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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"

39471 results found.

  1. GRB 210524B: Fermi GBM Final Real-time Localization
  2. GRB 210524A: BALROG localization (Fermi Trigger 643525204 / GRB 210524208)
  3. Fermi GRB 210524A: Global MASTER-Net observations report
  4. GRB 210524A: Fermi GBM Final Real-time Localization
  5. GRB 210522A: GECAM detection
  6. GRB 210520A: Swift-XRT observations
  7. MAXI GRB210521.54: Global MASTER-Net observations report
  8. GRB 210521A: MAXI/GSC detection
  9. GRB210413B: further Swift-XRT observations
  10. GRB 210520A: Fermi GBM detection
  11. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  12. GRB 210520A: Tiled Swift observations
  13. GRB 210520A: Fermi-LAT detection
  14. GRB 210520A: GECAM detection
  15. Fermi GRB 210520A: Global MASTER-Net observations report
  16. GRB 210520A: Fermi GBM Final Real-time Localization
  17. Fermi GBM observation of a bright burst from magneta
  18. GRB 210517A: KCT optical upper limit
  19. Fermi GRB 210519A: Global MASTER-Net observations report
  20. IceCube Alert 210519.86: Global MASTER-Net observations report
  21. IPN triangulation of GRB 210518A
  22. Fermi trigger No 643065622: Global MASTER-Net observations report
  23. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  24. GRB 210519A: Fermi GBM Final Localization
  25. Fermi GRB 210518A: Global MASTER-Net observations report
  26. Konus-Wind detection of GRB 210514A
  27. Fermi trigger No 642991619: Global MASTER-Net observations report
  28. Fermi-LAT Gamma-ray Observations of IceCube-210516A
  29. GRB 210518A: Fermi GBM Final Real-time Localization
  30. IceCube Alert 210515.01: Global MASTER-Net observations report
  31. GRB 210517A: Swift-BAT refined analysis
  32. GRB 210517A: Swift-XRT refined Analysis
  33. GRB 210517A: Swift/UVOT Upper Limits
  34. GRB 210515C: Swift/UVOT Upper Limits
  35. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  36. GRB 210517A: AGILE detection
  37. GRB 210514A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 210517A: Enhanced Swift-XRT position
  39. Swift GRB 210517A: Global MASTER-Net observations report
  40. GRB 210517A: Swift detection of a burst
  41. Fermi GRB 210516A: Global MASTER-Net observations report
  42. GRB 210516A: Fermi GBM Final Real-time Localization
  43. IceCube Alert 210516.61: Global MASTER-Net observations report
  44. GRB 210515C: LCO Optical Upper Limit
  45. GRB 210504A: LCO Optical Afterglow Detection
  46. GRB 210514A: Swift/UVOT Upper Limits
  47. AMON IC_HAWC NuEm-210515A / NuEm-210515B : No neutrino counterpart detected with ANTARES
  48. GRB 210515C: Swift-XRT refined Analysis
  49. Swift GRB210515.83: Global MASTER-Net observations report
  50. GRB 210515C: Swift-BAT refined analysis
  51. GRB 210515C: Swift detection of a burst
  52. Fermi GRB 210515B: Global MASTER-Net observations report
  53. GRB 210514A: Swift-BAT refined analysis
  54. Fermi GRB 210515A: Global MASTER-Net observations report
  55. GRB 210515B: Fermi GBM Final Real-time Localization
  56. GRB 210515A: Fermi GBM Final Real-time Localization
  57. Swift GRB210514.71: Global MASTER-Net observations report
  58. GRB 210514A: Swift XRT light curve is fading
  59. GRB 210514A: Swift-XRT refined Analysis
  60. GRB 210514A: Enhanced Swift-XRT position
  61. GRB 210514A: update on the BAT trigger time and burst duration
  62. GRB 210514A: Swift detection of a burst
  63. Konus-Wind detection of GRB 210511B
  64. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  65. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  66. Fermi trigger No 642538568: Global MASTER-Net observations report
  67. IPN triangulation of GRB 210511B
  68. Short GRB 210323A: likely host galaxy detection
  69. GRB 210511B: DDOTI Upper Limits on the Afterglow
  70. IPN triangulation of GRB 210427A
  71. GRB 210511B: Fermi GBM observation
  72. Fermi-LAT Gamma-ray Observations of IceCube-210510A
  73. Fermi GRB 210511A: Global MASTER-Net observations report
  74. Fermi GRB 210510A: DDOTI Upper Limits on the Afterglow
  75. Fermi GRB 210511B: Global MASTER-Net observations report
  76. GRB 210511B: AGILE detection
  77. GRB 210511B: GECAM detection
  78. GRB 210511B: BALROG localization (Fermi Trigger 642425204 / GRB 210511477)
  79. GRB 210511B: Fermi GBM Final Real-time Localization
  80. GRB 210511A: Fermi GBM Final Real-time Localization
  81. Fermi GRB 210510A: Global MASTER-Net observations report
  82. GRB 201228B: Swift/BAT-GUANO archival detection and arcminute localization
  83. GRB 200716A: Swift/BAT-GUANO archival detection and arcminute localization
  84. IceCube Alert 210510.20: Global MASTER-Net observations report
  85. GRB 210510A: Fermi GBM Final Real-time Localization
  86. GRB 210509A: RATIR Optical and NIR Upper Limits
  87. GRB 210509A: Swift/UVOT Upper Limits
  88. GRB 210509A: Swift-XRT refined Analysis
  89. GRB 210509A: Swift-BAT refined analysis
  90. Swift GRB 210509A: Global MASTER-Net observations report
  91. GRB 210509A: Enhanced Swift-XRT position
  92. GRB 210509A: BOOTES-4/MET optical upper limit
  93. GRB 210509A: Swift-XRT observations
  94. GRB 210509A: Swift detection of a burst
  95. GRB 210506A: Swift/BAT-GUANO position retraction
  96. IPN triangulation of GRB 210506A
  97. Fermi GRB 210507A: Global MASTER-Net observations report
  98. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  99. ZTF21aayokph (AT2021lfa): continued Mondy optical observations
  100. GRB 210507A: Fermi GBM Final Real-time Localization

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