Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
New! Super-Kamiokande JSON Notices and Schema v4.5.0. See news and announcements

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"

607 results found.

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

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov