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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').
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"

613 results found.

  1. GECAM observation of a burst from SGR J1935+2154
  2. GECAM observation of a burst from SGR J1555.2-5402
  3. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  4. Fermi GBM observation of a burst from SGR J1555.2-5402
  5. POLAR detection of a SGR-like burst
  6. Swift detection of an outburst from SGR Swift J1555.2-5402
  7. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  8. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  9. IPN Triangulation of a bright burst from SGR 1935+2154
  10. Fermi trigger No 649814537: Global MASTER-Net observations report
  11. GECAM detection of a short burst from SGR J1935+2154
  12. Recent activity of SGR 1935+2154 as observed by CGBM
  13. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  14. GECAM detection of a short burst from SGR J1935+2154
  15. GECAM detection of a short burst from SGR J1935+2154
  16. GECAM detection of a short burst from SGR 1935+2154
  17. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  18. GECAM detection of a short burst from SGR 1935+2154
  19. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  20. Fermi GBM Observations of SGR J1935+2154
  21. Swift-BAT detection of a burst from SGR 1935+2154
  22. GECAM detection of a bright short burst from SGR 1935+2154
  23. INTEGRAL detection of a burst from SGR 1935+2154
  24. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  25. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  26. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  27. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  28. SGR J1555.2-5402: Swift-BAT refined analysis
  29. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  30. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  31. Swift Detection of probable new Swift SGR J1555.2-5402
  32. Fermi GBM observation of a bright burst from magneta
  33. Fermi/GBM observation of a burst from SGR 1830-0645
  34. Swift Trigger 1033144: Detection of SGR 1830-0645
  35. Swift Trigger 1032350: Detection of SGR 1830-0645
  36. SGR 1935+2154: MAXI/GSC detection
  37. Fermi GBM Observations of a bright burst from SGR J1935+2154
  38. Recent activity of SGR 1935+2154 as observed by CGBM
  39. INTEGRAL detection of a short burst from SGR 1935+2154
  40. GECAM observations of SGR 1935+2154
  41. Fermi GBM Observations of SGR J1935+2154
  42. Konus-Wind detection of two bright bursts from SGR 1935+2154
  43. IPN triangulation of a bright burst from SGR 1935+2154
  44. GECAM detection of a short burst probably from SGR 1935+2154
  45. IPN triangulation of GRB 210124B (short)
  46. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  47. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  48. GRB 210119A: Fermi GBM observation
  49. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  50. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  51. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  52. Swift Trigger 1005428: Detection of SGR 1830-0645
  53. Swift Trigger 1004219: Detection of SGR 1830-0645
  54. GRB 201029A: Swift/UVOT Upper Limits
  55. SGR 1830-0645: Swift/UVOT Upper Limits
  56. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  57. Fermi trigger No 624139481: AGILE detection
  58. SGR 1830-0645: pre-discovery detection in Swift/BAT
  59. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  60. SGR 1830-0645: Swift-BAT refined analysis
  61. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  62. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  63. AX J1846.4-0258: Swift-BAT refined analysis
  64. Swift Detection of an SGR-like flare from AX J1846.4-0258
  65. Fermi GBM trigger 616776657/200718619 is not a GRB
  66. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  67. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  68. 1RXS J1708−4009: Swift-BAT refined analysis
  69. Swift detection of an SGR-like burst from 1RXS J1708−4009
  70. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  71. Swift Detection of a burst from SGR Swift J1818.0-1607
  72. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  73. SGR 1935+2154: AstroSat CZTI detection
  74. Insight-HXMT's continued observation plan for SGR J1935+2154
  75. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  76. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  77. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  78. Swift Detection of a burst from SGR Swift J1818.0-1607
  79. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  80. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  81. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  82. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  83. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  84. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  85. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  86. Trigger 968731: Swift detection of SGR1806-20
  87. Fermi GBM trigger 200429866/609886052 is not a GRB
  88. SGR 1935+2154: MASTER optical observations
  89. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  90. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  91. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  92. A Forest of Bursts from SGR 1935+2154
  93. SGR 1935+2154: AstroSat CZTI detections
  94. high bursting activity of SGR 1935+2154: CGBM observations
  95. SGR 1935+2154 the Insight-HXMT observation plan
  96. SGR 1935+2154: MAXI/GSC detection
  97. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  98. Swift detection of multiple bursts from SGR 1935+2154
  99. Konus-Wind observation of a bright burst from SGR 1935+2154
  100. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations

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