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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"

36159 results found.

  1. GRB 210912A: Swift-BAT refined analysis
  2. GRB 210912A: Tautenburg observations
  3. GRB 210912A: CAHA 2.2m Detection
  4. GRB 210912A: Swift-XRT refined Analysis
  5. GRB 210912A: Swift/UVOT Detection
  6. GRB 210912A: Enhanced Swift-XRT position
  7. GRB 210912A: Host-galaxy candidate in PanSTARRS
  8. GRB 210912A: Mondy optical afterglow confirmation
  9. Swift GRB 210912A: Global MASTER-Net observations report
  10. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  11. GRB 210912B: Fermi GBM Final Real-time Localization
  12. GRB 210912A: Swift detection of a burst
  13. GRB 210826A: further Swift-XRT observations
  14. GRB 210909B: GECAM detection
  15. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  16. Fermi GRB 210909A: Global MASTER-Net observations report
  17. GRB 210909A: Fermi GBM Final Real-time Localization
  18. GRB 210905A: Swift/UVOT Upper Limits
  19. GRB 210905A: ATCA detection
  20. GRB 210905A: ALMA detection
  21. GRB 210905A: AstroSat CZTI detection
  22. GRB 210905A, GROND observations
  23. Konus-Wind detection of GRB 210905A
  24. Fermi GBM Sub-Threshold Detection of GRB 210905A
  25. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  26. GRB 210905A: Swift-XRT refined Analysis
  27. GRB 210610A: Maidanak and AbAO optical observations
  28. GRB 210827B: GECAM detection
  29. GRB 210905A: DECam Detection
  30. GRB 210905A: REM NIR afterglow detection
  31. GRB 210905A: VLT/X-shooter spectroscopic redshift
  32. GRB 210905A: Continued LCO Optical Observations
  33. GRB 210905A: LCO Optical Detection
  34. GRB 210905A: Enhanced Swift-XRT position
  35. GRB 210901A: Swift/UVOT Upper Limits
  36. Swift GRB 210905A: Global MASTER-Net observations report
  37. GRB 210905A: Swift detection of a burst
  38. Fermi GRB 210904A: Global MASTER-Net observations report
  39. GRB 210904A: Fermi GBM Final Real-time Localization
  40. Fermi GRB 210903A: Global MASTER-Net observations report
  41. GRB 210903C: Fermi GBM Final Real-time Localization
  42. GRB 210820A: TSHAO optical upper limit
  43. Fermi GRB 210903B: Global MASTER-Net observations report
  44. GRB 210901A: GROND observations
  45. GRB 210903B: Fermi GBM Final Localization
  46. GRB 210903A: Fermi GBM Final Real-time Localization
  47. GRB 210901A: Swift-XRT refined Analysis
  48. GRB 210901A: Swift-BAT refined analysis
  49. GRB 210901A: Enhanced Swift-XRT position
  50. GRB 210901A: LCO Optical Upper Limit
  51. Swift GRB 210901A: Global MASTER-Net observations report
  52. GRB 210901A: Swift detection of a burst
  53. GRB 210827A: further Swift-XRT observations
  54. GRB 210822A: CALET Gamma-Ray Burst Monitor detection
  55. GRB 210827A: Swift/UVOT Upper Limits
  56. GRB 210827A: BOOTES-5/JGT optical upper limit
  57. IBAS Alert n. 9366 not a GRB
  58. GRB 210827A: Fermi GBM Observation
  59. GRB 210826A: AstroSat CZTI detection
  60. Fermi GRB 210827A: Global MASTER-Net observations report
  61. Fermi GRB 210827B: Global MASTER-Net observations report
  62. GRB 210827A: Swift-XRT observations
  63. GRB 210827A: Swift ToO observations
  64. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  65. GRB 210820A: CAHA 2.2m Optical Detection
  66. GRB 210824A: Swift/UVOT Upper Limits
  67. GRB 210826A: Swift/UVOT Upper Limits
  68. GRB 210827B: BALROG localization (Fermi Trigger 651751821 / GRB 210827424)
  69. GRB 210827B: Fermi GBM Final Real-time Localization
  70. GRB 210826A: Swift-XRT observations
  71. GRB 210827A: Fermi GBM Final Real-time Localization
  72. GRB 210822A: CAHA 2.2m observations
  73. GRB 210824A: Swift-BAT refined analysis
  74. GRB 210826A: Fermi-LAT detection
  75. Fermi GRB 210826A: Global MASTER-Net observations report
  76. GRB 210826A: Tiled Swift observations
  77. GRB 210824A: MITSuME Akeno optical upper limits
  78. GRB 210826A: BALROG localization (Fermi Trigger 651654110 / GRB 210826293)
  79. GRB 210826A: Fermi GBM Final Real-time Localization
  80. GRB 210822A: TSHAO continued optical observation
  81. GRB 210822A: VLA detection
  82. GRB 210822A: TSHAO optical observation
  83. GRB 210822A: Swift/UVOT Detection
  84. Swift GRB 210824A: Global MASTER-Net observations report
  85. GRB 210824A: BOOTES-5/JGT optical upper limit
  86. GRB 210824A: Fermi GBM Observation
  87. Fermi GRB 210824A: Global MASTER-Net observations report
  88. GRB 210824A: Nanshan/NEXT optical upper limit
  89. GRB 210824A: Swift-XRT refined Analysis
  90. GRB 210822A: GROND observations
  91. GRB 210824A: Enhanced Swift-XRT position
  92. GRB 210822A: Abbey Ridge Observatory optical afterglow observation
  93. GRB 210824A: Swift detection of a burst
  94. GRB 210824A: Fermi GBM Final Real-time Localization
  95. GRB 210822B: DDOTI Upper Limits on the Afterglow
  96. GRB 210822A: Detection by GRBAlpha
  97. GRB 210822A: GECAM refined analysis
  98. GRB 210820A: GROND observations
  99. Konus-Wind detection of GRB 210822A
  100. GRB 210822A: AstroSat CZTI detection

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