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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"

610 results found.

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

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