Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

11559 results found.

  1. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  2. GRB 241025A: SVOM/GRM observation
  3. GRB 241025A: TRT optical afterglow observation
  4. Fermi GRB 241024B: Global MASTER-Net observations report
  5. GRB 241025A: Fermi GBM Final Real-time Localization
  6. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  7. GRB 241024B: Fermi GBM Final Localization
  8. EP241021a: No Detection in Fermi-GBM Observation
  9. GRB 241024A: Fermi GBM Final Localisation
  10. Fermi trigger No 751449953: Global MASTER-Net observations report
  11. GRB 241018A: REM optical/NIR upper limits
  12. GRB 241016B: Fermi GBM Observations
  13. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  14. Fermi trigger No 750788395: Global MASTER-Net observations report
  15. GRB 241016B: SVOM/GRM observation
  16. GRB241016C: Fermi GBM Final Localization
  17. Fermi Gamma-ray Burst Monitor trigger 750792698/241016730 is not a GRB
  18. Fermi GRB 241016B: Global MASTER-Net observations report
  19. GRB 241016B: Fermi GBM Final Localization
  20. Fermi GRB 241016A: Global MASTER-Net observations report
  21. GRB 241016A: Fermi GBM Final Real-time Localization
  22. GRB 241013B: Fermi GBM Observation
  23. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  24. GRB 241013A: Fermi GBM Observation
  25. GRB 240916A: radio detection with the VLA
  26. GRB241013A: REM observations
  27. GRB 241013B: SVOM/GRM observation
  28. Fermi GRB 241013B: Global MASTER-Net observations report
  29. GRB 241013B: Fermi GBM Final Real-time Localization
  30. GRB 241013A: a long GRB detected by INTEGRAL
  31. GRB 241013A: Fermi GBM Final Real-time Localization
  32. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  33. GRB 241011A: Fermi GBM Final Real-time Localization
  34. Fermi trigger No 750211959: Global MASTER-Net observations report
  35. Fermi Gamma-ray Burst Monitor trigger 750303285/241011066 is not a GRB
  36. Fermi Gamma-ray Burst Monitor trigger 750291012/241010924 is not a GRB
  37. Fermi trigger No 750291012: Global MASTER-Net observations report
  38. Fermi GRB 241010B: Global MASTER-Net observations report
  39. GRB 241010B: Fermi GBM Final Real-time Localization
  40. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  41. GRB 241008A: Fermi GBM Observation
  42. GRB 241008A: Fermi-LAT detection
  43. GRB 241002B: Swift-XRT afterglow detection
  44. Fermi GRB 241008A: Global MASTER-Net observations report
  45. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  46. GRB 241008A: Fermi GBM Final Real-time Localization
  47. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  48. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  49. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  50. IceCube-241006A - IceCube observation of a high-energy neutrino candidate track-like event
  51. GRB 240930B: SVOM/C-GFT optical upper limit
  52. Fermi trigger No 749721670: Global MASTER-Net observations report
  53. GRB 240930B / EP 240930a: SVOM/GRM observation
  54. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  55. GRB 241002B: Fermi GBM Observation
  56. Fermi trigger No 749735279: Global MASTER-Net observations report
  57. Fermi trigger No 749630753: Global MASTER-Net observations report
  58. Fermi trigger No 749693019: Global MASTER-Net observations report
  59. GRB 241002B: Swift-XRT observations
  60. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  61. GRB 241002B: Swift ToO observations
  62. GRB 241002B: PRIME near-infrared detection
  63. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  64. IPN triangulation of GRB 240930B / EP 240930a
  65. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  66. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  67. GRB 240930B: CALET Gamma-Ray Burst Monitor detection
  68. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  69. EP240930a: Liverpool Telescope observations
  70. GRB 241002B: GOTO optical counterpart candidate
  71. GRB 240929A: Liverpool Telescope prompt followup observations
  72. Fermi GRB 241002B: Global MASTER-Net observations report
  73. GRB 241002B: Fermi GBM Final Real-time Localization
  74. GRB 240930B: Fermi GBM Observation
  75. GRB 240930B: GRBAlpha detection
  76. GRB 240929A: GRBAlpha detection
  77. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  78. EP240930a: EP-FXT follow-up observation update
  79. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  80. EP240930a: GOTO optical upper limits
  81. GRB 240929A: SVOM/GRM observation
  82. EP240930a: EP-WXT detection of a fast X-ray transient
  83. GRB 240929A : Leavitt Observatory optical upper limit
  84. Fermi GRB 240930B: Global MASTER-Net observations report
  85. GRB 240930B: Fermi GBM Final Real-time Localization
  86. GRB 240825A: LBT optical observations
  87. Fermi GRB 240930A: Global MASTER-Net observations report
  88. Fermi Gamma-ray Burst Monitor trigger 749362078/240930172 (GRB 240930A) is not a GRB
  89. GRB 240930A: Fermi GBM Final Real-time Localization
  90. Fermi trigger No 749339671: Global MASTER-Net observations report
  91. Fermi Gamma-ray Burst Monitor trigger 749339671/240929913 is not a GRB
  92. GRB 240929A long GRB detected by INTEGRAL
  93. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  94. Fermi GRB 240929A: Global MASTER-Net observations report
  95. GRB 240929A: Fermi GBM Final Real-time Localization
  96. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  97. Konus-Wind detection of GRB 240912A
  98. Fermi Gamma-ray Burst Monitor trigger 749191601/240928199 is not a GRB
  99. Konus-Wind detection of GRB 240905B
  100. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73

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