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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

27301 results found.

  1. GRB 190701A: COATLI Optical Observations
  2. GRB 190630C: Swift/UVOT Upper Limits
  3. GRB 190630B: Swift/UVOT Upper Limits
  4. GRB 190630C: Swift-BAT refined analysis
  5. LIGO/Virgo S190630ag: No counterpart candidates in the Swift/BAT Observations
  6. GRB 190701A: Swift detection of a burst
  7. LIGO/Virgo S190630ag: No counterpart candidates in Fermi-LAT observations
  8. Swift GRB190631. Global MASTER-Net observations report
  9. LIGO/Virgo S190630ag: Upper limits from Fermi-GBM Observations
  10. GRB 190630C: Swift detection of a burst
  11. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S190630ag: No counterpart candidates in HAWC observations
  13. LIGO/Virgo S190630ag Global MASTER-Net observations report
  14. GRB 190630B: Swift-XRT refined Analysis
  15. GRB 190630B, Swift-BAT refined analysis
  16. IceCube-190629A: Upper limits from Fermi-GBM Observations
  17. Fermi trigger No 583567803 Global MASTER-Net observations report
  18. GRB Swift Trigger 912102: KAIT Optical Afterglow Candidate
  19. Swift Trigger 912102: possible GRB 190630B
  20. GRB 190630A: Fermi GBM Final Real-time Localization
  21. Baksan Neutrino Observatory Alert 190629.56 Global MASTER-Net observations report
  22. IceCube Alert 190629.81 Global MASTER-Net observations report
  23. GRB 190627A: Swift-XRT refined Analysis
  24. GRB 190627A: GMG observation at the second epoch
  25. GRB 190627A: NOT optical observations
  26. GRB 190627A: Optical imaging by D50 from Ondrejov
  27. GRB 190627A: Optical imaging and spectroscopy from Calar Alto
  28. GRB 190627A: Swift-BAT refined analysis (short-soft burst)
  29. GRB 190628A: Fermi GBM Final Real-time Localization
  30. GRB 190627A: GMG observation
  31. GRB 190627A: MASTER optical counterpart observation
  32. GRB 190627A: Montarrenti Observatory optical detection
  33. Fermi trigger No 583327924 Global MASTER-Net observations report
  34. GRB 190627A: Swift/UVOT Detection
  35. GRB 190627A: Swift detection of a burst
  36. Fermi trigger No 583245413 Global MASTER-Net observations report
  37. Fermi trigger No 583245413 Global MASTER-Net observations report
  38. Fermi trigger No 583221986 Global MASTER-Net observations report
  39. GRB 190626B: Fermi GBM Final Real-time Localization
  40. GRB 190626A: Fermi GBM Final Real-time Localization
  41. Fermi trigger No 583111521 Global MASTER-Net observations report
  42. Swift Trigger 911102 is likely not an astrophysical event
  43. IceCube-190619A: prompt emission upper limits from AstroSat-CZTI
  44. Swift GRB190624.86 Global MASTER-Net observations report
  45. Swift trigger 911102: D50 optical limit
  46. Swift Trigger 911102: a possible GRB
  47. GRB 190623A: Fermi GBM Final Real-time Localization
  48. Fermi trigger No 582886211 Global MASTER-Net observations report
  49. GRB 190622A: BALROG localization (Fermi Trigger 582886211 / GRB 190622368)
  50. GRB 190622A: Fermi GBM Final Real-time Localization
  51. Fermi trigger No 582856902 Global MASTER-Net observations report
  52. Fermi trigger No 582748289 Global MASTER-Net observations report
  53. Fermi trigger No 582759998 Global MASTER-Net observations report
  54. GRB 190620A: BALROG localization (Fermi Trigger 582725415 / GRB 190620507)
  55. GRB 190620A: Fermi GBM Final Real-time Localization
  56. Fermi trigger No 582615488 Global MASTER-Net observations report
  57. Fermi trigger No 582615488 Global MASTER-Net observations report
  58. IceCube-190619A: not observable by Fermi-GBM
  59. Fermi GBM trigger 190619235/582615488 likely not a GRB
  60. Fermi trigger No 582646590 Global MASTER-Net observations report
  61. GRB 190619B: BALROG localization (Fermi Trigger 582646590 / GRB 190619595)
  62. GRB 190619B: Fermi GBM Final Real-time Localization
  63. GRB 190613A: SEDM Observations
  64. Fermi trigger No 582596766 Global MASTER-Net observations report
  65. GRB 190613B: JCMT SCUBA-2 sub-mm observations
  66. GRB 190619A: Fermi GBM Final Real-time Localization
  67. GRB 190615B: Insight-HXMT/HE detection
  68. GRB 190615A: Insight-HXMT/HE detection
  69. Fermi trigger No 582304592 Global MASTER-Net observations report
  70. GRB 190615A: Fermi GBM Final Real-time Localization
  71. Fermi trigger No 582159815 Global MASTER-Net observations report
  72. GRB 190613B: SEDM Observations
  73. GRB 190613A: SEDM Observations
  74. GRB 190610A: Swift/UVOT Upper Limits
  75. GRB 190613B: GROND Detection of the Optical/NIR Afterglow
  76. GRB 190611B: CALET Gamma-Ray Burst Monitor detection
  77. GRB 190613B: Insight-HXMT/HE detection
  78. GRB 190613B: BOOTES-5/JGT early optical observations
  79. Fermi trigger No 582115625 Global MASTER-Net observations report
  80. GRB 190613B: Swift-XRT refined Analysis
  81. GRB 190613A: FRAM-ORM afterglow detection
  82. GRB 190613B: Swift-BAT refined analysis
  83. GRB 190613A, Swift-BAT refined analysis
  84. GRB 190613B: Swift/UVOT Detection
  85. GRB 190613A: Fermi GBM detection
  86. GRB 190613A: Swift/UVOT Detection
  87. GRB 190613B: Fermi GBM observation
  88. GRB 190611B: BALROG localization (Fermi Trigger 581986074 / GRB 190611950)
  89. GRB 190613A: Swift-XRT refined Analysis
  90. GRB 190613B: BALROG localization (Fermi Trigger 582115625 / GRB 190613449)
  91. GRB 190613B: Swift detection of a burst with an optical counterpart
  92. GRB 190613B: Fermi GBM Final Real-time Localization
  93. GRB 190610A: CALET Gamma-Ray Burst Monitor detection
  94. GRB 190613A: MASTER OT detection
  95. Swift GRB190613.17 Global MASTER-Net observations report
  96. GRB 190613A: BALROG localization (Fermi Trigger 582091643 / GRB 190613172)
  97. GRB 190613A: Fermi GBM Final Real-time Localization
  98. GRB 190613A: Swift detection of a burst with an optical counterpart
  99. Fermi trigger No 582091643 Global MASTER-Net observations report
  100. Fermi trigger No 582012834 Global MASTER-Net observations report

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