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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"

827 results found.

  1. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  2. GRB 190404C: Swift-XRT observations
  3. GRB190404C: GROWTH-India discovery of optical counterpart
  4. GRB 190404B: Tiled Swift observations
  5. GRB 140404C: MAXI/GSC detection
  6. GRB 140404B: MAXI/GSC detection
  7. GRB190305A: MASTER Global Robotic Net optical observation
  8. GRB 190305A: Swift-XRT afterglow detection
  9. GRB 190305A: CALET Gamma-Ray Burst Monitor detection
  10. GRB 190306A: Swift-XRT observations
  11. Konus-Wind observation of GRB 190305A
  12. GRB 190306A: Tiled Swift observations
  13. GRB 190306A: MAXI/GSC detection
  14. IPN Triangulation of GRB 190305A
  15. GRB 190305A: Swift-XRT observations
  16. GRB 190305A: Insight-HXMT/HE detection
  17. GRB 190305A: MAXI/GSC detection
  18. Trigger 890732: Swift detection of MAXI J1631-479
  19. Trigger 888312: Swift detection of 4U 1901+03
  20. GRB 190204A: CALET Gamma-Ray Burst Monitor detection
  21. Konus-Wind observation of GRB 190204A
  22. GRB 190204A: AstroSat CZTI detection
  23. GRB 190204A: MAXI/GSC detection
  24. Fermi GBM trigger 570825115/190202772 is not a GRB
  25. Fermi GBM trigger 570716645/190201517 is not a GRB
  26. Fermi GBM trigger 570659556/190131856 is not a GRB
  27. GRB 190129A: CALET Gamma-Ray Burst Monitor detection
  28. GRB 190129A: Fermi GBM detection
  29. GRB 190129A: MAXI/GSC detection
  30. Trigger 886496: Another Swift trigger on MAXI J1348-630
  31. Trigger 886486: Swift detection of MAXI J1631-479
  32. Trigger 886266: Another Swift trigger on MAXI J1348-630
  33. INTEGRAL triggers from 8205 to 8211 are due to MAXI J1348-630, NOT to a GRB
  34. Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
  35. Trigger 885845: A second Swift trigger on MAXI J1348-630
  36. Trigger 885807: Swift detection of MAXI J1348-630
  37. Trigger 885456: Swift detection of MAXI J1631-479
  38. Trigger 884906: Swift detection of MAXI J1631-479
  39. Trigger 882561: Swift detection of MAXI J1631-479
  40. GRB 181228A: KAIT Optical Upper Limit
  41. GRB 181222A: AstroSat CZTI detection
  42. Konus-Wind observation of GRB 181222A
  43. GRB 181222A: CALET Gamma-Ray Burst Monitor detection
  44. GRB 181222A: Fermi GBM observation
  45. GRB 181222A: MAXI/GSC detection
  46. GRB 181011A: MITSuME Akeno and Okayama optical upper limits
  47. GRB 181011A: Global MASTER Net optical inspection
  48. GRB 181011A: CALET Gamma-Ray Burst Monitor detection
  49. IPN Triangulation of GRB 181011A (long)
  50. GRB 181011A: MAXI/GSC detection
  51. Konus-Wind observation of GRB 180923A
  52. GRB 180923B - GBM Correction to GCN 23263
  53. GRB 180923A: CALET Gamma-Ray Burst Monitor detection
  54. GRB 180923A: MASTER inspection MAXI/GSC error box
  55. GRB 180923A: MAXI/GSC detection
  56. GRB 180829A: Swift-XRT observations
  57. GRB 180829A: Tiled Swift observations
  58. GRB 180829A/MAXI J0406-019: MAXI/GSC detection
  59. GRB 180809A: further Swift/XRT observations
  60. GRB 180809A: Fermi GBM observation
  61. GRB 180809A: CALET Gamma-Ray Burst Monitor detection
  62. GRB 180809A: Swift-XRT afterglow detection
  63. GRB 180809A: Tiled Swift observations
  64. GRB 180809A: MAXI/GSC detection
  65. GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
  66. GRB 180720B: CALET Gamma-Ray Burst Monitor detection
  67. GRB 180722A: Swift-XRT observations
  68. GRB 180722A: MASTER second inspection
  69. GRB 180720B: MASTER Global Net OT observations
  70. GRB 180720B: ISON-Castelgrande optical observations
  71. GRB 180722A: Tiled Swift observations
  72. GRB 180722A: MASTER optical observation
  73. GRB 180722A: MAXI/GSC detection
  74. GRB 180720B: MAXI/GSC detection
  75. GRB 180706A: Swift/UVOT Detection
  76. Konus-Wind observation of GRB 180701A
  77. GRB 180701A: MAXI/GSC detection
  78. GW170817/GRB170817A: LBT optical detection
  79. Swift trigger 831888: misidentification of 4U 1416-62
  80. Fermi GBM triggers 544628550/180405571, 544542853/180404579, 544531428/180404447 are not GRBs
  81. Fermi GBM triggers 544440014/180403389 and 544451446/180403521 are not GRBs
  82. GRB 180402A, Swift-BAT refined analysis
  83. GRB 180402A: Swift detection of a possibly short burst
  84. Swift Trigger 819301: possible GRB 180329A
  85. Konus-Wind observation of GRB 180326A
  86. IBAS Alert n. 8033: Not a GRB
  87. IBAS Alert n. 8032: Not a GRB
  88. Swift Trigger on MAXI J1820+070
  89. Trigger 814090: Swift detection of MAXI J1820+070
  90. MAXI J1820+070: Swift/UVOT counterpart correction
  91. Swift detection of MAXI J1820+070
  92. MAXI J1813-095 source: AbAO optical observations
  93. Swift Trigger 811167: Detection of MAXI J1813-095
  94. GRB 180116A: Fermi GBM Detection
  95. GRB 180116A: MAXI/GSC detection
  96. GRB 171216A: Swift/UVOT Upper Limits
  97. GRB 171112A: Fermi GBM Detection
  98. Konus-Wind observation of GRB 171112A
  99. GRB 171112A: MAXI/GSC detection
  100. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552

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