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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

11856 results found.

  1. Fermi-LAT Gamma-ray Observations of IceCube-201120A
  2. IceCube-201120A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  3. IceCube-201120A: Swift-XRT non-detection of 4FGL J2028.6+4110e
  4. GRB 201015A radio afterglow with e-MERLIN
  5. Fermi GRB 201120B: Global MASTER-Net observations report
  6. GRB 201120B: Fermi GBM Final Localization
  7. GRB 201120A: Fermi GBM Final Localization
  8. IceCube-201120A: Upper limits from Fermi-GBM Observations
  9. Fermi trigger No 627557935: Global MASTER-Net observations report
  10. Baksan Neutrino Observatory Alert 201120.43: Global MASTER-Net observations report
  11. IceCube Alert 201120.41: Global MASTER-Net observations report
  12. IceCube-201120A: IceCube observation of a high-energy neutrino candidate event
  13. ZTF20acozryr/AT2020yxz (GRB 201103B): SAO RAS optical observations
  14. IceCube 201114A: Swift followup of Fermi J0703.5+0505
  15. Konus-Wind detection of GRB 201116A
  16. Fermi-LAT Gamma-ray Observations of IceCube-201114A
  17. GRB 201116A: Swift-XRT afterglow detection
  18. Fermi trigger No 627198169: Global MASTER-Net observations report
  19. GRB 201116A: Fermi-LAT detection
  20. Fermi-LAT Gamma-ray Observations of IceCube-201115A
  21. Swift XRT observations of the Fermi-LAT source 4FGL J0658.6+0636, positionally consistent with the IceCube high-energy neutrino alert
  22. IceCube GCN alert 134701_49508272.amon retraction
  23. IceCube-201115A: IceCube observation of a high-energy neutrino candidate event
  24. IceCube-201114A - IceCube observation of a high-energy neutrino candidate event
  25. Fermi-LAT Gamma-ray Observations of NuEm-201107A
  26. Konus-Wind observation of GRB 201109A
  27. ZTF20acozryr (GRB 201103B): GROWTH-India Telescope optical observations
  28. Konus-Wind observation of GRB 201103B
  29. Konus-Wind detection of GRB 201105A
  30. ZTF20acozryr/AT2020yxz (GRB 201103B): Assy optical observations
  31. GRB 201104B: Swift-XRT refined Analysis
  32. ZTF20acozryr/AT2020yxz: Zwicky Transient Facility discovery of a fast optical transient with no associated GRB
  33. GRB 201103B: AGILE detection
  34. GRB 201104A: AGILE/MCAL detection
  35. GRB 201104A: Fermi-LAT detection
  36. GRB 201104B: Swift/UVOT Detection
  37. Fermi GRB 201104A: Global MASTER-Net observations report
  38. Fermi GRB 201103A: Global MASTER-Net observations report
  39. Swift GRB 201031A: Global MASTER-Net observations report
  40. Fermi GRB 201031B: Global MASTER-Net observations report
  41. IceCube 201021A: Swift follow-up of Fermi J1725.5+1312
  42. Swift GRB 201029A: Global MASTER-Net observations report
  43. GRB 201029A: Fermi GBM detection
  44. GRB 201029A: Swift-XRT refined Analysis
  45. GRB 201029A: BOOTES-1 optical upper limit
  46. GRB 201029A: FRAM-ORM optical limit
  47. Fermi trigger No 625695596: Global MASTER-Net observations report
  48. GRB 201029A: Swift detection of a burst
  49. GRB 201027A: Swift-BAT refined analysis
  50. GRB 201027A: Swift-XRT refined Analysis
  51. Baksan Neutrino Observatory Alert 201027.41: Global MASTER-Net observations report
  52. GRB 201026A: FRAM-ORM optical detection limit
  53. GRB 201027A: Swift detection of a burst
  54. GRB201024A: rebrightening after initial steep decline
  55. GRB 201024A: Swift-XRT refined Analysis
  56. GRB 201024A: FRAM-ORM afterglow detection
  57. GRB 201024A: MASTER correction to GCN 28760
  58. GRB 201024A: Swift detection of a burst with an optical afterglow
  59. Swift GRB201024A: Global MASTER-Net OT detection
  60. Swift GRB201024.12: Global MASTER-Net observations report
  61. IceCube-201021A: No significant detection in HAWC
  62. GRB 201021C: Swift-BAT refined analysis
  63. GRB 201021C: Swift-XRT refined Analysis
  64. Baksan Neutrino Observatory Alert 201022.66: Global MASTER-Net observations report
  65. Fermi-LAT Gamma-ray Observations of IceCube-201021A and detection of a new gamma-ray source, Fermi J1725.5+1312
  66. GRB 201021C: Fermi GBM detection
  67. IceCube-201021A: Upper limits from a search for additional neutrino events in IceCube
  68. GRB 201021C: Swift/UVOT Detection
  69. Konus-Wind detection of GRB 201020A
  70. GRB 201020A: VIRT optical observations
  71. GRB 201021C: MASTER optical synchronously observation
  72. Swift GRB201021.85: Global MASTER-Net observations report
  73. GRB 201021C: Swift detection of a burst with an optical counterpart
  74. MAXI GRB201021.68: Global MASTER-Net observations report
  75. GRB 201021B MAXI/GSC detection
  76. GRB 201020B: Mondy optical observations
  77. Swift-XRT observations of IceCube 201021A
  78. Konus-Wind detection of GRB 201020B
  79. GRB 201015A: SAO RAS optical observations
  80. GRB 201020A: Redshift from GTC/OSIRIS
  81. GRB 201020B: Fermi-LAT detection
  82. IceCube-201021A: IceCube observation of a high-energy neutrino candidate event
  83. GRB 201020B: AGILE detection
  84. GRB 201020A: DOAO optical afterglow observations
  85. GRB 201020B: Fermi GBM detection
  86. GRB 201020A: CrAO/ZTSH optical observations
  87. GRB 201020A: Swift-XRT refined Analysis
  88. GRB 201020A: Fermi GBM observation
  89. Fermi GRB 201020B: Global MASTER-Net observations report
  90. GRB 201020A: Assy optical observations
  91. GRB 201020B: Fermi GBM Final Real-time Localization
  92. GRB 201020A: Nanshan/NEXT optical observations
  93. Swift GRB 201020A: Global MASTER-Net observations report
  94. GRB 201014A: SAO RAS optical observations
  95. GRB 201020A: MITSuME Akeno optical observation
  96. GRB 201020A: Swift detection of a burst with an optical counterpart.
  97. GRB 201017A iTelescope observation
  98. GRB 201017A: SAO RAS optical observations
  99. GRB 201017A: Swift-BAT refined analysis
  100. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection

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