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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"

39490 results found.

  1. Konus-Wind detection of GRB 210406A
  2. GRB 210406A: Fermi GBM detection
  3. GRB 210406A: Mondy optical upper limit
  4. GRB 210406A: Konkoly Obs. optical upper limit
  5. GRB 210406A: BOOTES-4/MET optical upper limit
  6. GRB 210406A: A long GRB detected by INTEGRAL
  7. Integral GRB210406.72: Global MASTER-Net observations report
  8. GRB 210402A: MASTER prompt and follow up optical observation
  9. GRB 210402A: Swift/UVOT Upper Limits
  10. GRB 210402A: Fermi GBM detection
  11. GRB 210402A: Further NOT optical observations
  12. GRB 210402A: Swift-BAT refined analysis
  13. GRB 210404.141: DDOTI Upper Limits
  14. GRB 210207B: Prompt and very late time observations with HCT.
  15. GRB 210401A: GECAM detection
  16. GRB 210402A: NOT optical afterglow candidate
  17. Fermi trigger No 639199407: Global MASTER-Net observations report
  18. GRB 210402A: BOOTES-network early optical upper limit
  19. GRB 210403A: Swift-BAT refined analysis
  20. GRB 210402A: LBT observations
  21. GRB 210402A: DDOTI Upper Limits
  22. Swift GRB210403.35: Global MASTER-Net observations report
  23. GRB 210402A: Swift-XRT refined Analysis
  24. GRB 210330A: AstroSat CZTI detection
  25. GRB 210403A: Swift detection of a burst
  26. GRB 210402A: Montarrenti Observatory upper limit
  27. GRB 210328A: AstroSat CZTI detection
  28. GRB 210402A: NOT optical upper limits
  29. Konus-Wind detection of GRB 210401A
  30. GRB 210402A: Swift detection of a burst
  31. Fermi trigger No 639093861: Global MASTER-Net observations report
  32. Swift GRB210402.92: Global MASTER-Net observations report
  33. Fermi GRB 210401A: Global MASTER-Net observations report
  34. GRB 210401A: Fermi GBM Final Real-time Localization
  35. GRB 210330A: MASTER optical observation
  36. GRB 210328A: GECAM detection
  37. GRB 210330A: GECAM detection
  38. GRB 210324A: AstroSat CZTI detection
  39. GRB 210324C: AstroSat CZTI detection
  40. GRB 210328A: BALROG localization (Fermi Trigger / GRB 210328865)
  41. GRB 210328A: Fermi GBM Final Real-time Localization
  42. GRB 210326A: Insight-HXMT/HE detection
  43. GRB 210326A: Fermi GBM Final Localization
  44. Fermi trigger No 638414549: Global MASTER-Net observations report
  45. Konus-Wind detection of GRB 210324C
  46. IPN triangulation of GRB 210324C
  47. GRB 210323A: Insight-HXMT/HE detection
  48. GRB 210321A: OSN Upper Limit
  49. GRB 210323A: MASTER optical observation
  50. Fermi GRB 210324C: Global MASTER-Net observations report
  51. Fermi GRB 210324B: Global MASTER-Net observations report
  52. GRB 210323A: Swift-BAT refined analysis
  53. GRB 210323A: Gemini-North Optical Source Detection
  54. GRB 210324C: BALROG localization (Fermi Trigger 638308803 / GRB 210324833)
  55. GRB 210324C: Fermi GBM Final Real-time Localization
  56. Short GRB 210323A: GTC Observations
  57. GRB 210312B: OSN Afterglow Observations
  58. GRB 210324B: Fermi GBM Final Real-time Localization
  59. GRB 210323B: Swift ToO observations
  60. Konus-Wind detection of GRB 210323A (short)
  61. GRB 210323A: Swift/UVOT Upper Limits
  62. GRB 210323A: Classification and redshift estimation
  63. GRB 210323A: Kitab optical upper limit
  64. GRB 210323A: Fermi GBM detection
  65. GRB 210323A: Mondy optical observations, counterpart detection
  66. GRB 210324A: Fermi GBM Final Real-time Localization
  67. GRB 210318A: Swift/UVOT Upper Limits
  68. GRB 210323A: Swift-XRT refined Analysis
  69. GRB 210323A: Enhanced Swift-XRT position
  70. GRB 210323A: NOT optical afterglow candidate
  71. Swift GRB 210323A: Global MASTER-Net observations report
  72. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  73. GRB 210323A: Nanshan/NEXT optical upper limit
  74. GRB 210323A: Swift detection of a short burst
  75. Fermi GBM trigger 637977270/210320996 is not a GRB
  76. GRB 210321A: Swift/UVOT Detection
  77. Konus-Wind detection of GRB 210321A
  78. GRB 210318B: Swift/UVOT Upper Limits
  79. GRB 210321A: DDOTI Position Correction
  80. IceCube Alert 210322.11: Global MASTER-Net observations report
  81. GRB 210321A: CrAO optical upper limit
  82. GRB 210321A: Swift-BAT refined analysis
  83. IceCube 135113_19489408.amon: Swift-XRT observations
  84. GRB 210321A: Mondy optical observations
  85. GRB 210321A: Xinglong GWAC-F60A optical observation
  86. GRB 210321A: Swift-XRT refined Analysis
  87. GRB 210321A: Redshift from OSIRIS/GTC
  88. GRB 210321A: NOT optical afterglow detection and redshift limit
  89. GRB 210321A: MASTER optical observation
  90. MAXI GRB210320.89: Global MASTER-Net observations report
  91. GRB 210321A: Enhanced Swift-XRT position
  92. GRB 210321A: DDOTI Afterglow Confirmation
  93. GRB 210321A: Swift/UVOT Detection
  94. GRB 210321A: Swift-XRT observations
  95. GRB 210321A: Swift detection of a burst
  96. GRB 210320A: MAXI/GSC detection
  97. GRB 210318B: MITSuME Okayama optical upper limits
  98. GRB 201216C: VIRT optical observations
  99. GRB 200524A: Redshift from Gemini-North
  100. GRB 210318A: Swift-BAT refined analysis

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