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"

11519 results found.

  1. GRB 200412B: MITSuME Akeno optical observation
  2. GRB 200412B: Tautenburg observations
  3. GRB 200412B: contunued AbAO optical observations
  4. GRB 200411A: ATCA 5/9 GHz radio observations
  5. GRB 200412B: CALET Gamma-Ray Burst Monitor detection
  6. GRB 200412B: Xinglong TNT optical observations
  7. GRB 200412B: SAO RAS observations of OT
  8. GRB 200412B: Tautenburg observations
  9. GRB 200412B: AbAO optical observations
  10. GRB 200412B: Insight-HXMT/HE detection
  11. GRB 200412B: Optical afterglow detection with 1.3m DFOT
  12. GRB 200412B : AstroSat CZTI detection
  13. GRB 200412B: Swift-XRT afterglow detection
  14. IPN triangulation of GRB 200412A
  15. Fermi GRB 200412A: Global MASTER-Net observations report
  16. GRB 200412B: Fermi GBM detection
  17. GRB 200412B: Fermi-LAT detection
  18. GRB 200412B: MASTER Optical Couterpart in Gagarin day!
  19. Konus-Wind observation of a bright burst from SGR 1935+2154
  20. GRB 200412B: Tiled Swift observations
  21. GRB 200412A: Fermi GBM detection
  22. Fermi GRB 200412B: Global MASTER-Net observations report
  23. GRB 200412B: BALROG localization (Fermi Trigger 608375325 / GRB 200412381)
  24. GRB 200412B: Fermi GBM Final Real-time Localization
  25. GRB 200412A: BALROG localization (Fermi Trigger 608367436 / GRB 200412290)
  26. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  27. GRB 200411A: Fermi GBM observation
  28. IceCube-200410A: Upper limits from Fermi-GBM Observations
  29. GRB 200411A: Fermi GBM Final Real-time Localization
  30. IceCube-200410A - IceCube observation of a high-energy neutrino candidate event
  31. SGR 1935+2154: Fermi GBM observation
  32. Fermi trigger No 608204639: Global MASTER-Net observations report
  33. IPN Triangulation of a bright burst from SGR 1935+2154
  34. Konus-Wind observation of GRB 200327A
  35. Fermi GBM Sub-Threshold Detection of GRB 200409A
  36. Fermi GRB 200407A: Global MASTER-Net observations report
  37. Fermi GRB 200407B: Global MASTER-Net observations report
  38. IPN triangulation of GRB 200407A (short)
  39. GRB 200407B: Fermi GBM Final Real-time Localization
  40. GRB 200407A: Fermi GBM Final Real-time Localization
  41. Fermi GRB 200405A: Global MASTER-Net observations report
  42. GRB 200405A: Fermi GBM Final Real-time Localization
  43. GRB 200404A: Fermi GBM Final Localization
  44. Fermi GRB 200403C: Global MASTER-Net observations report
  45. GRB 200404A: BALROG localization (Fermi Trigger 607712227 / GRB 200404706)
  46. GRB 200403A: AstroSat CZTI detection
  47. Fermi GRB 200403B: Global MASTER-Net observations report
  48. Fermi GRB 200403A: Global MASTER-Net observations report
  49. GRB 200403C: Fermi GBM Final Real-time Localization
  50. GRB 200403B: Fermi GBM Final Real-time Localization
  51. GRB 200403A: Fermi GBM Final Real-time Localization
  52. GRB 200325B: Mondy continued observations
  53. Fermi GRB 200402C: Global MASTER-Net observations report
  54. GRB 200402C: Fermi GBM Final Localization
  55. GRB 200402B: Fermi GBM Final Localization
  56. Fermi trigger No 607537834: Global MASTER-Net observations report
  57. GRB 200402B: BALROG localization (Fermi Trigger 607537834 / GRB 200402688)
  58. Fermi GRB 200402A: Global MASTER-Net observations report
  59. GRB 200402A: BALROG localization (Fermi Trigger 607513182 / GRB 200402403)
  60. GRB 200325B: Optical upper limit
  61. GRB 200402A: Fermi GBM Final Real-time Localization
  62. GRB 200325B: further Swift-XRT observations
  63. Fermi GRB 200401A: Global MASTER-Net observations report
  64. GRB 200401A: Fermi GBM Final Real-time Localization
  65. GRB 200325B: Mondy continued observations
  66. GRB 200325B: Mondy continued observations
  67. GRB 200327A: Fermi GBM detection
  68. GRB 200325B: Mondy continued observations
  69. GRB 200325B: Tautenburg observations
  70. IPN triangulation of GRB 200327A (short)
  71. GRB 200327A: AGILE/MCAL observations
  72. GRB 200325B: Fermi GBM observation
  73. Fermi trigger No 607035413: Global MASTER-Net observations report
  74. GRB 200327A: Fermi GBM Final Real-time Localization
  75. GRB 200325B: Swift-XRT and UVOT observations
  76. GRB 200325B: LCO Optical Detection
  77. GRB 200325B: Mondy, CrAO, AbAO afterglow confirmation and refined photometry of MASTER OT J111012.51+274912.8
  78. GRB 200325A: Fermi GBM observation
  79. GRB 200325B: Mondy and CrAO observations, Master MASTER OT J111012.51+274912.8 confirmation
  80. Fermi trigger No 606918292: Global MASTER-Net observations report
  81. GRB 200325B: Swift ToO observations
  82. IPN triangulation of GRB 200325A (short)
  83. Fermi trigger No 606799116: Global MASTER-Net observations report
  84. GRB 200326A: Fermi GBM Final Real-time Localization
  85. GRB 200325B: MASTERt OT detection
  86. GRB 200325A: Swift/BAT detection and probable arcminute localization of a short GRB from GUANO
  87. Fermi trigger No 606840801: Global MASTER-Net observations report
  88. GRB 200325B: Fermi GBM Final Real-time Localization
  89. GRB 200325A: AstroSat CZTI detection
  90. GRB 200325A: AGILE/MCAL observations
  91. GRB 200325A: Fermi GBM Final Real-time Localization
  92. GRB 200318A : AstroSat CZTI detection
  93. GRB 200317A: AstroSat CZTI detection
  94. Fermi trigger No 606681997: Global MASTER-Net observations report
  95. GRB 200323A: Fermi GBM detection
  96. GRB 200323A: Fermi GBM Final Real-time Localization
  97. Fermi trigger No 606614927: Global MASTER-Net observations report
  98. GRB 200320A: Fermi GBM Final Localization
  99. GRB 200319A: BALROG localization (Fermi Trigger 606296685 / GRB 200319323)
  100. GRB 200319A: 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