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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3114 results found.

  1. GRB 210917A: Fermi GBM Final Real-time Localization
  2. AGILE observations of two bright bursts from SGR 1935+2154
  3. Fermi trigger No 653083551: Global MASTER-Net observations report
  4. Fermi trigger No 653066130: Global MASTER-Net observations report
  5. Fermi trigger No 653049776: Global MASTER-Net observations report
  6. Fermi trigger No 653010039: Global MASTER-Net observations report
  7. IPN triangulation of a bright burst from SGR 1935+2154
  8. Fermi trigger No 652927551: Global MASTER-Net observations report
  9. Fermi trigger No 652911693: Global MASTER-Net observations report
  10. Fermi trigger No 652906639: Global MASTER-Net observations report
  11. Fermi GRB 210909A: Global MASTER-Net observations report
  12. Fermi trigger No 652585475: Global MASTER-Net observations report
  13. GRB 210905A: Swift detection of a burst
  14. GRB 210904A: Fermi GBM Final Real-time Localization
  15. Fermi GRB 210903A: Global MASTER-Net observations report
  16. Fermi GRB 210827A: Global MASTER-Net observations report
  17. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  18. GRB 210826A: Swift-XRT observations
  19. GRB 210822A: TSHAO continued optical observation
  20. GRB 210822A: TSHAO optical observation
  21. Swift GRB 210824A: Global MASTER-Net observations report
  22. Fermi trigger No 651306769: Global MASTER-Net observations report
  23. Fermi GRB 210822B: Global MASTER-Net observations report
  24. Konus-Wind detection of GRB 210818A
  25. GRB 210812A is consistent with being a lensed GRB
  26. IceCube-210811A: No Candidate Counterparts from the Zwicky Transient Facility
  27. Fermi GRB 210813A: Global MASTER-Net observations report
  28. GRB 210812A: BALROG localization (Fermi Trigger 650479626 / GRB 210812699)
  29. GRB 210812A: Fermi GBM Final Real-time Localization
  30. Fermi GRB 210807C: Global MASTER-Net observations report
  31. Fermi GRB 210807B: Global MASTER-Net observations report
  32. Swift GRB210731.62: Global MASTER-Net observations report
  33. GRB 210731A: MeerLICHT optical afterglow detection
  34. Trigger 1062273: Swift detection of 4U 1700-377
  35. IPN triangulation of GRB 210727A (short)
  36. Fermi trigger No 648959581: Global MASTER-Net observations report
  37. GRB 210725A: Fermi GBM detection
  38. GRB 210725A: CALET Gamma-Ray Burst Monitor detection
  39. Fermi trigger No 648868114: Global MASTER-Net observations report
  40. GRB 210725A: Swift detection of a burst
  41. GRB 210723A: Swift detection of a burst
  42. Fermi trigger No 648602917: Global MASTER-Net observations report
  43. Fermi trigger No 648278666: Global MASTER-Net observations report
  44. Fermi trigger No 647942198: Global MASTER-Net observations report
  45. Fermi trigger No 647805873: Global MASTER-Net observations report
  46. Fermi trigger No 647624281: Global MASTER-Net observations report
  47. MAXI GRB210709.93: Global MASTER-Net observations report
  48. Fermi trigger No 647522278: Global MASTER-Net observations report
  49. GRB 210704B: AstroSat CZTI detection
  50. Fermi trigger No 647120009: Global MASTER-Net observations report
  51. GRB 210702A: AGILE detection
  52. IceCube-210629A: One Candidate Counterpart from the Zwicky Transient Facility
  53. Fermi GRB 210627B: Global MASTER-Net observations report
  54. Fermi GRB 210627A: Global MASTER-Net observations report
  55. Fermi GRB 210625A: Global MASTER-Net observations report
  56. Fermi trigger No 646189108: Global MASTER-Net observations report
  57. Fermi trigger No 646194855: Global MASTER-Net observations report
  58. Fermi GRB 210622B: Global MASTER-Net observations report
  59. Swift GRB210618.07: Global MASTER-Net observations report
  60. Fermi trigger No 645485036: Global MASTER-Net observations report
  61. Fermi GRB 210615A: Global MASTER-Net observations report
  62. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  63. Follow-up on HAWC Transient Monitoring Alert J0020+3108
  64. GRB 210610B: Further SAO RAS optical observations
  65. Swift-BAT Trigger 1055000: Swift detection of an outburst from 4U 1543-47
  66. GRB 210610B: iTelescope optical afterglow observations
  67. Fermi trigger No 645047470: Global MASTER-Net observations report
  68. GRB210610A: MeerLICHT multi-colour photometry
  69. GRB 210610A: MITSuME Akeno optical observation
  70. IPN triangulation of GRB 210605A (short)
  71. Fermi trigger No 644449593: Global MASTER-Net observations report
  72. Swift Detection of probable new Swift SGR J1555.2-5402
  73. Fermi trigger No 644359567: Global MASTER-Net observations report
  74. GRB 210602A: MAXI/GSC detection
  75. Fermi GRB 210601A: Global MASTER-Net observations report
  76. GRB210529B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 644025222)
  77. Fermi GRB 210529B: Global MASTER-Net observations report
  78. GRB 210524B: Fermi GBM Final Real-time Localization
  79. Fermi trigger No 643065622: Global MASTER-Net observations report
  80. Fermi trigger No 642991619: Global MASTER-Net observations report
  81. Fermi GRB 210516A: Global MASTER-Net observations report
  82. Fermi GRB 210515B: Global MASTER-Net observations report
  83. Fermi GRB 210515A: Global MASTER-Net observations report
  84. GRB 210514A: update on the BAT trigger time and burst duration
  85. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  86. IceCube-210510A: No candidate counterparts from the Zwicky Transient Facility
  87. Fermi GRB 210511A: Global MASTER-Net observations report
  88. Fermi GRB 210510A: Global MASTER-Net observations report
  89. Swift trigger 1047857 is 4U 1700-377
  90. Fermi GRB 210507A: Global MASTER-Net observations report
  91. Fermi GRB 210501A: Global MASTER-Net observations report
  92. Fermi trigger No 641601187: Global MASTER-Net observations report
  93. Fermi GRB 210430B: Global MASTER-Net observations report
  94. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  95. GRB 210422A: Swift detection of a burst
  96. GRB 210420B: Tautenburg observations
  97. Fermi GRB 210420A: Global MASTER-Net observations report
  98. Swift GRB 210421A: Global MASTER-Net observations report
  99. GRB 210413B: LOAO optical upper limit
  100. GRB 210411B: AstroSat CZTI detection

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