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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"

606 results found.

  1. GECAM observation of a burst from SGR J1555.2-5402
  2. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  3. Fermi GBM observation of a burst from SGR J1555.2-5402
  4. POLAR detection of a SGR-like burst
  5. Swift detection of an outburst from SGR Swift J1555.2-5402
  6. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  7. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  8. IPN Triangulation of a bright burst from SGR 1935+2154
  9. GECAM detection of a short burst from SGR J1935+2154
  10. Recent activity of SGR 1935+2154 as observed by CGBM
  11. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  12. GECAM detection of a short burst from SGR J1935+2154
  13. GECAM detection of a short burst from SGR J1935+2154
  14. GECAM detection of a short burst from SGR 1935+2154
  15. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  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 6
  18. Fermi GBM Observations of SGR J1935+2154
  19. Swift-BAT detection of a burst from SGR 1935+2154
  20. GECAM detection of a bright short burst from SGR 1935+2154
  21. INTEGRAL detection of a burst from SGR 1935+2154
  22. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  23. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  24. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  25. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  26. SGR J1555.2-5402: Swift-BAT refined analysis
  27. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  28. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  29. Swift Detection of probable new Swift SGR J1555.2-5402
  30. Fermi GBM observation of a bright burst from magneta
  31. Fermi/GBM observation of a burst from SGR 1830-0645
  32. Swift Trigger 1033144: Detection of SGR 1830-0645
  33. Swift Trigger 1032350: Detection of SGR 1830-0645
  34. SGR 1935+2154: MAXI/GSC detection
  35. Fermi GBM Observations of a bright burst from SGR J1935+2154
  36. Recent activity of SGR 1935+2154 as observed by CGBM
  37. INTEGRAL detection of a short burst from SGR 1935+2154
  38. GECAM observations of SGR 1935+2154
  39. Fermi GBM Observations of SGR J1935+2154
  40. Konus-Wind detection of two bright bursts from SGR 1935+2154
  41. IPN triangulation of a bright burst from SGR 1935+2154
  42. GECAM detection of a short burst probably from SGR 1935+2154
  43. IPN triangulation of GRB 210124B (short)
  44. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  45. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  46. GRB 210119A: Fermi GBM observation
  47. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  48. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  49. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  50. Swift Trigger 1005428: Detection of SGR 1830-0645
  51. Swift Trigger 1004219: Detection of SGR 1830-0645
  52. Alert from the HAWC Burst Monitor HAWC-201019A
  53. SGR 1830-0645: Swift/UVOT Upper Limits
  54. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  55. Fermi trigger No 624139481: AGILE detection
  56. SGR 1830-0645: pre-discovery detection in Swift/BAT
  57. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  58. SGR 1830-0645: Swift-BAT refined analysis
  59. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  60. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  61. AX J1846.4-0258: Swift-BAT refined analysis
  62. Swift Detection of an SGR-like flare from AX J1846.4-0258
  63. Fermi GBM trigger 616776657/200718619 is not a GRB
  64. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  65. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  66. 1RXS J1708−4009: Swift-BAT refined analysis
  67. Swift detection of an SGR-like burst from 1RXS J1708−4009
  68. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  69. Swift Detection of a burst from SGR Swift J1818.0-1607
  70. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  71. SGR 1935+2154: AstroSat CZTI detection
  72. Insight-HXMT's continued observation plan for SGR J1935+2154
  73. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  74. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  75. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  76. Swift Detection of a burst from SGR Swift J1818.0-1607
  77. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  78. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  79. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  80. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  81. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  82. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  83. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  84. Trigger 968731: Swift detection of SGR1806-20
  85. Fermi GBM trigger 200429866/609886052 is not a GRB
  86. SGR 1935+2154: MASTER optical observations
  87. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  88. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  89. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  90. A Forest of Bursts from SGR 1935+2154
  91. SGR 1935+2154: AstroSat CZTI detections
  92. high bursting activity of SGR 1935+2154: CGBM observations
  93. SGR 1935+2154 the Insight-HXMT observation plan
  94. SGR 1935+2154: MAXI/GSC detection
  95. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  96. Swift detection of multiple bursts from SGR 1935+2154
  97. Konus-Wind observation of a bright burst from SGR 1935+2154
  98. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  99. IPN Triangulation of a bright burst from SGR 1935+2154
  100. bright SGR burst detected by CALET Gamma-Ray Burst Monitor

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