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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"

39470 results found.

  1. GRB 210524A: BALROG localization (Fermi Trigger 643525204 / GRB 210524208)
  2. Fermi GRB 210524A: Global MASTER-Net observations report
  3. GRB 210524A: Fermi GBM Final Real-time Localization
  4. GRB 210522A: GECAM detection
  5. GRB 210520A: Swift-XRT observations
  6. MAXI GRB210521.54: Global MASTER-Net observations report
  7. GRB 210521A: MAXI/GSC detection
  8. GRB210413B: further Swift-XRT observations
  9. GRB 210520A: Fermi GBM detection
  10. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  11. GRB 210520A: Tiled Swift observations
  12. GRB 210520A: Fermi-LAT detection
  13. GRB 210520A: GECAM detection
  14. Fermi GRB 210520A: Global MASTER-Net observations report
  15. GRB 210520A: Fermi GBM Final Real-time Localization
  16. Fermi GBM observation of a bright burst from magneta
  17. GRB 210517A: KCT optical upper limit
  18. Fermi GRB 210519A: Global MASTER-Net observations report
  19. IceCube Alert 210519.86: Global MASTER-Net observations report
  20. IPN triangulation of GRB 210518A
  21. Fermi trigger No 643065622: Global MASTER-Net observations report
  22. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  23. GRB 210519A: Fermi GBM Final Localization
  24. Fermi GRB 210518A: Global MASTER-Net observations report
  25. Konus-Wind detection of GRB 210514A
  26. Fermi trigger No 642991619: Global MASTER-Net observations report
  27. Fermi-LAT Gamma-ray Observations of IceCube-210516A
  28. GRB 210518A: Fermi GBM Final Real-time Localization
  29. IceCube Alert 210515.01: Global MASTER-Net observations report
  30. GRB 210517A: Swift-BAT refined analysis
  31. GRB 210517A: Swift-XRT refined Analysis
  32. GRB 210517A: Swift/UVOT Upper Limits
  33. GRB 210515C: Swift/UVOT Upper Limits
  34. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  35. GRB 210517A: AGILE detection
  36. GRB 210514A: CALET Gamma-Ray Burst Monitor detection
  37. GRB 210517A: Enhanced Swift-XRT position
  38. Swift GRB 210517A: Global MASTER-Net observations report
  39. GRB 210517A: Swift detection of a burst
  40. Fermi GRB 210516A: Global MASTER-Net observations report
  41. GRB 210516A: Fermi GBM Final Real-time Localization
  42. IceCube Alert 210516.61: Global MASTER-Net observations report
  43. GRB 210515C: LCO Optical Upper Limit
  44. GRB 210504A: LCO Optical Afterglow Detection
  45. GRB 210514A: Swift/UVOT Upper Limits
  46. AMON IC_HAWC NuEm-210515A / NuEm-210515B : No neutrino counterpart detected with ANTARES
  47. GRB 210515C: Swift-XRT refined Analysis
  48. Swift GRB210515.83: Global MASTER-Net observations report
  49. GRB 210515C: Swift-BAT refined analysis
  50. GRB 210515C: Swift detection of a burst
  51. Fermi GRB 210515B: Global MASTER-Net observations report
  52. GRB 210514A: Swift-BAT refined analysis
  53. Fermi GRB 210515A: Global MASTER-Net observations report
  54. GRB 210515B: Fermi GBM Final Real-time Localization
  55. GRB 210515A: Fermi GBM Final Real-time Localization
  56. Swift GRB210514.71: Global MASTER-Net observations report
  57. GRB 210514A: Swift XRT light curve is fading
  58. GRB 210514A: Swift-XRT refined Analysis
  59. GRB 210514A: Enhanced Swift-XRT position
  60. GRB 210514A: update on the BAT trigger time and burst duration
  61. GRB 210514A: Swift detection of a burst
  62. Konus-Wind detection of GRB 210511B
  63. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  64. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  65. Fermi trigger No 642538568: Global MASTER-Net observations report
  66. IPN triangulation of GRB 210511B
  67. Short GRB 210323A: likely host galaxy detection
  68. GRB 210511B: DDOTI Upper Limits on the Afterglow
  69. IPN triangulation of GRB 210427A
  70. GRB 210511B: Fermi GBM observation
  71. Fermi-LAT Gamma-ray Observations of IceCube-210510A
  72. Fermi GRB 210511A: Global MASTER-Net observations report
  73. Fermi GRB 210510A: DDOTI Upper Limits on the Afterglow
  74. Fermi GRB 210511B: Global MASTER-Net observations report
  75. GRB 210511B: AGILE detection
  76. GRB 210511B: GECAM detection
  77. GRB 210511B: BALROG localization (Fermi Trigger 642425204 / GRB 210511477)
  78. GRB 210511B: Fermi GBM Final Real-time Localization
  79. GRB 210511A: Fermi GBM Final Real-time Localization
  80. Fermi GRB 210510A: Global MASTER-Net observations report
  81. GRB 201228B: Swift/BAT-GUANO archival detection and arcminute localization
  82. GRB 200716A: Swift/BAT-GUANO archival detection and arcminute localization
  83. IceCube Alert 210510.20: Global MASTER-Net observations report
  84. GRB 210510A: Fermi GBM Final Real-time Localization
  85. GRB 210509A: RATIR Optical and NIR Upper Limits
  86. GRB 210509A: Swift/UVOT Upper Limits
  87. GRB 210509A: Swift-XRT refined Analysis
  88. GRB 210509A: Swift-BAT refined analysis
  89. Swift GRB 210509A: Global MASTER-Net observations report
  90. GRB 210509A: Enhanced Swift-XRT position
  91. GRB 210509A: BOOTES-4/MET optical upper limit
  92. GRB 210509A: Swift-XRT observations
  93. GRB 210509A: Swift detection of a burst
  94. GRB 210506A: Swift/BAT-GUANO position retraction
  95. IPN triangulation of GRB 210506A
  96. Fermi GRB 210507A: Global MASTER-Net observations report
  97. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  98. ZTF21aayokph (AT2021lfa): continued Mondy optical observations
  99. GRB 210507A: Fermi GBM Final Real-time Localization
  100. Integral GRB210507.04: Global MASTER-Net observations report

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