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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"

36142 results found.

  1. Fermi GRB 211024A: Global MASTER-Net observations report
  2. GRB 211024A: Fermi GBM Final Real-time Localization
  3. GRB 211023A: Fermi-LAT detection
  4. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  5. GRB 211023A: Fermi GBM Final Real-time Localization
  6. IPN Triangulation of GRB 210927B
  7. GRB 211022A: GECAM detection
  8. GRB 211018A: Swift ToO observations
  9. GRB 211021A: BALROG localization (Fermi Trigger 656506979 / GRB 211021460)
  10. BepiColombo MGNS joins the IPN
  11. GRB 211018A: Fermi GBM observation
  12. GRB 211019A: Detection by GRBAlpha
  13. GRB 211018A: Detection by GRBAlpha
  14. Fermi GRB 211019A: Global MASTER-Net observations report
  15. GRB 211018A: Fermi-LAT detection
  16. GRB 211019A: BALROG localization (Fermi Trigger 656315976 / GRB 211019250)
  17. GRB 211019A: Fermi GBM Final Real-time Localization
  18. GRB 210919A: LDT optical observations and candidate host galaxies
  19. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  20. Swift Trigger 1078701 is probably not a GRB
  21. Fermi Gamma-ray Burst Monitor trigger 211008665/655401471 is not a GRB
  22. GRB 211008A: BALROG localization (Fermi Trigger 655401471 / GRB 211008665)
  23. GRB 210928A: MeerKAT detection
  24. Konus-Wind detection of GRB 210928A
  25. Correction to GCN 30915: GRB 210928A: Swift-XRT analysis
  26. GRB 210928A: Kinder SLT-40cm optical limits
  27. GRB 210930A: Swift-BAT refined analysis
  28. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  29. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  30. GRB 210928A: Swift-XRT refined Analysis
  31. GRB 210928A: Fermi GBM observation
  32. GRB 210928A: Fermi-LAT detection
  33. GRB 210927B: GECAM detection
  34. GRB 210930A: CAHA 2.2m telescope optical limit
  35. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  36. Swift Trigger 1076121 is not a GRB
  37. GRB 210930A: Swift/UVOT Upper Limits
  38. GRB 210930A: Swift-XRT refined Analysis
  39. Swift GRB 210930A: Global MASTER-Net observations report
  40. GRB 210930A: Enhanced Swift-XRT position
  41. Fermi GRB 210929B: Global MASTER-Net observations report
  42. GRB 210930A: Swift detection of a burst
  43. GRB 210929B: Fermi GBM Final Real-time Localization
  44. GRB 210929A: Fermi GBM Final Real-time Localization
  45. GRB 210927A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 654396242)
  46. GRB 210925B: AstroSat CZTI detection
  47. IPN triangulation of GRB 210925B
  48. GRB 210926A: AstroSat CZTI detection
  49. GRB 210919A: iTelescope T-11 upper limits
  50. GRB 210926A: GECAM detection
  51. GRB 210927A: Fermi GBM Final Real-time Localization
  52. GRB 210919A OSN 1.5m Source Confirmation
  53. GRB 210919A CAHA 2.2m Observations: Afterglow/Host Galaxy Candidate
  54. GRB 210925A: GECAM detection
  55. GRB 210925A: Fermi GBM Final Real-time Localization
  56. GRB 210919A: Chandra rapid ToO upper limit
  57. GRB 210924A: Fermi GBM Final Real-time Localization
  58. GRB 210923B: GECAM detection
  59. Retraction of Fermi GBM GRB 210923A: the trigger is not a GRB
  60. IceCube-210922A: Upper limits from Fermi-GBM Observations
  61. GRB 210919A: DECam Upper Limits
  62. GRB 210923A: Fermi GBM Final Real-time Localization
  63. GRB 210919A: Swift-BAT refined analysis
  64. GRB 210912A: LBT optical observations
  65. GRB 210919A: Lowell Discovery Telescope upper limits (correction to GCN 30859)
  66. GRB 210919a: Lowell Discovery Telescope upper limits
  67. GRB210919A: Keck NIRC2 Kp band upper limits
  68. GRB 210919A: Swift/UVOT Upper Limits
  69. GRB 210919A: LOAO and LSGT optical upper limits
  70. GRB 210919A: MITSuME Akeno optical upper limits
  71. GRB 210919A: Swift-XRT refined Analysis
  72. GRB 210919B: Fermi GBM Final Real-time Localization
  73. GRB 210919A: NOT upper limits
  74. GRB 210919A: AbAO optical upper limit
  75. GRB 210919A: Enhanced Swift-XRT position
  76. GRB 210919A: LCO Optical Upper Limit
  77. GRB 210919A: BOOTES-2/TELMA optical upper limit
  78. Swift GRB 210919A: Global MASTER-Net observations report
  79. GRB 210919A: Swift detection of a short burst
  80. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  81. GRB 210917A: Fermi GBM Final Real-time Localization
  82. GRB 210812A is not a compelling example of a lensed GRB
  83. GRB 210909A: Detection by GRBAlpha
  84. GRB 210912A: Swift-BAT refined analysis
  85. GRB 210912A: Tautenburg observations
  86. GRB 210912A: CAHA 2.2m Detection
  87. GRB 210912A: Swift-XRT refined Analysis
  88. GRB 210912A: Swift/UVOT Detection
  89. GRB 210912A: Enhanced Swift-XRT position
  90. GRB 210912A: Host-galaxy candidate in PanSTARRS
  91. GRB 210912A: Mondy optical afterglow confirmation
  92. Swift GRB 210912A: Global MASTER-Net observations report
  93. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  94. GRB 210912B: Fermi GBM Final Real-time Localization
  95. GRB 210912A: Swift detection of a burst
  96. GRB 210826A: further Swift-XRT observations
  97. GRB 210909B: GECAM detection
  98. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  99. Fermi GRB 210909A: Global MASTER-Net observations report
  100. GRB 210909A: Fermi GBM Final Real-time Localization

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