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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

900 results found.

  1. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  2. AGILE observations of two bright bursts from SGR 1935+2154
  3. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  4. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  5. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  6. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  7. IPN triangulation of a bright burst from SGR 1935+2154
  8. GECAM observations of a series of bursts from SGR J1935+2154
  9. Swift detection of a burst from SGR Swift J1555.2-5402
  10. GECAM observation of a burst from SGR J1935+2154
  11. GECAM observation of a burst from SGR J1935+2154
  12. GECAM observation of a burst from SGR J1555.2-5402
  13. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  14. Fermi GBM observation of a burst from SGR J1555.2-5402
  15. POLAR detection of a SGR-like burst
  16. Swift detection of an outburst from SGR Swift J1555.2-5402
  17. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  18. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  19. IPN Triangulation of a bright burst from SGR 1935+2154
  20. IceCube-210730A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  21. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  22. GECAM detection of a short burst from SGR J1935+2154
  23. Recent activity of SGR 1935+2154 as observed by CGBM
  24. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  25. GECAM detection of a short burst from SGR J1935+2154
  26. GECAM detection of a short burst from SGR J1935+2154
  27. GECAM detection of a short burst from SGR 1935+2154
  28. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  29. GECAM detection of a short burst from SGR 1935+2154
  30. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  31. Fermi GBM Observations of SGR J1935+2154
  32. Swift-BAT detection of a burst from SGR 1935+2154
  33. GECAM detection of a bright short burst from SGR 1935+2154
  34. INTEGRAL detection of a burst from SGR 1935+2154
  35. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  36. IceCube-210510A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  37. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  38. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  39. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  40. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  41. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  42. SGR J1555.2-5402: Swift-BAT refined analysis
  43. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  44. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  45. Swift Detection of probable new Swift SGR J1555.2-5402
  46. Fermi GBM observation of a bright burst from magneta
  47. Fermi GRB 210510A: Global MASTER-Net observations report
  48. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  49. GRB 210402A: MASTER prompt and follow up optical observation
  50. Fermi/GBM observation of a burst from SGR 1830-0645
  51. Swift Trigger 1033144: Detection of SGR 1830-0645
  52. Swift Trigger 1032350: Detection of SGR 1830-0645
  53. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  54. IceCube-210210A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  55. SGR 1935+2154: MAXI/GSC detection
  56. Fermi GBM Observations of a bright burst from SGR J1935+2154
  57. Recent activity of SGR 1935+2154 as observed by CGBM
  58. INTEGRAL detection of a short burst from SGR 1935+2154
  59. GECAM observations of SGR 1935+2154
  60. Fermi GBM Observations of SGR J1935+2154
  61. Konus-Wind detection of two bright bursts from SGR 1935+2154
  62. IPN triangulation of a bright burst from SGR 1935+2154
  63. GECAM detection of a short burst probably from SGR 1935+2154
  64. IPN triangulation of GRB 210124B (short)
  65. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  66. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  67. GRB 210119A: Fermi GBM observation
  68. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  69. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  70. NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  71. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  72. IceCube-201222A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  73. IceCube-201221A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  74. IceCube-201209A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  75. IceCube-201130A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  76. IceCube-201120A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  77. IceCube-201115A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  78. IceCube-201114A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  79. VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
  80. Swift Trigger 1005428: Detection of SGR 1830-0645
  81. Swift Trigger 1004219: Detection of SGR 1830-0645
  82. IceCube-201021A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  83. IceCube-201014A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  84. SGR 1830-0645: Swift/UVOT Upper Limits
  85. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  86. Fermi trigger No 624139481: AGILE detection
  87. SGR 1830-0645: pre-discovery detection in Swift/BAT
  88. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  89. SGR 1830-0645: Swift-BAT refined analysis
  90. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  91. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  92. IceCube-201007A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  93. IceCube-200926B: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  94. IceCube-200929A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  95. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  96. IceCube-200921A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  97. IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  98. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  99. IceCube-200911A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  100. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation

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