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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. GRB 210104A: Assy continued optical observations
  2. Fermi GRB 210105A: Global MASTER-Net observations report
  3. GRB 210104A: Swift-XRT refined Analysis
  4. Konus-Wind detection of GRB 210104A
  5. GRB 210104B: Assy optical upper limit
  6. GRB 210104A: Swift/UVOT Detection
  7. Swift GRB210104.88: Global MASTER-Net observations report
  8. GRB 210102B: Assy optical observations
  9. Fermi GRB 210104A: Global MASTER-Net observations report
  10. GRB 210104A: Assy optical observations
  11. Fermi GRB 210102C: Global MASTER-Net observations report
  12. GRB 210102C: Fermi GBM detection
  13. GRB 210102C: Swift detection of a burst
  14. GRB 210102B: MAXI/GSC detection
  15. Fermi GRB 210101A: Global MASTER-Net observations report
  16. Swift GRB210102.01: Global MASTER-Net observations report
  17. Fermi trigger No 631226368: Global MASTER-Net observations report
  18. Fermi trigger No 631119348: Global MASTER-Net observations report
  19. Fermi trigger No 631113166: Global MASTER-Net observations report
  20. Fermi trigger No 631118376: Global MASTER-Net observations report
  21. Fermi trigger No 631104264: Global MASTER-Net observations report
  22. GRB 201216C: TSHAO, Terskol, Mondy optical upper limits
  23. Baksan Neutrino Observatory Alert 201230.40: Global MASTER-Net observations report
  24. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  25. GRB 201229A: Swift-XRT refined Analysis
  26. Konus-Wind observation of GRB 201227A
  27. GRB 201229B: BALROG localization (Fermi Trigger 630948017 / GRB 201229639)
  28. GRB 201229B: Fermi GBM Final Real-time Localization
  29. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  30. GRB 201020B: Assy, Koshka, Mondy and Maidanak optical observations
  31. ZTF20acozryr/AT2020yxz (GRB 201103B): Maidanak optical observations
  32. Fermi trigger No 630681391: Global MASTER-Net observations report
  33. GRB 201223A: Swift-XRT refined Analysis
  34. GRB 201223A: iTelescope optical afterglow observations
  35. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  36. IceCube-201221A: Upper limits from a search for additional neutrino events in IceCube
  37. IceCube-201222A: No significant detection in HAWC
  38. IceCube-201221A: No significant detection in HAWC
  39. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  40. Fermi-LAT Gamma-ray Observations of IceCube-201222A
  41. Fermi-LAT Gamma-ray Observations of IceCube-201221A
  42. Konus-Wind detection of GRB 201221D (short)
  43. IceCube-201222A: IceCube observation of a high-energy neutrino candidate event
  44. GRB 201221A: Swift-XRT refined Analysis
  45. IceCube-201221A: IceCube observation of a high-energy neutrino candidate event
  46. GRB 201221A: FRAM-Auger optical limit
  47. Swift GRB 201221A: Global MASTER-Net observations report
  48. GRB 201221A: Swift detection of a burst
  49. Konus-Wind observation of GRB 201218A
  50. GRB 201214A: Swift-XRT afterglow detection
  51. Fermi GRB 201218A: Global MASTER-Net observations report
  52. Konus-Wind detection of GRB 201216C
  53. IceCube-201209A : MAXI/GSC upper limit
  54. GRB 201216C: Swift-BAT refined analysis
  55. GRB 201216C: Fermi-LAT upper limit
  56. GRB 201216C: AstroSat CZTI detection
  57. GRB 201216C: Swift-XRT observations
  58. GRB 201216C: Swift detection of a burst
  59. Fermi GRB 201216A: Global MASTER-Net observations report
  60. GRB 201216B: AGILE detection of a burst
  61. Chandra observations of GW170817 at ~3.3 years since merger (Full report)
  62. IceCube-201209: No significant detection in HAWC
  63. Potential X-ray KN afterglow from Chandra observations of GW170817 ~3.3 years since merger (3 Epochs of 4)
  64. GRB 201214A: Mates' birthday GRB optical limit from FRAM-ORM
  65. GRB 201214A: A long GRB detected by INTEGRAL
  66. Integral GRB201214.26: Global MASTER-Net observations report
  67. GRB 201015A: optical observations and supernova identification
  68. GRB 201203A: Zeiss-1000 (Koshka observatory) optical upper limit
  69. Fermi-LAT Gamma-ray Observations of IceCube-201209A
  70. GRB 201209A: Swift-BAT refined analysis
  71. Chandra observations of GW170817 at ~3.3 years since merger (Observation 1 of 4)
  72. GRB 201209A: Swift-XRT refined Analysis
  73. IceCube-201209A: IceCube observation of a high-energy neutrino candidate event
  74. GRB 201209A: AstroSat CZTI detection
  75. GRB 201207A: AGILE detection
  76. GRB 201209A: KAIT Optical Upper Limit
  77. GRB 201209A: FRAM-Auger optical limit
  78. GRB 201209A: Swift detection of a burst
  79. GRB 201208A: Fermi-LAT detection
  80. GRB 201208A: AstroSat CZTI detection
  81. GRB 201203A: Swift-BAT refined analysis
  82. Swift follow-up observations of the flat spectrum radio quasar PMN J0206-1150 in the error region of IceCube-201130A
  83. GRB 201203A: Swift-XRT afterglow detection
  84. GRB 201203A: KAIT Optical Upper Limit
  85. GRB 201203A: FRAM-Auger optical limit
  86. GRB 201203A: Swift detection of a burst
  87. IceCube-201130A: No significant detection in HAWC
  88. IceCube-201130A: Upper limits from a search for additional neutrino events in IceCube
  89. IceCube-201130A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  90. Swift observations of the Fermi-LAT source 4FGL J0206.4-1151 in the error region of IceCube-201130A
  91. Fermi-LAT Gamma-ray Observations of IceCube-201130A
  92. Fermi GRB 201201A: Global MASTER-Net observations report
  93. Swift-XRT observations of IceCube 201130A
  94. IceCube-201130A: IceCube observation of a high-energy neutrino candidate event
  95. IceCube Alert 201130.85: Global MASTER-Net observations report
  96. GRB 201128A: Swift-XRT refined Analysis
  97. Fermi trigger No 628278856: Global MASTER-Net observations report
  98. GRB 201128A: Swift detection of a burst
  99. IceCube-201114A: Updated photometry for three DECam candidate optical counterparts
  100. IceCube-201120A in the Cygnus region: No enhanced TeV gamma-ray flux detected by HAWC

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