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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"

3798 results found.

  1. Fermi trigger No 625695596: Global MASTER-Net observations report
  2. MAXI GRB201021.68: Global MASTER-Net observations report
  3. GRB 201021B MAXI/GSC detection
  4. Fermi GRB 201020B: Global MASTER-Net observations report
  5. GRB 201020A: Swift detection of a burst with an optical counterpart.
  6. Konus-Wind observation of GRB 201013A
  7. SGR 1830-0645: Swift-BAT refined analysis
  8. GRB 201006A: Chandra upper limit on the X-ray afterglow
  9. Baksan Neutrino Observatory Alert 201006.88: Global MASTER-Net observations report
  10. GRB 201006A: Swift detection of a burst
  11. Fermi trigger No 623470566: Global MASTER-Net observations report
  12. Fermi trigger No 623493962: Global MASTER-Net observations report
  13. Swift-XRT observations of IceCube 200929A
  14. GRB 200928A: Fermi GBM Final Localization
  15. Fermi GRB 200925A: Global MASTER-Net observations report
  16. GRB 200923A: Fermi GBM Final Real-time Localization
  17. GRB 200922A: Swift-BAT refined analysis
  18. Fermi GRB 200914A: Global MASTER-Net observations report
  19. Fermi GRB 200909A: Global MASTER-Net observations report
  20. GRB 200907C: Fermi GBM Final Real-time Localization
  21. GRB 200906A: EMIR/GTC NIR upper limit
  22. GRB 200906A: LBT near-infrared upper limit
  23. Fermi GRB 200903C: Global MASTER-Net observations report
  24. GRB 200903D: MAXI/GSC detection
  25. GRB 200903A: Swift-BAT refined analysis
  26. Fermi GRB 200903B: Global MASTER-Net observations report
  27. Swift GRB200903.03: Global MASTER-Net observations report
  28. GRB 200901B: Swift-BAT refined analysis
  29. GRB 200829A: Kitab optical upper limit
  30. Zwicky Transient Facility discovery of ZTF20abtxwfx/AT2020sev, a fast optical transient and candidate afterglow
  31. IPN triangulation of GRB 200826B
  32. Fermi GRB 200824A: Global MASTER-Net observations report
  33. GRB 200815A: MASTER optical observations
  34. Baksan Neutrino Observatory Alert 200819.09: Global MASTER-Net observations report
  35. GRB 200818A: Fermi GBM Final Localization
  36. Fermi trigger No 619487843: Global MASTER-Net observations report
  37. GRB 200809B: Fermi GBM detection
  38. Fermi GRB 200809B: Global MASTER-Net observations report
  39. GRB 200809B: Swift-XRT afterglow detection
  40. GRB 200809B: MAXI/GSC detection
  41. GRB 200808A: Fermi GBM Final Real-time Localization
  42. GRB 200806A: Swift-BAT refined analysis
  43. GRB 200806A: MITSuME Akeno optical upper limits
  44. AX J1846.4-0258: Swift-BAT refined analysis
  45. Fermi GRB 200801A: Global MASTER-Net observations report
  46. GRB 200716C: Kitab optical observations
  47. Konus-Wind observation of GRB 200716C: correction to GCN 28147
  48. Konus-Wind observation of GRB 200716C
  49. GRB 200716C: Insight-HXMT/HE detection
  50. GRB 200716C: CALET Gamma-Ray Burst Monitor detection
  51. GRB 200716C: Swift-BAT refined analysis
  52. GRB 200716C: Fermi GBM detection
  53. GRB 200716C: AGILE/MCAL detection
  54. GRB 200716C: Fermi-LAT detection
  55. GRB 200716C: Swift detection of a burst with an optical counterpart
  56. GRB 200716C: Fermi GBM Final Real-time Localization
  57. Fermi GRB 200714D: Global MASTER-Net observations report
  58. Fermi GRB 200714A: Global MASTER-Net observations report
  59. Fermi-LAT-ANTARES 200407a Coincidence
  60. Fermi GRB 200702A: Global MASTER-Net observations report
  61. Fermi GRB 200626A: Global MASTER-Net observations report
  62. Fermi GRB 200625A: Global MASTER-Net observations report
  63. Fermi GRB 200623A: Global MASTER-Net observations report
  64. Fermi trigger No 614103490: Global MASTER-Net observations report
  65. Baksan Neutrino Observatory Alert 200617.47: Global MASTER-Net observations report
  66. GRB 200615B: CALET Gamma-Ray Burst Monitor detection
  67. LIGO/Virgo MS200614bz: Test Identification of a binary neutron star candidate
  68. GRB 200615B: MAXI/GSC detection
  69. IceCube Alert 200615.62: Global MASTER-Net observations report
  70. Fermi GRB 200615A: Global MASTER-Net observations report
  71. Baksan Neutrino Observatory Alert 200614.34: Global MASTER-Net observations report
  72. Fermi GRB 200613A: Global MASTER-Net observations report
  73. Fermi GRB 200607A: Global MASTER-Net observations report
  74. IPN triangulation of GRB 200605A (short)
  75. 1RXS J1708−4009: Swift-BAT refined analysis
  76. Fermi GRB 200604A: Global MASTER-Net observations report
  77. Fermi GRB 200601A: Global MASTER-Net observations report
  78. GRB 200528A: Swift-BAT refined analysis
  79. Swift GRB 200528A: Global MASTER-Net observations report
  80. GRB 200524A: Correction to the GCN 27800
  81. GRB 200524A: GROWTH-India confirmation of optical afterglow
  82. IceCube Alert 200523.10: Global MASTER-Net observations report
  83. Fermi GRB 200522B: Global MASTER-Net observations report
  84. GRB 200517A: Swift-XRT Confirmation of afterglow
  85. GRB 200519A: BOOTES-3/YA optical counterpart observations
  86. Fermi GBM Sub-Threshold Detection of GRB 200517A
  87. GRB 200519A: Swift detection of a burst with an optical afterglow
  88. GRB 200517A: Swift-XRT afterglow detection
  89. GRB 200514A: AstroSat CZTI detection
  90. Fermi trigger No 611434353: Global MASTER-Net observations report
  91. GRB 200517A: Tiled Swift observations
  92. GRB 200517A: MAXI/GSC detection
  93. Swift J1818.0-1607: BOOTES-3/YA optical upper limit
  94. GRB 200514A: MITSuME Akeno optical upper limits
  95. GRB 200514A: CALET Gamma-Ray Burst Monitor detection
  96. GRB 200514A: MAXI/GSC detection
  97. Baksan Neutrino Observatory Alert 200512.: Global MASTER-Net observations report
  98. SGR 1935+2154: MASTER optical observations
  99. Konus-Wind observation of a very intense bursting activity of SGR 1935+2154
  100. high bursting activity of SGR 1935+2154: CGBM observations

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