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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 GRB 250312B: Global MASTER-Net observations report
  2. GECAM-A detection of a bright burst from SGR 1E1841-045
  3. Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
  4. IPN triangulation of a bright burst from SGR 1E1841-045
  5. GRB 250116A: GECAM-B detection of a long burst
  6. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  7. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  8. SVOM/GRM detection of a short burst from SGR 1830
  9. GECAM detection of a short burst from SGR 1830
  10. SVOM/GRM detection of a short burst from SGR 1E1841-045
  11. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  12. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  13. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  14. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  15. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  16. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  17. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  18. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  19. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  20. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  21. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  22. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  23. GRB 240529A: Swift/UVOT Detection
  24. GRB 240225B: AstroSat CZTI detection
  25. IPN triangulation of GRB 240112A (long)
  26. GRB 240112A: GECAM detection of a burst
  27. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  28. GECAM-B observation of a short burst from SGR J1555-5402
  29. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  30. GRB 230919A: Fermi GBM Observation
  31. SGR 1806-20: Correction to GCN 33494
  32. INTEGRAL detection of a burst from SGR 1806-200
  33. VZLUSAT-2 detection of SGR 1806-20
  34. Trigger 1159327: Swift detection of SGR1806-20
  35. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 December 13
  36. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
  37. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  38. SGR 1935+2154: AstroSat CZTI Detections
  39. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  40. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  41. AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
  42. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  43. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  44. SGR 1935+2154: Detection by GRBAlpha
  45. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 October 17
  46. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  47. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  48. Konus-Wind observation of the recent SGR 1935+2154 activity
  49. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  50. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  51. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  52. INTEGRAL shows increasing activity in SGR J1935+2154
  53. INTEGRAL detection of a burst from SGR J1935+2154
  54. INTEGRAL detection of a burst from SGR J1935+2154
  55. Fermi GBM trigger 686350260/221001869 is not a GRB
  56. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on June 16
  57. Trigger 1108538: Swift detection of a burst from SGR J1935+2154
  58. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 May 25
  59. GRB 220211A: redshift lower limit estimating
  60. Fermi GBM trigger 666393834/220212892 is not a GRB
  61. GECAM observations of a series of bursts from SGR J1935+2154
  62. AGILE observations of a bright burst from SGR 1935+2154
  63. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on January 20
  64. IPN triangulation of a bright burst from SGR 1935+2154
  65. Konus-Wind observation of the recent SGR 1935+2154 activity
  66. GECAM observations of a series of bursts from SGR J1935+2154
  67. GECAM observations of a series of bursts from SGR J1935+2154
  68. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  69. AGILE observations of a burst from SGR 1935+2154
  70. GECAM observations of a series of bursts from SGR J1935+2154
  71. Fermi Gamma-ray Burst Monitor trigger 220111325/663580106 is not a GRB
  72. GECAM observations of a series of bursts from SGR J1935+2154
  73. GECAM observation of a burst from SGR J1555.2-5402
  74. GECAM detection of a short burst from SGR 1935+2154
  75. GECAM observations of a series of bursts from SGR J1935+2154
  76. GRB 211229A: GECAM detection
  77. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  78. AGILE observations of a bright burst from SGR 1935+2154
  79. GECAM detection of a short burst probably from SGR J1555.2-5402
  80. Fermi Gamma-ray Burst Monitor trigger 211008665/655401471 is not a GRB
  81. GECAM observation of a burst from SGR J1555.2-5402
  82. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  83. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  84. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  85. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  86. Konus-Wind observation of the recent SGR 1935+2154 activity
  87. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  88. AGILE observations of two bright bursts from SGR 1935+2154
  89. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  90. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  91. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  92. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  93. IPN triangulation of a bright burst from SGR 1935+2154
  94. GECAM observations of a series of bursts from SGR J1935+2154
  95. Swift detection of a burst from SGR Swift J1555.2-5402
  96. GECAM observation of a burst from SGR J1935+2154
  97. GECAM observation of a burst from SGR J1935+2154
  98. GECAM observation of a burst from SGR J1555.2-5402
  99. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  100. Fermi GBM observation of a burst from SGR J1555.2-5402

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