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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').

581 results found.

  1. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  2. SGR J1555.2-5402: Swift-BAT refined analysis
  3. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  4. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  5. Swift Detection of probable new Swift SGR J1555.2-5402
  6. Fermi GBM observation of a bright burst from magneta
  7. Fermi/GBM observation of a burst from SGR 1830-0645
  8. Swift Trigger 1033144: Detection of SGR 1830-0645
  9. Swift Trigger 1032350: Detection of SGR 1830-0645
  10. SGR 1935+2154: MAXI/GSC detection
  11. Fermi GBM Observations of a bright burst from SGR J1935+2154
  12. Recent activity of SGR 1935+2154 as observed by CGBM
  13. INTEGRAL detection of a short burst from SGR 1935+2154
  14. GECAM observations of SGR 1935+2154
  15. Fermi GBM Observations of SGR J1935+2154
  16. Konus-Wind detection of two bright bursts from SGR 1935+2154
  17. IPN triangulation of a bright burst from SGR 1935+2154
  18. GECAM detection of a short burst probably from SGR 1935+2154
  19. IPN triangulation of GRB 210124B (short)
  20. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  21. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  22. GRB 210119A: Fermi GBM observation
  23. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  24. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  25. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  26. Swift Trigger 1005428: Detection of SGR 1830-0645
  27. Swift Trigger 1004219: Detection of SGR 1830-0645
  28. SGR 1830-0645: Swift/UVOT Upper Limits
  29. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  30. Fermi trigger No 624139481: AGILE detection
  31. SGR 1830-0645: pre-discovery detection in Swift/BAT
  32. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  33. SGR 1830-0645: Swift-BAT refined analysis
  34. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  35. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  36. AX J1846.4-0258: Swift-BAT refined analysis
  37. Swift Detection of an SGR-like flare from AX J1846.4-0258
  38. Fermi GBM trigger 616776657/200718619 is not a GRB
  39. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  40. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  41. 1RXS J1708−4009: Swift-BAT refined analysis
  42. Swift detection of an SGR-like burst from 1RXS J1708−4009
  43. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  44. Swift Detection of a burst from SGR Swift J1818.0-1607
  45. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  46. SGR 1935+2154: AstroSat CZTI detection
  47. Insight-HXMT's continued observation plan for SGR J1935+2154
  48. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  49. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  50. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  51. Swift Detection of a burst from SGR Swift J1818.0-1607
  52. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  53. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  54. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  55. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  56. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  57. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  58. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  59. Trigger 968731: Swift detection of SGR1806-20
  60. Fermi GBM trigger 200429866/609886052 is not a GRB
  61. SGR 1935+2154: MASTER optical observations
  62. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  63. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  64. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  65. A Forest of Bursts from SGR 1935+2154
  66. SGR 1935+2154: AstroSat CZTI detections
  67. high bursting activity of SGR 1935+2154: CGBM observations
  68. SGR 1935+2154 the Insight-HXMT observation plan
  69. SGR 1935+2154: MAXI/GSC detection
  70. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  71. Swift detection of multiple bursts from SGR 1935+2154
  72. Konus-Wind observation of a bright burst from SGR 1935+2154
  73. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  74. IPN Triangulation of a bright burst from SGR 1935+2154
  75. bright SGR burst detected by CALET Gamma-Ray Burst Monitor
  76. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  77. Konus-Wind observation of a bright burst from SGR 1935+2154
  78. SGR 1935+2154: Fermi GBM observation
  79. IPN Triangulation of a bright burst from SGR 1935+2154
  80. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  81. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  82. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  83. GRB 200306C: Enhanced Swift-XRT position
  84. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  85. Konus-Wind observation of the recent SGR 1935+2154 activity
  86. Swift trigger 933276 MASTER observation
  87. Trigger 933285: Swift detection of the brightest burst so far from SGR 1935+2154
  88. Trigger 933276: Swift detection of further activity from SGR 1935+2154
  89. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  90. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  91. SGR 1935+2154: Swift-BAT refined analysis
  92. GRB 191104B/GRB 191104C are SGR 1935+2154
  93. Trigger 933083: Swift detection of SGR 1935+2154
  94. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  95. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  96. GRB 190326A: Swift XRT and UVOT follow-up observations
  97. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  98. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  99. Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
  100. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552

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