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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

603 results found.

  1. GRB 250815A: Fermi GBM Final Localization
  2. The EP-WXT trigger 01709198251 is likely a flaring star
  3. Swift detection of the Soft Gamma Repeater PSR J1647-4552
  4. Fermi Gamma-ray Burst Monitor trigger 772838080/250628885 is not a GRB
  5. GRB 250621B: SVOM/GRM detection of a possible magnetar X-ray burst
  6. GECAM-A detection of a bright burst from SGR 1E1841-045
  7. Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
  8. IPN triangulation of a bright burst from SGR 1E1841-045
  9. GRB 250116A: GECAM-B detection of a long burst
  10. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  11. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  12. SVOM/GRM detection of a short burst from SGR 1830
  13. GECAM detection of a short burst from SGR 1830
  14. SVOM/GRM detection of a short burst from SGR 1E1841-045
  15. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  16. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  17. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  18. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  19. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  20. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  21. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  22. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  23. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  24. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  25. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  26. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  27. IPN triangulation of GRB 240112A (long)
  28. GRB 240112A: GECAM detection of a burst
  29. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  30. GECAM-B observation of a short burst from SGR J1555-5402
  31. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  32. SGR 1806-20: Correction to GCN 33494
  33. INTEGRAL detection of a burst from SGR 1806-200
  34. VZLUSAT-2 detection of SGR 1806-20
  35. Trigger 1159327: Swift detection of SGR1806-20
  36. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 December 13
  37. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
  38. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  39. SGR 1935+2154: AstroSat CZTI Detections
  40. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  41. SGR 1935+21542: VZLUSAT-2 and GRBAlpha joint detection
  42. AGILE detection of a burst from SGR J1935+2154 reported by VZLUSAT-2
  43. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  44. AGILE detection of the 2022 October 17 burst from SGR J1935+2154 reported by Konus-Wind
  45. SGR 1935+2154: Detection by GRBAlpha
  46. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 October 17
  47. AGILE detection of short X-ray flaring activity contemporary to SGR J1935+2154 reported bursts
  48. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  49. Konus-Wind observation of the recent SGR 1935+2154 activity
  50. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  51. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  52. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  53. INTEGRAL shows increasing activity in SGR J1935+2154
  54. INTEGRAL detection of a burst from SGR J1935+2154
  55. INTEGRAL detection of a burst from SGR J1935+2154
  56. Fermi GBM trigger 686350260/221001869 is not a GRB
  57. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on June 16
  58. Trigger 1108538: Swift detection of a burst from SGR J1935+2154
  59. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 May 25
  60. GRB 220211A: redshift lower limit estimating
  61. Fermi GBM trigger 666393834/220212892 is not a GRB
  62. GECAM observations of a series of bursts from SGR J1935+2154
  63. AGILE observations of a bright burst from SGR 1935+2154
  64. Konus-Wind detection of an intermediate flare from SGR 1935+2154 on January 20
  65. IPN triangulation of a bright burst from SGR 1935+2154
  66. Konus-Wind observation of the recent SGR 1935+2154 activity
  67. GECAM observations of a series of bursts from SGR J1935+2154
  68. GECAM observations of a series of bursts from SGR J1935+2154
  69. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  70. AGILE observations of a burst from SGR 1935+2154
  71. GECAM observations of a series of bursts from SGR J1935+2154
  72. Fermi Gamma-ray Burst Monitor trigger 220111325/663580106 is not a GRB
  73. GECAM observations of a series of bursts from SGR J1935+2154
  74. GECAM observation of a burst from SGR J1555.2-5402
  75. GECAM detection of a short burst from SGR 1935+2154
  76. GECAM observations of a series of bursts from SGR J1935+2154
  77. GRB 211229A: GECAM detection
  78. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  79. AGILE observations of a bright burst from SGR 1935+2154
  80. GECAM detection of a short burst probably from SGR J1555.2-5402
  81. Fermi Gamma-ray Burst Monitor trigger 211008665/655401471 is not a GRB
  82. GECAM observation of a burst from SGR J1555.2-5402
  83. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  84. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  85. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  86. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  87. Konus-Wind observation of the recent SGR 1935+2154 activity
  88. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  89. AGILE observations of two bright bursts from SGR 1935+2154
  90. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  91. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  92. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  93. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  94. IPN triangulation of a bright burst from SGR 1935+2154
  95. GECAM observations of a series of bursts from SGR J1935+2154
  96. Swift detection of a burst from SGR Swift J1555.2-5402
  97. GECAM observation of a burst from SGR J1935+2154
  98. GECAM observation of a burst from SGR J1935+2154
  99. GECAM observation of a burst from SGR J1555.2-5402
  100. Fermi GBM trigger 652585475 / 210906073 is not a GRB

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