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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"

39408 results found.

  1. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  2. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  3. GRB 221009A: Swift detected transient may be GRB
  4. Swift GRB221009.59: Global MASTER-Net OT detection
  5. GRB 221008A: Swift-XRT observations
  6. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  7. GRB 221008A: Tiled Swift observations
  8. GRB 221008A: MAXI/GSC detection
  9. GRB 220915A: Detection by GRBAlpha
  10. GRB 221006A: Swift-XRT observations
  11. GRB 221006A: Tiled Swift observations
  12. GRB 221006A: MAXI/GSC detection
  13. GRB 220930A: MITSuME Akeno optical upper limits
  14. GRB 220912A: Detection by VZLUSAT-2
  15. Fermi trigger No 686588176: Global MASTER-Net observations report
  16. GRB220927A: Detection by GRBAlpha
  17. Fermi GBM trigger 686565116/221004355 is not a GRB
  18. Fermi GBM trigger 686435254/221002852 is not a GRB
  19. Fermi GBM trigger 686350260/221001869 is not a GRB
  20. GRB 220921A: ATCA detection of radio counterpart
  21. GRB 220930A: AbAO Optical Upper Limit
  22. Fermi trigger No 686403226: Global MASTER-Net observations report
  23. Fermi trigger No 686350260: Global MASTER-Net observations report
  24. Konus-Wind detection of GRB 220930A
  25. GRB 220930A: AstroSat CZTI detection
  26. GRB 220930A: Swift-BAT refined analysis
  27. GRB 220930A: Swift-XRT refined Analysis
  28. GRB 220930A: LCOGT Optical Upper Limits
  29. GRB 220930A: Swift/UVOT Upper Limits
  30. GRB 220930A: Enhanced Swift-XRT position
  31. Swift GRB 220930A: Global MASTER-Net observations report
  32. GRB 220930A: BOOTES-5/JGT early optical upper limit
  33. GRB 220930A: Prompt enhanced Swift-XRT position
  34. GRB 220930A: COATLI Upper Limits
  35. GRB 220930A: Swift detection of a burst
  36. Fermi-LAT gamma-ray observations of IceCube-220928A
  37. Konus-Wind detection of GRB 220927A
  38. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  39. Fermi GRB 220927A: Global MASTER-Net observations report
  40. IPN triangulation of GRB 220927A (long)
  41. GRB 220921A: LCOGT Optical Observations
  42. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  43. GRB 220927A: Fermi GBM Final Localization
  44. GRB 220924A: Fermi GBM detection
  45. Integral GRB220926.44: Global MASTER-Net observations report
  46. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  47. Swift Trigger 1125354 (GRB 220926A) is not a GRB
  48. Swift GRB220926.34: Global MASTER-Net observations report
  49. Swift GRB 220926A: Global MASTER-Net observations report
  50. Analysis of long GRB 220926B detected by INTEGRAL
  51. GRB 220926B
  52. GRB 220926A: Swift detection of a burst
  53. Fermi GRB 220925A: Global MASTER-Net observations report
  54. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  55. GRB 220921A: further MeerLICHT observations
  56. GRB 220925A: Fermi GBM Final Real-time Localization
  57. Fermi trigger No 685748699: Global MASTER-Net observations report
  58. GRB 220924A: Fermi GBM Final Real-time Localization
  59. Swift GRB220923.47: Global MASTER-Net observations report
  60. GRB 220921A: ALMA detection
  61. GRB 220921A: DDOTI Detection of the Afterglow
  62. Konus-Wind detection of GRB 220921A
  63. GRB 220921A: Fermi GBM detection
  64. GRB 220921A: MeerLICHT afterglow observations
  65. GRB 220921A: Swift-XRT Observations
  66. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  67. LAT GRB220921.46: Global MASTER-Net observations report
  68. GRB 220921A: Fermi-LAT detection
  69. GRB 220921A: Tiled Swift observations
  70. Fermi trigger No 685452089: Global MASTER-Net observations report
  71. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  72. IceCube Alert 220918.53: Global MASTER-Net observations report
  73. IceCube-220918A - IceCube observation of a high-energy neutrino candidate track-like event
  74. Fermi trigger No 684894705: Global MASTER-Net observations report
  75. Improved IPN error box for GRB 220910A
  76. Fermi trigger No 684927323: Global MASTER-Net observations report
  77. Fermi trigger No 684911625: Global MASTER-Net observations report
  78. GRB 220909A: Fermi GBM observation
  79. Konus-Wind detection of GRB 220910A
  80. GRB 220910B: Fermi GBM Final Localization
  81. Fermi trigger No 684716840: Global MASTER-Net observations report
  82. Fermi GRB 220912A: Global MASTER-Net observations report
  83. GRB 220910A: Fermi GBM observation
  84. IPN triangulation of GRB 220910A (bright/long)
  85. GRB 220912A: AstroSat CZTI detection
  86. GRB 220831A: DECam optical counterpart follow-up
  87. GRB 220909A: Swift-XRT observations
  88. GRB 220912A: Fermi GBM Final Real-time Localization
  89. IPN triangulation of GRB 220905A
  90. GRB 220909A: Swift ToO observations
  91. GRB 220909A: Swift/BAT-GUANO candidate arcminute localization
  92. GRB 220831A: Gemini-South Infrared Observations
  93. GRB 220910A: AstroSat CZTI detection
  94. GRB 220910A: AGILE detection
  95. GRB 220909A: Fermi GBM Final Real-time Localization
  96. GRB 220907A: Swift-BAT refined analysis
  97. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  98. IPN triangulation of GRB 220903A (long)
  99. GRB 220907A: Fermi GBM observation
  100. GRB 220907A: Nanshan/NEXT optical upper limits

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