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"

1519 results found.

  1. IceCube-251218A: No Candidate Transients from the Zwicky Transient Facility
  2. Fermi-LAT Gamma-ray Observations of IceCube-251218A
  3. IceCube-251218A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-251218A: COLIBRÍ optical upper limits
  5. IceCube-251218A - IceCube observation of a high-energy neutrino candidate track-like event
  6. IceCube Alert 251218.85: Global MASTER-Net observations report
  7. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  8. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  9. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  10. IceCube-251210A: DDOTI Optical Upper Limit
  11. IceCube Alert 251210.46: Global MASTER-Net observations report
  12. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  13. Fermi-LAT Gamma-ray Observations of IceCube-251130A
  14. IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
  15. IceCube Alert 251130.75: Global MASTER-Net observations report
  16. IceCube-251130A - IceCube observation of a high-energy neutrino candidate track-like event
  17. IceCube-Cascade 251112A: Upper limits from a search for additional neutrino events in IceCube
  18. LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
  19. LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
  20. IceCube-Cascade 251107A: Upper limits from a search for additional neutrino events in IceCube
  21. IceCube-251025A: Two Transient Candidates from the Zwicky Transient Facility
  22. IceCube-251025A: Upper limits from a search for additional neutrino events in IceCube
  23. Fermi-LAT Gamma-ray Observations of IceCube-251025A
  24. IceCube-251025A: DDOTI Optical Upper Limit
  25. IceCube Alert 251025.57: Global MASTER-Net observations report
  26. IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
  27. Fermi-LAT gamma-ray observations of IceCube-251018A
  28. IceCube-251018A: Upper limits from a search for additional neutrino events in IceCube
  29. IceCube-251018A: DDOTI Optical Upper Limit
  30. IceCube-251018A: Global MASTER-Net observations report
  31. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event
  32. IceCube-251018A - IceCube observation of a high-energy neutrino candidate track-like event (duplicate submission)
  33. Upper limits from a search for additional neutrino events in IceCube
  34. IceCube Alert 251014.77: Global MASTER-Net observations report
  35. Fermi-LAT Gamma-ray Observations of IceCube-251014A
  36. IceCube-251014A - IceCube observation of a high-energy neutrino candidate track-like event
  37. IceCube alert 141456_888784 retraction
  38. IceCube Alert 251008A: Global MASTER-Net observations report
  39. Fermi-LAT Gamma-ray Observations of IceCube-250926A
  40. IceCube-250926A: Upper limits from a search for additional neutrino events in IceCube
  41. IceCube Alert 250926.52: Global MASTER-Net observations report
  42. IceCube-250926A - IceCube observation of a high-energy neutrino candidate track-like event
  43. LIGO/Virgo/KAGRA S250918aw: 1 counterpart neutrino candidate event from an IceCube neutrino search
  44. LIGO/Virgo/KAGRA S250917aq: Three counterpart neutrino candidates from IceCube neutrino searches
  45. IceCube-Cascade 250911A: Upper limits from a search for additional neutrino events in IceCube
  46. LIGO/Virgo/KAGRA S250912s: 2 counterpart neutrino candidate events from an IceCube neutrino search
  47. Fermi-LAT Gamma-ray Observations of IceCube-250905A
  48. IceCube-250905A: Upper limits from a search for additional neutrino events in IceCube
  49. IceCube-250905A - IceCube observation of a high-energy neutrino candidate track-like event
  50. IceCube Alert 250905.84: Global MASTER-Net observations report
  51. IceCube-Cascade 250903A: Upper limits from a search for additional neutrino events in IceCube
  52. Fermi-LAT Gamma-ray Observations of IceCube-250831A
  53. IceCube-250831A: Upper limits from a search for additional neutrino events in IceCube
  54. LIGO/Virgo/KAGRA S250902av: 1 counterpart neutrino candidate event from an IceCube neutrino search
  55. IceCube-Cascade 250828A: Upper limits from a search for additional neutrino events in IceCube
  56. IceCube Alert 250831.75: Global MASTER-Net observations report
  57. IceCube-250831A - IceCube observation of a high-energy neutrino candidate track-like event
  58. IceCube-250813A: Upper limits from a search for additional neutrino events in IceCube
  59. Fermi-LAT Gamma-ray Observations of IceCube-250813A
  60. IceCube-250813A - IceCube observation of a high-energy neutrino candidate track-like event
  61. IceCube Alert 250813.14: Global MASTER-Net observations report
  62. IceCube-Cascade 250809A: Upper limits from a search for additional neutrino events in IceCube
  63. Fermi-LAT Gamma-ray Observations of IceCube-250804A
  64. IceCube-250804A: Upper limits from a search for additional neutrino events in IceCube
  65. IceCube-Cascade 250804A: Upper limits from a search for additional neutrino events in IceCube
  66. IceCube Alert 250804.84: Global MASTER-Net observations report
  67. IceCube-250804A - IceCube observation of a high-energy neutrino candidate track-like event
  68. IceCube-250708A: No Candidates from WINTER
  69. IceCube-250708A: No Candidate Transients from the Zwicky Transient Facility
  70. IceCube-250708A: Upper limits from a search for additional neutrino events in IceCube
  71. IceCube-250706A: No Candidates from WINTER
  72. IceCube-250706A: No Candidates from the Zwicky Transient Facility
  73. IceCube-250708A - IceCube observation of a high-energy neutrino candidate track-like event
  74. IceCube-250708A: Global MASTER-Net observations report
  75. IceCube-250706A: Upper limits from a search for additional neutrino events in IceCube
  76. IceCube-250706A: EP-FXT follow-up observations
  77. Fermi-LAT Gamma-ray Observations of IceCube-250706A
  78. IceCube-250706A: Global MASTER-Net observations report
  79. IceCube-250416A: DDOTI Optical Upper Limit
  80. IceCube-250706A: COLIBRÍ optical upper limits
  81. IceCube-250706A - IceCube observation of a high-energy neutrino candidate track-like event
  82. IceCube alert 141029_8144692 retraction
  83. IceCube-250506A: No Transient Candidates from the Zwicky Transient Facility
  84. IceCube-250506A: Upper limits from a search for additional neutrino events in IceCube
  85. Fermi-LAT Gamma-ray Observations of IceCube-250506A
  86. IceCube-250506A - IceCube observation of a high-energy neutrino candidate track-like event
  87. IceCube Alert 250506.59: Global MASTER-Net observations report
  88. Fermi-LAT Gamma-ray Observations of IceCube-250429A
  89. IceCube-250429A: Upper limits from a search for additional neutrino events in IceCube
  90. IceCube-250426A: Upper limits from a search for additional neutrino events in IceCube
  91. IceCube-250429A - IceCube observation of a high-energy neutrino candidate track-like event
  92. Fermi-LAT Gamma-ray Observations of IceCube-250426A
  93. IceCube Alert 250426.74: Global MASTER-Net observations report
  94. IceCube-250426A - IceCube observation of a high-energy neutrino candidate track-like event (duplicate submission)
  95. IceCube-250426A - IceCube observation of a high-energy neutrino candidate track-like event
  96. IceCube-250416A: Upper limits from a search for additional neutrino events in IceCube
  97. IceCube-250421A: Upper limits from a search for additional neutrino events in IceCube
  98. Fermi-LAT gamma-ray observations of IceCube-250421A
  99. IceCube-250421A: DDOTI Detection of the LAST Candidate
  100. IC-250421A: LAST optical observations of the IceCube neutrino candidate

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov