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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"

12190 results found.

  1. Fermi-LAT Gamma-ray Observations of IceCube-201014A
  2. GRB 201013A: FRAM-ORM possible afterglow candidate
  3. GRB 201013A: Swift-XRT refined Analysis
  4. SGR 1830-0645: Swift/UVOT Upper Limits
  5. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  6. Fermi trigger No 624139481: AGILE detection
  7. SGR 1830-0645: pre-discovery detection in Swift/BAT
  8. Fermi trigger No 624139481: Global MASTER-Net observations report
  9. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  10. Fermi trigger No 624121589: Global MASTER-Net observations report
  11. SGR 1830-0645: Swift-BAT refined analysis
  12. GRB 201006A: Chandra upper limit on the X-ray afterglow
  13. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  14. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  15. IceCube-201007A: No significant detection in HAWC
  16. IceCube-200926A: Upper limits from Insight-HXMT Observations
  17. Fermi-LAT Gamma-ray Observations of IceCube-201007A
  18. IceCube-201007A - IceCube observation of a high-energy neutrino candidate track-like event
  19. GRB 201006A: GROWTH-India Telescope optical upper limit
  20. Fermi GRB 201007A: Global MASTER-Net observations report
  21. Swift GRB201006.05: Global MASTER-Net observations report
  22. Fermi trigger No 623470566: Global MASTER-Net observations report
  23. Fermi trigger No 623493962: Global MASTER-Net observations report
  24. GRB 201001A: Swift-BAT refined analysis
  25. Fermi-LAT Gamma-ray Observations of IceCube-200929A
  26. IceCube-200929A: IceCube observation of a high-energy neutrino candidate event
  27. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  28. Konus-Wind detection of GRB 200920B
  29. Fermi-LAT Gamma-ray Observations of IceCube-200926A
  30. IceCube-200926B: IceCube observation of a high-energy neutrino candidate event
  31. GRB 200925B: Swift-XRT refined Analysis
  32. IceCube-200926A: IceCube observation of a high-energy neutrino candidate event
  33. GRB 200925B: Swift detection of a burst
  34. Swift GRB200925.91: Global MASTER-Net observations report
  35. Fermi GRB 200925A: Global MASTER-Net observations report
  36. Konus-Wind observation of GRB 200914A
  37. GRB 200924A: Fermi GBM Final Real-time Localization
  38. Fermi GRB 200923A: Global MASTER-Net observations report
  39. IceCube Alert 200921.80: Global MASTER-Net observations report
  40. IceCube-200921A: Upper limits from a search for additional neutrino events in IceCube
  41. Fermi-LAT Gamma-ray Observations of IceCube-200921A and detection of a new gamma-ray source, Fermi J1256.9+2630
  42. Fermi GRB 200922B: Global MASTER-Net observations report
  43. GRB 200922A: Swift-XRT refined Analysis
  44. GRB 200922A: Swift detection of a burst with possible optical counterpart
  45. IceCube-200921A: IceCube observation of a high-energy neutrino candidate event
  46. GRB 200920B: AGILE/MCAL detection of a burst
  47. GRB 200920A: Fermi GBM Final Real-time Localization
  48. Fermi GRB 200919C: Global MASTER-Net observations report
  49. Swift GRB200919.08: Global MASTER-Net observations report
  50. GRB 200919A: Swift detection of a burst
  51. IceCube-200916A: AbAO observations of optical candidates ZTF20acaapwk/AT2020tno, ZTF20acaapwo/AT2020tnp
  52. IceCube-200916A: Upper limits from a search for additional neutrino events in IceCube
  53. Swift-XRT observations of IceCube 200916A
  54. IceCube-200916A: No significant detection in HAWC
  55. IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  56. IceCube-200916A: Two Candidate Counterparts from the Zwicky Transient Facility
  57. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  58. IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
  59. Fermi GRB 200916A: Global MASTER-Net observations report
  60. Integral GRB200914.53: Global MASTER-Net observations report
  61. Fermi GRB 200914A: Global MASTER-Net observations report
  62. IceCube Alert 200914.00: Global MASTER-Net observations report
  63. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  64. GRB 200914A : A long GRB detected by INTEGRAL
  65. IceCube-200911A: IceCube observation of a high-energy neutrino candidate event
  66. IPN triangulation of GRB 200907A (short)
  67. GRB 200909B: Swift-BAT refined analysis
  68. Swift GRB200909.97: Global MASTER-Net observations report
  69. GRB 200909A: AstroSat CZTI detection
  70. GRB 200829A: T100 observations
  71. Fermi GRB 200909A: Global MASTER-Net observations report
  72. Fermi GRB 200908A: Global MASTER-Net observations report
  73. Konus-Wind detection of GRB 200903E
  74. Fermi GRB 200907C: Global MASTER-Net observations report
  75. Fermi GRB 200906A: Global MASTER-Net observations report
  76. GRB 200906A: Swift-XRT refined Analysis
  77. GRB 200906A: Swift detection of a burst
  78. GRB 200903D: MAXI/GSC detection
  79. GRB 200903A: Swift-BAT refined analysis
  80. GRB200817B: AstroSat CZTI detection
  81. Fermi GRB 200903B: Global MASTER-Net observations report
  82. GRB 200901A: MASTER OT early detection
  83. GRB 200901A: Swift-XRT refined Analysis
  84. Swift GRB200901.16: Global MASTER-Net observations report
  85. GRB 200829A: Koshka Zeiss-1000 optical observations
  86. GRB 200829A: Liverpool Telescope observations
  87. GRB 200829A: Fermi GBM detection
  88. Konus-Wind detection of GRB 200829A (a clone of GRB 200826B?)
  89. GRB 200829A: Swift-XRT refined Analysis
  90. GRB 200829A: AGILE/MCAL detection
  91. GRB 200829A: Swift detection of a burst with an optical afterglow
  92. Zwicky Transient Facility discovery of ZTF20abtxwfx/AT2020sev, a fast optical transient and candidate afterglow
  93. Konus-Wind detection of GRB 200826B
  94. GRB 200826A: Swift-XRT afterglow detection
  95. Fermi GRB 200826B: Global MASTER-Net observations report
  96. Fermi GRB 200824A: Global MASTER-Net observations report
  97. Konus-Wind detection of GRB 200826A
  98. Fermi GRB 200826A: Global MASTER-Net observations report
  99. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  100. Swift Trigger 992444: a possible GRB 200821A

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