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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').

577 results found.

  1. Swift Detection of probable new Swift SGR J1555.2-5402
  2. Fermi GBM observation of a bright burst from magneta
  3. Fermi/GBM observation of a burst from SGR 1830-0645
  4. Swift Trigger 1033144: Detection of SGR 1830-0645
  5. Swift Trigger 1032350: Detection of SGR 1830-0645
  6. SGR 1935+2154: MAXI/GSC detection
  7. Fermi GBM Observations of a bright burst from SGR J1935+2154
  8. Recent activity of SGR 1935+2154 as observed by CGBM
  9. INTEGRAL detection of a short burst from SGR 1935+2154
  10. GECAM observations of SGR 1935+2154
  11. Fermi GBM Observations of SGR J1935+2154
  12. Konus-Wind detection of two bright bursts from SGR 1935+2154
  13. IPN triangulation of a bright burst from SGR 1935+2154
  14. GECAM detection of a short burst probably from SGR 1935+2154
  15. IPN triangulation of GRB 210124B (short)
  16. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  17. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  18. GRB 210119A: Fermi GBM observation
  19. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  20. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  21. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  22. Swift Trigger 1005428: Detection of SGR 1830-0645
  23. Swift Trigger 1004219: Detection of SGR 1830-0645
  24. SGR 1830-0645: Swift/UVOT Upper Limits
  25. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  26. Fermi trigger No 624139481: AGILE detection
  27. SGR 1830-0645: pre-discovery detection in Swift/BAT
  28. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  29. SGR 1830-0645: Swift-BAT refined analysis
  30. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  31. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  32. AX J1846.4-0258: Swift-BAT refined analysis
  33. Swift Detection of an SGR-like flare from AX J1846.4-0258
  34. Fermi GBM trigger 616776657/200718619 is not a GRB
  35. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  36. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  37. 1RXS J1708−4009: Swift-BAT refined analysis
  38. Swift detection of an SGR-like burst from 1RXS J1708−4009
  39. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  40. Swift Detection of a burst from SGR Swift J1818.0-1607
  41. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  42. SGR 1935+2154: AstroSat CZTI detection
  43. Insight-HXMT's continued observation plan for SGR J1935+2154
  44. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  45. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  46. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  47. Swift Detection of a burst from SGR Swift J1818.0-1607
  48. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  49. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  50. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  51. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  52. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  53. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  54. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  55. Trigger 968731: Swift detection of SGR1806-20
  56. Fermi GBM trigger 200429866/609886052 is not a GRB
  57. SGR 1935+2154: MASTER optical observations
  58. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  59. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  60. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  61. A Forest of Bursts from SGR 1935+2154
  62. SGR 1935+2154: AstroSat CZTI detections
  63. high bursting activity of SGR 1935+2154: CGBM observations
  64. SGR 1935+2154 the Insight-HXMT observation plan
  65. SGR 1935+2154: MAXI/GSC detection
  66. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  67. Swift detection of multiple bursts from SGR 1935+2154
  68. Konus-Wind observation of a bright burst from SGR 1935+2154
  69. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  70. IPN Triangulation of a bright burst from SGR 1935+2154
  71. bright SGR burst detected by CALET Gamma-Ray Burst Monitor
  72. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  73. Konus-Wind observation of a bright burst from SGR 1935+2154
  74. SGR 1935+2154: Fermi GBM observation
  75. IPN Triangulation of a bright burst from SGR 1935+2154
  76. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  77. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  78. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  79. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  80. Konus-Wind observation of the recent SGR 1935+2154 activity
  81. Swift trigger 933276 MASTER observation
  82. Trigger 933285: Swift detection of the brightest burst so far from SGR 1935+2154
  83. Trigger 933276: Swift detection of further activity from SGR 1935+2154
  84. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  85. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  86. SGR 1935+2154: Swift-BAT refined analysis
  87. GRB 191104B/GRB 191104C are SGR 1935+2154
  88. Trigger 933083: Swift detection of SGR 1935+2154
  89. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  90. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  91. GRB 190326A: Swift XRT and UVOT follow-up observations
  92. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  93. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  94. Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
  95. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  96. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  97. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  98. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  99. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  100. GRB 170524A: Swift detection of a burst (or possible new SGR)

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