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"

1005 results found.

  1. MAXI GRB220706.73: Global MASTER-Net observations report
  2. Trigger 1113743: Swift detection of MAXI J0655-013
  3. GRB 220624A: Fermi GBM Detection
  4. Swift Detection of MAXI J0655-013
  5. MAXI GRB220607.31: Global MASTER-Net observations report
  6. MAXI GRB220607.41: Global MASTER-Net observations report
  7. Konus-Wind detection of GRB 220506A
  8. Konus-Wind detection of GRB 220514B
  9. GRB 220514B: Swift-XRT observations
  10. GRB 220514B: Tiled Swift observations
  11. GRB 220514B: MAXI/GSC detection
  12. MAXI GRB220514.98: Global MASTER-Net observations report
  13. GRB 220506A: MITSuME Akeno optical upper limits
  14. GRB 220506A: GIT optical upper limit.
  15. GRB 220506A: BOOTES-5/JGT optical upper limit
  16. GRB 220506A: Swift-XRT afterglow detection
  17. GRB 220506A: Tiled Swift observations
  18. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  19. MAXI GRB220506.27: Global MASTER-Net observations report
  20. IceCube-220425A: MASTER: flaring blazar TXS 1742-078 as the possible neutrino source candidate
  21. GRB 220310A: MITSuME Akeno optical observation
  22. IPN triangulation of GRB 220310A
  23. GRB 220310A: [KAO-Egypt] SDSS r, i observation
  24. Konus-Wind detection of GRB 220310A
  25. GRB 220310A: GIT confirmation of optical afterglow.
  26. GRB 220310A: MASTER optical counterpart detection
  27. GRB 220310A: Swift ToO observations
  28. GRB 220310A: CALET Gamma-Ray Burst Monitor detection
  29. GRB 220310A: MAXI/GSC detection
  30. MAXI GRB220310.02: Global MASTER-Net observations report
  31. GRB 211227A: Konus-Wind detection and joint Konus-Wind+Swift-BAT spectral analysis
  32. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  33. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  34. GRB 211227A: MAXI/GSC detection
  35. GRB 211225A: MITSuME Akeno optical upper limits
  36. MAXI GRB211225.14: Global MASTER-Net observations report
  37. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  38. GRB 211218A: MITSuME Akeno optical upper limits
  39. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  40. MAXI GRB211218.04: Global MASTER-Net observations report
  41. GRB 211115A: CALET Gamma-Ray Burst Monitor detection
  42. GRB 211115A: MAXI/GSC detection
  43. Fermi GRB 210812A: Global MASTER-Net observations report
  44. MAXI GRB210709.93: Global MASTER-Net observations report
  45. GRB 210704A: AstroSat CZTI detection
  46. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  47. GRB 210607A/MAXI J1733-222: MAXI/GSC detection
  48. MAXI GRB210607.82: Global MASTER-Net observations report
  49. Konus-Wind detection of GRB 210602A
  50. MAXI GRB210602.50: Global MASTER-Net observations report
  51. GRB 210602A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 210602A: MAXI/GSC detection
  53. GRB 210528B: DDOTI Upper Limits on the Afterglow
  54. MAXI GRB210528.95: Global MASTER-Net observations report
  55. GRB 210528B: MAXI/GSC detection
  56. MAXI GRB210521.54: Global MASTER-Net observations report
  57. GRB 210521A: MAXI/GSC detection
  58. Swift Detection of MAXI J1803-298 including an optical counterpart
  59. MAXI GRB210501.83: Global MASTER-Net observations report
  60. MAXI GRB210320.89: Global MASTER-Net observations report
  61. GRB 210320A: MAXI/GSC detection
  62. Konus-Wind detection of GRB 210222A
  63. GRB 210222A: CALET Gamma-Ray Burst Monitor detection
  64. GRB 210222A: MAXI/GSC detection
  65. SGR 1935+2154: MAXI/GSC detection
  66. NuEm-210111A: MAXI/GSC upper limit
  67. MAXI GRB210110.64: Global MASTER-Net observations report
  68. GRB 210110A: MAXI/GSC detection
  69. GRB 210109A: MAXI/GSC detection
  70. GRB 210102B: further Swift-XRT observations
  71. GRB 210102B: Assy optical afterglow identification
  72. GRB 210102B: Tiled Swift observations
  73. GRB 210102B: Assy optical observations
  74. GRB 210102B: Swift-XRT observations
  75. MAXI GRB210102.38: Global MASTER-Net observations report
  76. GRB 210102B: Tiled Swift observations
  77. GRB 210102B: MAXI/GSC detection
  78. IceCube-201209A : MAXI/GSC upper limit
  79. IceCube Alert 201130.85: Global MASTER-Net observations report
  80. MAXI GRB201021.68: Global MASTER-Net observations report
  81. GRB 201021B MAXI/GSC detection
  82. Swift GRB 201017A: Global MASTER-Net observations report
  83. GRB 201014A: BOOTES-1 and -2 early optical upper limits
  84. Fermi GRB 200916A: Global MASTER-Net observations report
  85. GRB 200903D: MAXI/GSC detection
  86. GRB 200809B: Fermi GBM detection
  87. GRB 200809B: Swift-XRT afterglow detection
  88. GRB 200809B: MAXI/GSC detection
  89. GRB 200615B: CALET Gamma-Ray Burst Monitor detection
  90. GRB 200615B: MAXI/GSC detection
  91. IceCube-200615A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  92. GRB 200517A: Swift-XRT Confirmation of afterglow
  93. Fermi GBM Sub-Threshold Detection of GRB 200517A
  94. GRB 200517A: Swift-XRT afterglow detection
  95. GRB 200514A: AstroSat CZTI detection
  96. GRB 200517A: Tiled Swift observations
  97. GRB 200517A: MAXI/GSC detection
  98. GRB 200514A: MITSuME Akeno optical upper limits
  99. GRB 200514A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 200514A: MAXI/GSC 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