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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').
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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"

11857 results found.

  1. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  2. GRB 201015A: Assy and Mondy optical observations
  3. GRB 201015A: FRAM-ORM afterglow detection
  4. Konus-Wind observation of GRB 201013A
  5. GRB 201014A: Swift-XRT refined Analysis
  6. Swift GRB 201015A: Global MASTER-Net observations report
  7. Fermi-LAT Gamma-ray Observations of IceCube-201014A
  8. GRB 201013A: FRAM-ORM possible afterglow candidate
  9. GRB 201013A: Swift-XRT refined Analysis
  10. Fermi trigger No 624139481: AGILE detection
  11. SGR 1830-0645: pre-discovery detection in Swift/BAT
  12. Fermi trigger No 624139481: Global MASTER-Net observations report
  13. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  14. Fermi trigger No 624121589: Global MASTER-Net observations report
  15. GRB 201006A: Chandra upper limit on the X-ray afterglow
  16. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  17. IceCube-201007A: No significant detection in HAWC
  18. IceCube-200926A: Upper limits from Insight-HXMT Observations
  19. Fermi-LAT Gamma-ray Observations of IceCube-201007A
  20. IceCube-201007A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRB 201006A: GROWTH-India Telescope optical upper limit
  22. Fermi GRB 201007A: Global MASTER-Net observations report
  23. Swift GRB201006.05: Global MASTER-Net observations report
  24. Fermi trigger No 623470566: Global MASTER-Net observations report
  25. Fermi trigger No 623493962: Global MASTER-Net observations report
  26. GRB 201001A: Swift-BAT refined analysis
  27. Fermi-LAT Gamma-ray Observations of IceCube-200929A
  28. IceCube-200929A: IceCube observation of a high-energy neutrino candidate event
  29. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  30. Konus-Wind detection of GRB 200920B
  31. Fermi-LAT Gamma-ray Observations of IceCube-200926A
  32. IceCube-200926B: IceCube observation of a high-energy neutrino candidate event
  33. GRB 200925B: Swift-XRT refined Analysis
  34. IceCube-200926A: IceCube observation of a high-energy neutrino candidate event
  35. GRB 200925B: Swift detection of a burst
  36. Swift GRB200925.91: Global MASTER-Net observations report
  37. Fermi GRB 200925A: Global MASTER-Net observations report
  38. Konus-Wind observation of GRB 200914A
  39. GRB 200924A: Fermi GBM Final Real-time Localization
  40. Fermi GRB 200923A: Global MASTER-Net observations report
  41. IceCube Alert 200921.80: Global MASTER-Net observations report
  42. IceCube-200921A: Upper limits from a search for additional neutrino events in IceCube
  43. Fermi-LAT Gamma-ray Observations of IceCube-200921A and detection of a new gamma-ray source, Fermi J1256.9+2630
  44. Fermi GRB 200922B: Global MASTER-Net observations report
  45. GRB 200922A: Swift-XRT refined Analysis
  46. GRB 200922A: Swift detection of a burst with possible optical counterpart
  47. IceCube-200921A: IceCube observation of a high-energy neutrino candidate event
  48. GRB 200920B: AGILE/MCAL detection of a burst
  49. GRB 200920A: Fermi GBM Final Real-time Localization
  50. Fermi GRB 200919C: Global MASTER-Net observations report
  51. Swift GRB200919.08: Global MASTER-Net observations report
  52. GRB 200919A: Swift detection of a burst
  53. IceCube-200916A: AbAO observations of optical candidates ZTF20acaapwk/AT2020tno, ZTF20acaapwo/AT2020tnp
  54. IceCube-200916A: Upper limits from a search for additional neutrino events in IceCube
  55. Swift-XRT observations of IceCube 200916A
  56. IceCube-200916A: No significant detection in HAWC
  57. IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  58. IceCube-200916A: Two Candidate Counterparts from the Zwicky Transient Facility
  59. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  60. IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
  61. Fermi GRB 200916A: Global MASTER-Net observations report
  62. Integral GRB200914.53: Global MASTER-Net observations report
  63. Fermi GRB 200914A: Global MASTER-Net observations report
  64. IceCube Alert 200914.00: Global MASTER-Net observations report
  65. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  66. GRB 200914A : A long GRB detected by INTEGRAL
  67. IceCube-200911A: IceCube observation of a high-energy neutrino candidate event
  68. IPN triangulation of GRB 200907A (short)
  69. GRB 200909B: Swift-BAT refined analysis
  70. Swift GRB200909.97: Global MASTER-Net observations report
  71. GRB 200909A: AstroSat CZTI detection
  72. GRB 200829A: T100 observations
  73. Fermi GRB 200909A: Global MASTER-Net observations report
  74. Fermi GRB 200908A: Global MASTER-Net observations report
  75. Konus-Wind detection of GRB 200903E
  76. Fermi GRB 200907C: Global MASTER-Net observations report
  77. Fermi GRB 200906A: Global MASTER-Net observations report
  78. GRB 200906A: Swift-XRT refined Analysis
  79. GRB 200906A: Swift detection of a burst
  80. GRB 200903D: MAXI/GSC detection
  81. GRB 200903A: Swift-BAT refined analysis
  82. GRB200817B: AstroSat CZTI detection
  83. Fermi GRB 200903B: Global MASTER-Net observations report
  84. GRB 200901A: MASTER OT early detection
  85. GRB 200901A: Swift-XRT refined Analysis
  86. Swift GRB200901.16: Global MASTER-Net observations report
  87. GRB 200829A: Koshka Zeiss-1000 optical observations
  88. GRB 200829A: Liverpool Telescope observations
  89. GRB 200829A: Fermi GBM detection
  90. Konus-Wind detection of GRB 200829A (a clone of GRB 200826B?)
  91. GRB 200829A: Swift-XRT refined Analysis
  92. GRB 200829A: AGILE/MCAL detection
  93. GRB 200829A: Swift detection of a burst with an optical afterglow
  94. Zwicky Transient Facility discovery of ZTF20abtxwfx/AT2020sev, a fast optical transient and candidate afterglow
  95. Konus-Wind detection of GRB 200826B
  96. GRB 200826A: Swift-XRT afterglow detection
  97. Fermi GRB 200826B: Global MASTER-Net observations report
  98. Fermi GRB 200824A: Global MASTER-Net observations report
  99. Konus-Wind detection of GRB 200826A
  100. Fermi GRB 200826A: Global MASTER-Net observations report

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