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"

868 results found.

  1. IPN triangulation of GRB 240810A (short)
  2. GRB 240807B: AstroSat CZTI detection of a short burst
  3. Improved IPN triangulation of GRB 240802A / EP 240802a
  4. GRB 240805A: Swift/UVOT Upper Limits
  5. IPN triangulation of GRB 240715A (short)
  6. GRB 240712A: Swift detection of a burst
  7. IPN triangulation of GRB 240627A
  8. IPN triangulation of GRB 240619C
  9. IPN triangulation of GRB 240615A (short)
  10. GRB 240615A: Fermi GBM Observation
  11. IPN triangulation of GRB 240607A
  12. IPN triangulation of GRB 240603A
  13. IPN triangulation of the initial episode of GRB 240529A
  14. IPN triangulation of GRB 240504A
  15. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  16. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  17. GRB 240415A: Prompt Swift-XRT observations
  18. IPN triangulation of GRB 240410A
  19. X-ray transient EP240315a: second epoch e-MERLIN radio observations
  20. Fermi trigger No 731303574: Global MASTER-Net observations report
  21. IPN triangulation of GRB 240303B
  22. IPN triangulation of GRB 240125A (short)
  23. IPN triangulation of GRB 240123C (short)
  24. IPN triangulation of GRB 240112A (long)
  25. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  26. LIGO/Virgo/KAGRA S231213ap: Identification of a GW compact binary merger candidate
  27. IPN triangulation of GRB 231129C
  28. IPN triangulation of GRB 231205A
  29. LIGO/Virgo/KAGRA S231206cc: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S231206ca: Identification of a GW compact binary merger candidate
  31. GRB 231205B: Ondrejov D50 optical upper limit
  32. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  33. LIGO/Virgo/KAGRA S231127cg: Identification of a GW compact binary merger candidate
  34. Konus-Wind detection of GRB 231020A
  35. 231118A: Swift-UVOT Detection
  36. LIGO/Virgo/KAGRA S231119u: Identification of a GW compact binary merger candidate
  37. GRB 231118A: Las Cumbres optical detection
  38. LIGO/Virgo/KAGRA S231118an: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S231118ab: Identification of a GW compact binary merger candidate
  40. LIGO/Virgo/KAGRA S231118d: Identification of a GW compact binary merger candidate
  41. GRB 231117A: Swift detection of a bright short burst
  42. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  43. LIGO/Virgo/KAGRA S231114n: Identification of a GW compact binary merger candidate
  44. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  45. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  47. LIGO/Virgo/KAGRA S231108u: Identification of a GW compact binary merger candidate
  48. LIGO/Virgo/KAGRA S231104ac: Identification of a GW compact binary merger candidate
  49. LIGO/Virgo/KAGRA S231102w: Identification of a GW compact binary merger candidate
  50. IPN triangulation of GRB 231020A
  51. LIGO/Virgo/KAGRA S231028bg: Identification of a GW compact binary merger candidate
  52. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  53. GRB 230911C: ATCA detection of possible radio counterpart
  54. GRB 231017A: Las Cumbres optical upper limit
  55. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  56. LIGO/Virgo/KAGRA S231005ah: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S231001aq: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S230928cb: Identification of a GW compact binary merger candidate
  59. LIGO/Virgo/KAGRA S230927be: Identification of a GW compact binary merger candidate
  60. LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate
  61. LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate
  62. IPN triangulation of GRB 230919A (short)
  63. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S230914ak: Identification of a GW compact binary merger candidate
  66. IPN triangulation of GRB 230911D (long)
  67. IPN triangulation of GRB 230906A (short)
  68. LIGO/Virgo/KAGRA S230904n: Identification of a GW compact binary merger candidate
  69. LIGO/Virgo/KAGRA S230831e: Identification of a GW compact binary merger candidate
  70. LIGO/Virgo/KAGRA S230814ah: Updated Sky localization
  71. LIGO/Virgo/KAGRA S230824r: Identification of a GW compact binary merger candidate
  72. GRB 230812B: AstroSat LAXPC detection
  73. LIGO/Virgo/KAGRA S230820bq: Identification of a GW compact binary merger candidate
  74. LIGO/Virgo/KAGRA S230819ax: Identification of a GW compact binary merger candidate
  75. Swift GRB230818.98: Global MASTER-Net observations report
  76. IPN triangulation of GRB 230815B
  77. LIGO/Virgo/KAGRA S230814r: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo/KAGRA S230811n: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S230807f: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S230806ak: Identification of a GW compact binary merger candidate
  81. LIGO/Virgo/KAGRA S230805x: Identification of a GW compact binary merger candidate
  82. IPN triangulation of GRB 230803A
  83. LIGO/Virgo/KAGRA S230731an: Identification of a GW compact binary merger candidate
  84. GRB 230723B: MITSuME Ishigaki optical observation
  85. IPN triangulation of GRB 230723A (short)
  86. LIGO/Virgo/KAGRA S230723ac: Identification of a GW compact binary merger candidate
  87. IPN triangulation of GRB 230715D
  88. LIGO/Virgo/KAGRA S230709bi: Identification of a GW compact binary merger candidate
  89. LIGO/Virgo/KAGRA S230708cf: Identification of a GW compact binary merger candidate
  90. LIGO/Virgo/KAGRA S230707ai: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S230706ah: Identification of a GW compact binary merger candidate
  92. LIGO/Virgo/KAGRA S230702an: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S230630bq: Identification of a GW compact binary merger candidate
  94. IPN triangulation of GRB 230625B (ultra-long)
  95. LIGO/Virgo/KAGRA S230628ax: Identification of a GW compact binary merger candidate
  96. LIGO/Virgo/KAGRA S230627c: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S230624av: Identification of a GW compact binary merger candidate
  98. GRB 230622A: Swift-XRT refined Analysis
  99. IPN triangulation of GRB 230616A (short)
  100. GRB 230614C: AstroSat CZTI detection

Advanced

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