Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

5158 results found.

  1. IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  2. GRB 211207A: Swift-XRT refined Analysis
  3. Swift GRB 211207A: Global MASTER-Net observations report
  4. GRB 211207A: Swift detection of a burst with an optical counterpart
  5. IPN triangulation of GRB 211204C
  6. Fermi GRB 211204B: Global MASTER-Net observations report
  7. GRB 211124A: Fermi GBM Observation
  8. IPN triangulation of GRB 211130A
  9. GRB 211129A: Swift-XRT refined Analysis
  10. IceCube-211125A: Upper limits from a search for additional neutrino events in IceCube
  11. IPN triangulation of GRB 211118A
  12. GRB 211129A: MITSuME Akeno optical upper limits
  13. Konus-Wind detection of GRB 211120A
  14. Chandra observations of GRB 210905A
  15. IceCube-211123A: Upper limits from a search for additional neutrino events in IceCube
  16. IceCube Alert 211123.60: Global MASTER-Net observations report
  17. Fermi trigger No 659413798: Global MASTER-Net observations report
  18. Fermi trigger No 659183098: Global MASTER-Net observations report
  19. Fermi trigger No 658971499: Global MASTER-Net observations report
  20. IceCube-211116A: Upper limits from a search for additional neutrino events in IceCube
  21. Fermi trigger No 658755664: Global MASTER-Net observations report
  22. Konus-Wind detection of GRB 211107B
  23. Fermi trigger No 658686687: Global MASTER-Net observations report
  24. GRB 211115A: MAXI/GSC detection
  25. Fermi GRB 211112A: Global MASTER-Net observations report
  26. Fermi trigger No 658214822: Global MASTER-Net observations report
  27. Fermi GRB 211109B: Global MASTER-Net observations report
  28. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  29. GRB 211024A: MITSuME Akeno optical observation
  30. GRB 211023B: MITSuME Akeno optical upper limits
  31. GRB 211024A: 1.3m DFOT observations
  32. GRB 211024A: Fermi GBM detection
  33. IceCube-211023A: Upper limits from a search for additional neutrino events in IceCube
  34. GRB 211025A: Swift-XRT refined Analysis
  35. GRB 211024B: Swift-XRT refined Analysis
  36. GRB 211023A: 1.5m OSN optical observation
  37. GRB 211024B: Nanshan/NEXT optical afterglow detection
  38. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  39. Fermi GRB 211023A: Global MASTER-Net observations report
  40. GRB 211023B: Swift-XRT refined Analysis
  41. Fermi GRB 211024A: Global MASTER-Net observations report
  42. GRB 211024A: Fermi GBM Final Real-time Localization
  43. IceCube Alert 211023.36: Global MASTER-Net observations report
  44. Fermi trigger No 656506979: Global MASTER-Net observations report
  45. Swift trigger 1078701: MITSuME Akeno optical upper limits
  46. Fermi trigger No 655673024: Global MASTER-Net observations report
  47. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  48. Fermi trigger No 655401471: Global MASTER-Net observations report
  49. GRB 210928A: Fermi GBM observation
  50. Fermi trigger No 654739449: Global MASTER-Net observations report
  51. Swift Trigger 1076121 is not a GRB
  52. GRB 210930A: Swift-XRT refined Analysis
  53. Fermi GRB 210929B: Global MASTER-Net observations report
  54. IceCube-210922A: JCMT/SCUBA2 observations
  55. GRB 210924A: Fermi GBM Final Real-time Localization
  56. GRB 210919A: MITSuME Akeno optical upper limits
  57. GRB 210912A: Swift-XRT refined Analysis
  58. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  59. Fermi trigger No 653066776: Global MASTER-Net observations report
  60. Fermi trigger No 653084584: Global MASTER-Net observations report
  61. Fermi trigger No 653083551: Global MASTER-Net observations report
  62. Fermi trigger No 653066130: Global MASTER-Net observations report
  63. Fermi trigger No 653071808: Global MASTER-Net observations report
  64. Fermi trigger No 653049776: Global MASTER-Net observations report
  65. Fermi trigger No 653022153: Global MASTER-Net observations report
  66. Fermi trigger No 652981861: Global MASTER-Net observations report
  67. GECAM observations of a series of bursts from SGR J1935+2154
  68. Fermi trigger No 652911693: Global MASTER-Net observations report
  69. Fermi trigger No 652906639: Global MASTER-Net observations report
  70. GRB 210905A: AstroSat CZTI detection
  71. Fermi trigger No 652585475: Global MASTER-Net observations report
  72. GRB 210610A: Maidanak and AbAO optical observations
  73. Fermi GRB 210903B: Global MASTER-Net observations report
  74. GRB 210827A: Fermi GBM Observation
  75. GRB 210826A: AstroSat CZTI detection
  76. Fermi GRB 210827A: Global MASTER-Net observations report
  77. GRB 210827A: Fermi GBM Final Real-time Localization
  78. Fermi GRB 210826A: Global MASTER-Net observations report
  79. GRB 210824A: MITSuME Akeno optical upper limits
  80. GRB 210822A: TSHAO continued optical observation
  81. GRB 210822A: VLA detection
  82. Swift GRB 210824A: Global MASTER-Net observations report
  83. GRB 210824A: Fermi GBM Observation
  84. Fermi GRB 210824A: Global MASTER-Net observations report
  85. GRB 210824A: Nanshan/NEXT optical upper limit
  86. GRB 210824A: Swift-XRT refined Analysis
  87. GRB 210824A: Fermi GBM Final Real-time Localization
  88. GRB 210822A: Swift-XRT refined Analysis
  89. Fermi GRB 210822B: Global MASTER-Net observations report
  90. GRB 210822B: Fermi GBM Final Real-time Localization
  91. Swift GRB 210822A: Global MASTER-Net observations report
  92. Fermi GRB 210821A: Global MASTER-Net observations report
  93. GRB 210820A: Swift-XRT refined Analysis
  94. GRB 210818A: Swift-XRT refined Analysis
  95. Fermi GRB 210813A: Global MASTER-Net observations report
  96. GRB 210807C: Swift-BAT refined analysis
  97. GRB 210807C: Enhanced Swift-XRT position
  98. Fermi GRB 210807C: Global MASTER-Net observations report
  99. GRB 210807C: Swift detection of a burst
  100. GRB 210807C: Fermi GBM Final Real-time Localization

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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