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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"

11111 results found.

  1. Fermi trigger No 586676451 Global MASTER-Net observations report
  2. GRB 190805B: Fermi GBM detection
  3. Konus-Wind observation of GRB 190731A
  4. GRB 190805B: BALROG localization (Fermi Trigger 586673165 / GRB 190805199)
  5. GRB 190805B: MAXI/GSC detection
  6. GRB 190805B: Fermi GBM Final Real-time Localization
  7. GRB 190805A: Fermi GBM Final Real-time Localization
  8. Fermi trigger No 586638042 Global MASTER-Net observations report
  9. Fermi trigger No 586600841 Global MASTER-Net observations report
  10. GRB 190804C: BALROG localization (Fermi Trigger 586638042 / GRB 190804792)
  11. GRB 190804C: Fermi GBM Final Real-time Localization
  12. Fermi trigger No 586574612 Global MASTER-Net observations report
  13. GRB 190804A: Fermi GBM Final Real-time Localization
  14. GRB 190731A: AstroSat CZTI detection
  15. GRB 190731A: no OT detected by MASTER
  16. GRB 190720B: AstroSat CZTI detection
  17. GRB 190731A: Swift-XRT afterglow detection
  18. IPN Triangulation of GRB 190731A
  19. GRB 190731A: Fermi GBM detection
  20. GRB 190726B: AstroSat CZTI detection
  21. GRB 190731A: CALET Gamma-Ray Burst Monitor detection
  22. GRB 190731A: Swift ToO observations
  23. GRB190731A: Fermi-LAT detection
  24. Fermi trigger No 586305505 Global MASTER-Net observations report
  25. Fermi trigger No 586305505 Global MASTER-Net observations report
  26. GRB 190731A: Fermi GBM Final Real-time Localization
  27. Fermi-LAT Gamma-ray Observations of IceCube-190730A
  28. Fermi trigger No 586240252 Global MASTER-Net observations report
  29. IceCube 190730A: not observable by Fermi-GBM
  30. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  31. Fermi Gamma-ray Burst Monitor trigger 190729668/586108936 is not a GRB
  32. Konus-Wind observation of GRB 190727B
  33. IPN triangulation of GRB 190728A (short)
  34. LIGO/Virgo S190728q: No counterpart candidates in Fermi-LAT observations
  35. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  36. GRB 190727B: Fermi-LAT detection
  37. Fermi trigger No 585988241 Global MASTER-Net observations report
  38. GRB 190728A: Fermi GBM Final Real-time Localization
  39. GRB 190727B: Fermi GBM observations
  40. GRB 190727B: BALROG localization (Fermi Trigger 585951481 / GRB 190727846)
  41. GRB 190727B: Fermi GBM Final Real-time Localization
  42. GRB 190727A: BALROG localization (Fermi Trigger 585936117 / GRB 190727668)
  43. GRB 190727A: Fermi GBM Final Real-time Localization
  44. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  45. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  46. Fermi trigger No 585864875 Global MASTER-Net observations report
  47. Fermi trigger No 585847498 Global MASTER-Net observations report
  48. GRB 190726B: BALROG localization (Fermi Trigger 585864875 / GRB 190726843)
  49. GRB 190726B: Fermi GBM Final Real-time Localization
  50. Fermi trigger No 585856427 Global MASTER-Net observations report
  51. GRB 190726A: BALROG localization (Fermi Trigger 585847498 / GRB 190726642)
  52. GRB 190726A: Fermi GBM Final Real-time Localization
  53. GRB 190724A: Insight-HXMT/HE detection
  54. GRB 190723A: Insight-HXMT/HE detection
  55. GRB 190720A: CALET Gamma-Ray Burst Monitor detection
  56. IPN triangulation of GRB 190724A (short)
  57. Fermi trigger No 585621841 Global MASTER-Net observations report
  58. GRB 190724A: Fermi GBM Final Real-time Localization
  59. Fermi trigger No 585559462 Global MASTER-Net observations report
  60. GRB 190723A: Fermi GBM Final Real-time Localization
  61. IPN triangulation of GRB 190720A
  62. GRB 190720B: Insight-HXMT/HE detection
  63. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  64. GRB 190720B: Fermi GBM Final Real-time Localization
  65. GRB 190720A: Fermi GBM detection
  66. GRB 190719C: Fermi GBM detection
  67. GRB 190720A: BALROG localization (Fermi Trigger 585326534 / GRB 190720613)
  68. GRB 190720A: Fermi GBM Final Real-time Localization
  69. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  70. Fermi trigger No 585196946 Global MASTER-Net observations report
  71. GRB 190719C: NOT candidate optical afterglow and host
  72. GRB 190719C: Swift detection of a burst
  73. GRB 190719C: Fermi GBM Final Real-time Localization
  74. LIGO/Virgo S190718y: No counterpart candidates in Fermi-LAT observations
  75. GRB 190719A: Fermi GBM Final Real-time Localization
  76. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  77. GRB 190613B: FRAM-Auger afterglow detection
  78. Fermi trigger No 585007213 Global MASTER-Net observations report
  79. GRB 190716A: BALROG localization (Fermi Trigger 585007213 / GRB 190716917)
  80. GRB 190716A: Fermi GBM Final Real-time Localization
  81. Fermi trigger No 584977168 Global MASTER-Net observations report
  82. Fermi trigger No 584929684 Global MASTER-Net observations report
  83. Fermi trigger No 584929684 Global MASTER-Net observations report
  84. Fermi trigger No 584804684 Global MASTER-Net observations report
  85. GRB 190714B: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 584710308 Global MASTER-Net observations report
  87. Fermi-LAT Gamma-ray Observations of IceCube-190712A
  88. Fermi trigger No 584637077 Global MASTER-Net observations report
  89. IceCube-190712A: Upper limits from Fermi-GBM Observations
  90. IceCube-190712A - IceCube observation of a high-energy neutrino candidate event
  91. Fermi trigger No 584590606 Global MASTER-Net observations report
  92. GRB 190712A: Fermi GBM Final Real-time Localization
  93. Fermi trigger No 584583925 Global MASTER-Net observations report
  94. Fermi trigger No 584465880 Global MASTER-Net observations report
  95. Fermi trigger No 584404689 Global MASTER-Net observations report
  96. IPN triangulation of GRB 190706D (short)
  97. IPN triangulation of GRB 190706C (long/very bright)
  98. Fermi trigger No 584264100 Global MASTER-Net observations report
  99. LIGO/Virgo S190707q: No counterpart candidates in Fermi-LAT observations
  100. GRB 190708A: Fermi GBM Final Real-time Localization

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