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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"

613 results found.

  1. IPN Triangulation of a bright burst from SGR 1935+2154
  2. bright SGR burst detected by CALET Gamma-Ray Burst Monitor
  3. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  4. Konus-Wind observation of a bright burst from SGR 1935+2154
  5. SGR 1935+2154: Fermi GBM observation
  6. IPN Triangulation of a bright burst from SGR 1935+2154
  7. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  8. SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
  9. Swift-BAT trigger 960986: Swift detection of a new SGR Swift J1818.0-1607
  10. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  11. Konus-Wind observation of the recent SGR 1935+2154 activity
  12. Swift trigger 933276 MASTER observation
  13. Trigger 933285: Swift detection of the brightest burst so far from SGR 1935+2154
  14. Trigger 933276: Swift detection of further activity from SGR 1935+2154
  15. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  16. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  17. SGR 1935+2154: Swift-BAT refined analysis
  18. GRB 191104B/GRB 191104C are SGR 1935+2154
  19. Trigger 933083: Swift detection of SGR 1935+2154
  20. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  21. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  22. Swift GRB190613.17 Global MASTER-Net observations report
  23. GRB 190326A: Swift XRT and UVOT follow-up observations
  24. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
  25. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  26. Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
  27. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  28. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  29. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  30. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  31. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  32. GRB 170524A: Swift detection of a burst (or possible new SGR)
  33. GRB 160821B: Swift-BAT refined analysis
  34. GBM observation of SGR-like burst from the direction of PSR 1119-6127
  35. Trigger 706396: Swift detection of a short burst from PSR 1119-6127
  36. GRB 160703, GRB 160705, GRB 160720, SGR1935+2154: First SGRs and GRBs detected by Lomonosov.
  37. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  38. Konus-Wind observation of a bright burst from SGR 1935+2154
  39. SGR 1935+2154: AMI 15 GHz upper limits of the magnetar during outburst
  40. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  41. Swift-BAT refined analysis on the bright event from SGR 1935+2154
  42. Trigger 701590: Swift detection of a bright outburst from SGR 1935+2154
  43. GROND observations of GRB 160622A/SNR RCW 103/SGR 1617-5103
  44. Trigger 701182: Swift detection of SGR 1935+2154
  45. SGR 1617-5103 (BAT trigger 700791): Enhanced Swift-XRT position.
  46. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  47. Fermi GBM Trigger 160622573 is not a GRB
  48. GRB 160622A: Swift detection of a possible short GRB or a new SGR
  49. More FERMI GBM bursts from the magnetar SGR 1935+2154
  50. SGR 1935+2154: MAXI/GSC detection
  51. Fermi GBM trigger 488128598/160620637 is not a GRB
  52. Fermi GBM trigger 487974449/160618852 is not a GRB
  53. Trigger 689353 (possible transient near Sgr A*), Swift-BAT refined analysis
  54. Trigger 689353: Swift detection of a transient near Sgr A*
  55. Fermi GBM trigger 486562774/160602514 is not a GRB
  56. Another Swift detection of SGR 1935+2154 (trigger #687124)
  57. Swift detection of SGR 1935+2154
  58. Konus-Wind observation of a bright burst from SGR 1935+2154
  59. FERMI GBM bursts from the magnetar SGR 1935+2154
  60. SGR 1935+2154: AbAO optical upper limit
  61. Fermi GBM triggers of SGR 1935+2154
  62. Trigger 686761: Swift detection of a bright burst from SGR 1935+2154
  63. Fermi GBM trigger 485124591/160516868 is not a GRB
  64. Trigger 686443: Swift detection of SGR 1935+2154
  65. Fermi GBM trigger 484906918/160514349 is not a GRB
  66. SGR 0755-2933, Swift-BAT refined analysis
  67. Swift detection of a likely new SGR: SGR 0755-2933
  68. IBAS Alert 7313 is SGR J1935+2154
  69. GRB 151221A: INTEGRAL detection of a short burst or possible SGR
  70. Swift-BAT refined analysis of trigger 664624 from SGR J1819-1600
  71. Swift-BAT probable detection of an outburst from SGR J1819-1600 (AX J1818.8-1559)
  72. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  73. Trigger 649113: Swift detection of SGR 1E 1841-045
  74. Swift-XRT observations of GRB 150710A
  75. Konus-Wind observation of a bright burst from SGR 1935+2154
  76. IPN Triangulation of a bright burst from SGR 1935+2154
  77. GRB 150301A: Swift-BAT refined analysis
  78. GRB 150301A: Fermi GBM observation
  79. GRB 150301A: Swift detection of a short burst or new SGR
  80. Fermi GBM Observations of SGR 1935+2154
  81. Fermi GBM trigger 150223068 is not a GRB
  82. SGR 1935+2154: Swift-BAT refined analysis
  83. Swift detection of an outburst from SGR 1935+2154
  84. Trigger 607399: Swift detection of SGR1806-20
  85. Fermi GBM Observations of SGR 1935+2154
  86. GRB 140705A / SGR 1935+2154: VLA 6 GHz observations
  87. Pre-discovery observations of SGR 1935+2154 in Swift archival data
  88. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  89. SGR 1935+2154: Swift-BAT observations of additional short soft events
  90. GRB 140705A / SGR 1935+2154: FTN observations
  91. GRB 140705A / SGR 1935+2154: Optical observations from 10.4m GTC
  92. GRB 140705A: Swift-BAT refined analysis of a possible newly discovered SGR 1935+2154
  93. Fermi GBM Trigger 140429551 - Detection of a burst from SGR 1806-20
  94. Trigger 597570: Swift detection of SGR 1806-20
  95. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  96. INTEGRAL detection of a SGR-like burst likely from SGR J1745-29
  97. Fermi/GBM Detection of two SGR-like bursts possibly associated with SGR J1833-0832
  98. SGR 1745-29 (Swift trigger 565443), Swift-BAT refined analysis
  99. Trigger 565443: Swift detection of a burst from SGR J1745-29
  100. Fermi/GBM observation of the Soft Gamma Repeater SGR J1550-5418

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