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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"

38151 results found.

  1. EP260116a: Global MASTER-Net observations report
  2. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  3. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  4. IceCube Alert 260115.73: Global MASTER-Net observations report
  5. GRB 260115A: BALROG localization (Fermi Trigger 790192010 / GRB 260115741)
  6. Fermi GRB 260115A: Global MASTER-Net observations report
  7. GRB 260115A: Fermi GBM Final Real-time Localization
  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. GRB 260114A: Swift detection of a short burst
  27. GRB 260114A: Fermi GBM Final Real-time Localization
  28. Swift GRB260113.43: Global MASTER-Net observations report
  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 Alert 260111A: Global MASTER-Net observations report
  43. EP260110a: Global MASTER-Net observations report
  44. Fermi GRB 260111A: Global MASTER-Net observations report
  45. GRB 260111A: Fermi GBM Final Real-time Localization
  46. EP260110a: KAIT optical upper limit
  47. GRB 260109C: LCO optical upper limits
  48. GRB 260109C: Kilonova-Catcher optical upper limit
  49. EP260105b / GRB 260105C : Fermi-GBM Sub-Threshold Detection
  50. Swift Trigger 1434591: possible GRB 260109C
  51. GRB 260109B: Fermi GBM Final Real-time Localization
  52. GRB 260102A: Swift-XRT afterglow detection
  53. GRB 260109A: Fermi GBM Final Real-time Localization
  54. GRB 260104A: Swift-BAT refined analysis
  55. GRB 260101A: Swift-BAT refined analysis
  56. Swift GRB 251230A: Global MASTER-Net OT detection
  57. Fermi GRB 260107A: Global MASTER-Net observations report
  58. GRB 260102A: AbAO optical observations
  59. GRB 260107A: Fermi GBM Final Real-time Localization
  60. Fermi GRB 260105A: Global MASTER-Net observations report
  61. GRB 260105B: Fermi GBM Detection
  62. GRB 260105B: BALROG localization (Fermi Trigger 789348101 / GRB 260105973)
  63. GRB 260105A: SVOM/GRM observation
  64. GRB 260105B: SVOM/GRM observation
  65. Fermi GRB 260105B: Global MASTER-Net observations report
  66. GRB 260105B: Fermi GBM Final Real-time Localization
  67. GRB 260105A: Fermi GBM Final Real-time Localization
  68. EP260104a: Global MASTER-Net observations report
  69. GRB 260101A: COLIBRÍ optical upper limits
  70. EP260105a: Global MASTER-Net observations report
  71. GRB 260103A: Insight-HXMT/HE detection
  72. GRB 260104A: COLIBRÍ optical upper limits
  73. GRB 260104C: Fermi GBM Final Real-time Localization
  74. Fermi GRB 260104B: Global MASTER-Net observations report
  75. Swift GRB 260104A: Global MASTER-Net observations report
  76. GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
  77. GRB 260104A: Swift-XRT refined Analysis
  78. GRB 260104A: Enhanced Swift-XRT position
  79. GRB 260101A: Swift/UVOT Detection
  80. GRB 260103A: GECAM-B observation of a burst
  81. GRB 260104B: Fermi GBM Final Localization
  82. GRB 260104A: Swift detection of a burst
  83. GRB 260103A: SVOM/GRM observation of a possible GRB
  84. GRB 260101A: COLIBRÍ optical observations
  85. SVOM GRB260103.08: Global MASTER-Net observations report
  86. GRB 260102B: Fermi GBM Final Real-time Localization
  87. SVOM GRB260102A: Global MASTER-Net observations report
  88. Fermi GBM Sub-Threshold Detection of GRB 260102A
  89. GRB 260102A: EP-FXT follow-up observation
  90. EP260101a: Global MASTER-Net observations report
  91. GRB 260102A: LCO optical upper limits
  92. GRB 260102A: Swift-XRT observations
  93. GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
  94. Fermi Gamma-ray Burst Monitor trigger 789047602/260102495 is not a GRB
  95. GRB 251230A / EP251230a: GECAM-B detection
  96. GRB 260102A: SVOM/VT optical counterpart
  97. GRB 251230A / EP251230a: Insight-HXMT/HE detection
  98. GRB 260102A: Swift ToO observations
  99. GRB 260101A: Fermi GBM Observation
  100. GRB 260102A: SVOM detection of a burst

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