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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19666 results found.

  1. Swift GRB 211025A: Global MASTER-Net observations report
  2. GRB 211023B: LDT Optical Afterglow Detection
  3. GRB 211025A: Swift-BAT refined analysis
  4. GRB 211025A: Swift-XRT refined Analysis
  5. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  6. GRB 211024B: Swift-XRT refined Analysis
  7. Possible Short GRB 211023B: CAHA 2.2m Detection
  8. GRB 211025A: Swift/UVOT Detection
  9. GRB 211024B: Swift-BAT refined analysis
  10. GRB 211025A: Enhanced Swift-XRT position
  11. GRB 211025A: Swift detection of a burst
  12. GECAM detection of a short burst probably from SGR J1555.2-5402
  13. GRB 211024B: Nanshan/NEXT optical afterglow detection
  14. Swift GRB 211024B: Global MASTER-Net observations report
  15. GRB 211024B: Swift detection of a burst
  16. GRB 211023B: Swift-BAT refined analysis
  17. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  18. GRB 211023B: Swift/UVOT Detection
  19. GRB 211023B: TSHAO optical observation
  20. GRB 211023B: Swift-XRT refined Analysis
  21. GRB 211023B: Enhanced Swift-XRT position
  22. Swift GRB 211023B: Global MASTER-Net observations report
  23. GRB 211023A: Fermi-LAT detection
  24. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  25. IPN Triangulation of GRB 210927B
  26. GRB 211018A: Swift ToO observations
  27. BepiColombo MGNS joins the IPN
  28. GRB 211018A: Fermi-LAT detection
  29. Swift GRB211017.99: Global MASTER-Net observations report
  30. Swift trigger 1078701: MITSuME Akeno optical upper limits
  31. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  32. Swift GRB211010.45: Global MASTER-Net observations report
  33. Swift Trigger 1078701 is probably not a GRB
  34. GECAM observation of a burst from SGR J1555.2-5402
  35. Correction to GCN 30915: GRB 210928A: Swift-XRT analysis
  36. GRB 210928A: Kinder SLT-40cm optical limits
  37. GRB 210930A: Swift-BAT refined analysis
  38. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  39. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  40. GRB 210928A: Swift-XRT refined Analysis
  41. GRB 210928A: Fermi-LAT detection
  42. Swift GRB211001.03 / trigger 1076121 : MASTER OT retraction
  43. GRB 210930A: CAHA 2.2m telescope optical limit
  44. Swift GRB211001.03: Global MASTER-Net observations report
  45. Swift Trigger 1076121 is not a GRB
  46. Swift GRB211001.03: Global MASTER-Net OT detection
  47. GRB 210930A: Swift/UVOT Upper Limits
  48. GRB 210930A: Swift-XRT refined Analysis
  49. Swift GRB 210930A: Global MASTER-Net observations report
  50. GRB 210930A: Enhanced Swift-XRT position
  51. GRB 210930A: Swift detection of a burst
  52. IPN triangulation of GRB 210925B
  53. GRB 210919A: iTelescope T-11 upper limits
  54. GRB 210919A OSN 1.5m Source Confirmation
  55. GRB 210919A CAHA 2.2m Observations: Afterglow/Host Galaxy Candidate
  56. IceCube-210922A: No Candidate Counterparts from Swift/XRT follow up observations
  57. GRB 210919A: Swift-BAT refined analysis
  58. GRB 210919A: Lowell Discovery Telescope upper limits (correction to GCN 30859)
  59. GRB 210919A: Swift/UVOT Upper Limits
  60. GRB 210919A: MITSuME Akeno optical upper limits
  61. GRB 210919A: Swift-XRT refined Analysis
  62. GRB 210919A: AbAO optical upper limit
  63. GRB 210919A: Enhanced Swift-XRT position
  64. GRB 210919A: LCO Optical Upper Limit
  65. GRB 210919A: BOOTES-2/TELMA optical upper limit
  66. Swift GRB 210919A: Global MASTER-Net observations report
  67. GRB 210919A: Swift detection of a short burst
  68. Swift trigger 1073821: detection of IGR J16418-4532
  69. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  70. GRB 210912A: Swift-BAT refined analysis
  71. GRB 210912A: CAHA 2.2m Detection
  72. GRB 210912A: Swift-XRT refined Analysis
  73. GRB 210912A: Swift/UVOT Detection
  74. GRB 210912A: Enhanced Swift-XRT position
  75. GRB 210912A: Host-galaxy candidate in PanSTARRS
  76. Swift GRB 210912A: Global MASTER-Net observations report
  77. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  78. GRB 210912A: Swift detection of a burst
  79. Swift GRB210910.42: Global MASTER-Net observations report
  80. IPN triangulation of a bright burst from SGR 1935+2154
  81. GRB 210826A: further Swift-XRT observations
  82. Swift detection of a burst from SGR Swift J1555.2-5402
  83. GECAM observation of a burst from SGR J1555.2-5402
  84. GRB 210905A: Swift/UVOT Upper Limits
  85. GRB 210905A: AstroSat CZTI detection
  86. GRB 210905A, GROND observations
  87. Konus-Wind detection of GRB 210905A
  88. Fermi GBM Sub-Threshold Detection of GRB 210905A
  89. GRB 210905A: Swift-XRT refined Analysis
  90. GRB 210905A: DECam Detection
  91. GRB 210905A: Continued LCO Optical Observations
  92. GRB 210905A: LCO Optical Detection
  93. GRB 210905A: Enhanced Swift-XRT position
  94. GRB 210901A: Swift/UVOT Upper Limits
  95. Swift GRB 210905A: Global MASTER-Net observations report
  96. GRB 210905A: Swift detection of a burst
  97. Swift GRB210903.59: Global MASTER-Net observations report
  98. Swift GRB210903.58: Global MASTER-Net observations report
  99. Swift GRB210903.58: Global MASTER-Net observations report
  100. GRB 210901A: GROND observations

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