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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').

578 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. Alert from the HAWC Burst Monitor HAWC-201019A
  25. SGR 1830-0645: Swift/UVOT Upper Limits
  26. GRB 201011A: Fermi GBM detection of a likely Long GRB in the direction of SGR 1830-0645
  27. Fermi trigger No 624139481: AGILE detection
  28. SGR 1830-0645: pre-discovery detection in Swift/BAT
  29. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  30. SGR 1830-0645: Swift-BAT refined analysis
  31. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  32. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  33. AX J1846.4-0258: Swift-BAT refined analysis
  34. Swift Detection of an SGR-like flare from AX J1846.4-0258
  35. Fermi GBM trigger 616776657/200718619 is not a GRB
  36. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  37. Updated catalog of X-ray bursts of SGR J1935+2154 from Insight-HXMT observations
  38. 1RXS J1708−4009: Swift-BAT refined analysis
  39. Swift detection of an SGR-like burst from 1RXS J1708−4009
  40. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  41. Swift Detection of a burst from SGR Swift J1818.0-1607
  42. AGILE detection of a burst from SGR 1935+2154 on May 10, 2020
  43. SGR 1935+2154: AstroSat CZTI detection
  44. Insight-HXMT's continued observation plan for SGR J1935+2154
  45. Konus-Wind observation of SGR 1935+2154 activity on 2020 May 10
  46. IPN triangulation of a bright burst from SGR 1935+2154 on 2020-05-10 at 06:12 UT
  47. FRB/X-ray bursts from SGR 1935+2154: No Neutrino Counterpart in ANTARES data
  48. Swift Detection of a burst from SGR Swift J1818.0-1607
  49. Insight-HXMT detection of a short bright burst from SGR 1935+2154
  50. AGILE detection of a short and hard X-ray burst possibly related to SGR 1935+2154
  51. Geocentric time correction for Insight-HXMT detection of the x-ray counterpart of the FRB by CHIME and STARE2 from SGR 1935+2154
  52. Insight-HXMT X-ray and hard X-ray upper limits to the radio burst detected by FAST from SGR 1935+2154
  53. No optical bursts detected from SGR J1935+2154 by 24 fps observations with Tomo-e Gozen
  54. Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
  55. Fermi GBM observation of a flare from the magnetar SGR 1806-20
  56. Trigger 968731: Swift detection of SGR1806-20
  57. Fermi GBM trigger 200429866/609886052 is not a GRB
  58. SGR 1935+2154: MASTER optical observations
  59. Konus-Wind observation of hard X-ray counterpart of the radio burst from SGR 1935+2154
  60. SGR 1935+2154: INTEGRAL hard X-ray counterpart of radio burst
  61. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  62. A Forest of Bursts from SGR 1935+2154
  63. SGR 1935+2154: AstroSat CZTI detections
  64. high bursting activity of SGR 1935+2154: CGBM observations
  65. SGR 1935+2154 the Insight-HXMT observation plan
  66. SGR 1935+2154: MAXI/GSC detection
  67. Fermi GBM observation of a bright flare from magnetar SGR 1935+2154
  68. Swift detection of multiple bursts from SGR 1935+2154
  69. Konus-Wind observation of a bright burst from SGR 1935+2154
  70. GRB 200415A (possible magnetar Giant Flare in Sculptor Galaxy): INTEGRAL observations
  71. IPN Triangulation of a bright burst from SGR 1935+2154
  72. bright SGR burst detected by CALET Gamma-Ray Burst Monitor
  73. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  74. Konus-Wind observation of a bright burst from SGR 1935+2154
  75. SGR 1935+2154: Fermi GBM observation
  76. IPN Triangulation of a bright burst from SGR 1935+2154
  77. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  78. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  79. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  80. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  81. Konus-Wind observation of the recent SGR 1935+2154 activity
  82. Swift trigger 933276 MASTER observation
  83. Trigger 933285: Swift detection of the brightest burst so far from SGR 1935+2154
  84. Trigger 933276: Swift detection of further activity from SGR 1935+2154
  85. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  86. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  87. SGR 1935+2154: Swift-BAT refined analysis
  88. GRB 191104B/GRB 191104C are SGR 1935+2154
  89. Trigger 933083: Swift detection of SGR 1935+2154
  90. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  91. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  92. Fermi trigger No 588801358 Global MASTER-Net observations report
  93. GRB 190326A: Swift XRT and UVOT follow-up observations
  94. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  95. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  96. Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
  97. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  98. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  99. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  100. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552

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