260111A: Fermi GBM Final Real-time Localization
  45. EP260110a: KAIT optical upper limit
  46. GRB 260109C: LCO optical upper limits
  47. GRB 260109C: Kilonova-Catcher optical upper limit
  48. EP260105b / GRB 260105C : Fermi-GBM Sub-Threshold Detection
  49. Swift Trigger 1434591: possible GRB 260109C
  50. GRB 260109B: Fermi GBM Final Real-time Localization
  51. GRB 260102A: Swift-XRT afterglow detection
  52. GRB 260109A: Fermi GBM Final Real-time Localization
  53. GRB 260104A: Swift-BAT refined analysis
  54. GRB 260101A: Swift-BAT refined analysis
  55. Swift GRB 251230A: Global MASTER-Net OT detection
  56. Fermi GRB 260107A: Global MASTER-Net observations report
  57. GRB 260102A: AbAO optical observations
  58. GRB 260107A: Fermi GBM Final Real-time Localization
  59. Fermi GRB 260105A: Global MASTER-Net observations report
  60. GRB 260105B: Fermi GBM Detection
  61. GRB 260105B: BALROG localization (Fermi Trigger 789348101 / GRB 260105973)
  62. GRB 260105A: SVOM/GRM observation
  63. GRB 260105B: SVOM/GRM observation
  64. Fermi GRB 260105B: Global MASTER-Net observations report
  65. GRB 260105B: Fermi GBM Final Real-time Localization
  66. GRB 260105A: Fermi GBM Final Real-time Localization
  67. GRB 260101A: COLIBRÍ optical upper limits
  68. GRB 260103A: Insight-HXMT/HE detection
  69. GRB 260104A: COLIBRÍ optical upper limits
  70. GRB 260104C: Fermi GBM Final Real-time Localization
  71. Fermi GRB 260104B: Global MASTER-Net observations report
  72. Swift GRB 260104A: Global MASTER-Net observations report
  73. GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
  74. GRB 260104A: Swift-XRT refined Analysis
  75. GRB 260104A: Enhanced Swift-XRT position
  76. GRB 260101A: Swift/UVOT Detection
  77. GRB 260103A: GECAM-B observation of a burst
  78. GRB 260104B: Fermi GBM Final Localization
  79. GRB 260104A: Swift detection of a burst
  80. GRB 260103A: SVOM/GRM observation of a possible GRB
  81. Fermi-LAT Gamma-ray Observations of IceCube-251225A
  82. GRB 260101A: COLIBRÍ optical observations
  83. GRB 260102B: Fermi GBM Final Real-time Localization
  84. Fermi GBM Sub-Threshold Detection of GRB 260102A
  85. GRB 260102A: EP-FXT follow-up observation
  86. GRB 260102A: LCO optical upper limits
  87. GRB 260102A: Swift-XRT observations
  88. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  89. Fermi Gamma-ray Burst Monitor trigger 789047602/260102495 is not a GRB
  90. GRB 251230A / EP251230a: GECAM-B detection
  91. GRB 260102A: SVOM/VT optical counterpart
  92. GRB 251230A / EP251230a: Insight-HXMT/HE detection
  93. GRB 260102A: Swift ToO observations
  94. GRB 260101A: Fermi GBM Observation
  95. GRB 260102A: SVOM detection of a burst
  96. GRB 260101A: GECAM-B detection
  97. GRB 260101A: NOT spectroscopic observations
  98. GRB 260101A: SVOM/GRM observation
  99. GRB 260101A: Swift-XRT refined Analysis
  100. Swift GRB 260101A: Global MASTER-Net observations report

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