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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"

602 results found.

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

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