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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"

22195 results found.

  1. Fermi trigger No 701321709: Global MASTER-Net observations report
  2. GRB 230322B: Swift/UVOT Detection
  3. Konus-Wind detection of GRB 230309A
  4. Konus-Wind detection of GRB 230304B
  5. Swift GRB 230322B: Global MASTER-Net observations report
  6. Fermi trigger No 701071944: Global MASTER-Net observations report
  7. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  8. Fermi GRB 230320A: Global MASTER-Net observations report
  9. Fermi GRB 230321A: Global MASTER-Net observations report
  10. Fermi trigger No 701058254: Global MASTER-Net observations report
  11. Fermi trigger No 700976129: Global MASTER-Net observations report
  12. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  13. Fermi GRB 230316A: Global MASTER-Net observations report
  14. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  15. Fermi GRB 230314A: Global MASTER-Net observations report
  16. GRB 230307A: ATCA radio detection
  17. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  18. GRB 230307A: Swift/UVOT detection
  19. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230313A
  20. Fermi GRB 230313A: Global MASTER-Net observations report
  21. GRB 230307A: soft X-ray detection with LEIA
  22. GRB 230307A: Swift-XRT afterglow detection
  23. Swift GRB230311.85: Global MASTER-Net observations report
  24. Swift GRB230311.83: Global MASTER-Net observations report
  25. Swift GRB230311.81: Global MASTER-Net observations report
  26. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  27. Swift GRB230311.84: Global MASTER-Net observations report
  28. Swift GRB230311.82: Global MASTER-Net observations report
  29. Triggers 1159434, 1159435 and 1159437: Swift detection of Sco X-1 due to Star Tracker loss of lock
  30. Alert from the HAWC Burst Monitor HAWC-230311A
  31. TESS Detection of the Optical Afterglow of GRB230307A
  32. Trigger 1159327: Swift detection of SGR1806-20
  33. GRB 230307A: GECKO optical observations and detections of the afterglow
  34. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  35. Fermi GRB 230310A: Global MASTER-Net observations report
  36. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  37. GRB 230307A: Erratum of the GCN 33441
  38. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  39. GRB 230307A: Possible optical afterglow
  40. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  41. GRB 230217A: ATCA rapid-response radio detection
  42. GRB 230307A: Swift/BAT upper limits on the early afterglow
  43. GRB 230307A: Swift-XRT observations
  44. Fermi GRB 230307A: Global MASTER-Net observations report
  45. Konus-Wind detection of GRB 230307A
  46. Fermi GRB 230308A: Global MASTER-Net observations report
  47. GRB 230307A: Tiled Swift observations
  48. Fermi-LAT gamma-ray observations of IceCube-230306A
  49. GRB 230307A: GECAM detection of an extremely bright burst
  50. Fermi trigger No 699811746: Global MASTER-Net observations report
  51. IceCube Alert 230306.46: Global MASTER-Net observations report
  52. GRB 230228A: 6 GHz VLA radio upper limit
  53. GRB 230228A: Swift/UVOT Upper Limits
  54. Fermi GRB 230301B: Global MASTER-Net observations report
  55. Fermi trigger No 699294715: Global MASTER-Net observations report
  56. Fermi trigger No 699311646: Global MASTER-Net observations report
  57. GRB 230228A: Mondy optical upper limit
  58. Fermi GRB 230227A: Global MASTER-Net observations report
  59. Fermi trigger No 699029364: Global MASTER-Net observations report
  60. GRB 230217A: VLT/FORS2 optical observations and candidate counterpart
  61. GRB 230216A Mondy Observations
  62. GRB 230205A: VLA radio afterglow confirmation
  63. GRB 230217A: Swift/UVOT Upper Limits
  64. GRB 230216A: Swift/UVOT Upper Limits
  65. GRB 230217A: Continued Gemini Observations
  66. GRB 230217A: Swift-XRT afterglow detection
  67. Fermi-LAT gamma-ray observations of IceCube-230220A
  68. Fermi GRB 230220B: Global MASTER-Net observations report
  69. GRB 230217A: Gemini South optical upper limits
  70. GRB 230217A: 6 GHz VLA observations
  71. GRB 230217A: Gemini-South Optical Observation
  72. IceCube-230217A: BOOTES-4/MET Optical Observations
  73. Fermi-LAT gamma-ray observations of IceCube-230217A
  74. GRB 230217A: Swift-XRT observations
  75. Fermi trigger No 698427992: Global MASTER-Net observations report
  76. IceCube Alert 230217.87: Global MASTER-Net observations report
  77. GRB 230205A: Lowell Discovery Telescope Observations
  78. GRB 230204B: Lowell Discovery Telescope Observations
  79. Swift GRB 230216A: Global MASTER-Net observations report
  80. GRB 230216A: Zadko observatory - Gingin optical observations
  81. Fermi GRB 230215A: Global MASTER-Net observations report
  82. GRB 230204B: ATCA radio detection
  83. Fermi trigger No 697926015: Global MASTER-Net observations report
  84. Fermi trigger No 697904388: Global MASTER-Net observations report
  85. GRB 230209B: Swift/BAT-GUANO detection outside the coded FOV
  86. Fermi trigger No 697678542: Global MASTER-Net observations report
  87. Fermi GRB 230209B: Global MASTER-Net observations report
  88. GRB 230205A: 6 GHz VLA observations
  89. GRB 221009A: Continued Swift Observations
  90. GRB 230205A: possible host galaxy detection with the Schmidt - Asiago telescope
  91. GRB 230204B: MASTER early OT detection
  92. GRB 230207B: Swift/BAT-GUANO detection outside the coded FOV
  93. ZTF23aabmzlp/AT2023azs: Neil Gehrels Swift Observatory X-ray observations
  94. Fermi GRB 230207A: Global MASTER-Net observations report
  95. GRB 230204B: Swift/UVOT Upper Limits
  96. Fermi trigger No 697403223: Global MASTER-Net observations report
  97. Fermi trigger No 697396830: Global MASTER-Net observations report
  98. GRB 230205A: Swift/UVOT Upper Limits
  99. GRB 230204B: Swift-XRT afterglow detection
  100. GRB 230205A: OHP/T193 optical observations

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