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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"

39461 results found.

  1. Konus-Wind detection of GRB 210928A
  2. Fermi trigger No 654854799: Global MASTER-Net observations report
  3. Correction to GCN 30915: GRB 210928A: Swift-XRT analysis
  4. GRB 210928A: Kinder SLT-40cm optical limits
  5. GRB 210930A: Swift-BAT refined analysis
  6. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  7. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  8. GRB 210928A: Swift-XRT refined Analysis
  9. GRB 210928A: Fermi GBM observation
  10. GRB 210928A: Fermi-LAT detection
  11. GRB 210927B: GECAM detection
  12. GRB 210930A: CAHA 2.2m telescope optical limit
  13. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  14. Fermi trigger No 654739449: Global MASTER-Net observations report
  15. Swift GRB211001.03: Global MASTER-Net observations report
  16. Swift Trigger 1076121 is not a GRB
  17. Swift GRB211001.03: Global MASTER-Net OT detection
  18. GRB 210930A: Swift/UVOT Upper Limits
  19. GRB 210930A: Swift-XRT refined Analysis
  20. Swift GRB 210930A: Global MASTER-Net observations report
  21. GRB 210930A: Enhanced Swift-XRT position
  22. Fermi trigger No 654658271: Global MASTER-Net observations report
  23. Fermi GRB 210929B: Global MASTER-Net observations report
  24. GRB 210930A: Swift detection of a burst
  25. GRB 210929B: Fermi GBM Final Real-time Localization
  26. Fermi-LAT Gamma-ray Observations of IceCubeCascade-210926A
  27. GRB 210929A: Fermi GBM Final Real-time Localization
  28. GRB 210927A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 654396242)
  29. GRB 210925B: AstroSat CZTI detection
  30. IPN triangulation of GRB 210925B
  31. GRB 210926A: AstroSat CZTI detection
  32. GRB 210919A: iTelescope T-11 upper limits
  33. GRB 210926A: GECAM detection
  34. GRB 210927A: Fermi GBM Final Real-time Localization
  35. GRB 210919A OSN 1.5m Source Confirmation
  36. GRB 210919A CAHA 2.2m Observations: Afterglow/Host Galaxy Candidate
  37. GRB 210925A: GECAM detection
  38. GRB 210925A: Fermi GBM Final Real-time Localization
  39. GRB 210919A: Chandra rapid ToO upper limit
  40. GRB 210924A: Fermi GBM Final Real-time Localization
  41. GRB 210923B: GECAM detection
  42. Retraction of Fermi GBM GRB 210923A: the trigger is not a GRB
  43. IceCube-210922A: Upper limits from Fermi-GBM Observations
  44. GRB 210919A: DECam Upper Limits
  45. Fermi-LAT Gamma-ray Observations of IceCube-210922A
  46. GRB 210923A: Fermi GBM Final Real-time Localization
  47. IceCube Alert 210922.76: Global MASTER-Net observations report
  48. GRB 210919A: Swift-BAT refined analysis
  49. GRB 210912A: LBT optical observations
  50. GRB 210919A: Lowell Discovery Telescope upper limits (correction to GCN 30859)
  51. GRB 210919a: Lowell Discovery Telescope upper limits
  52. GRB210919A: Keck NIRC2 Kp band upper limits
  53. GRB 210919A: Swift/UVOT Upper Limits
  54. GRB 210919A: LOAO and LSGT optical upper limits
  55. GRB 210919A: MITSuME Akeno optical upper limits
  56. GRB 210919A: Swift-XRT refined Analysis
  57. GRB 210919B: Fermi GBM Final Real-time Localization
  58. GRB 210919A: NOT upper limits
  59. GRB 210919A: AbAO optical upper limit
  60. GRB 210919A: Enhanced Swift-XRT position
  61. GRB 210919A: LCO Optical Upper Limit
  62. GRB 210919A: BOOTES-2/TELMA optical upper limit
  63. Swift GRB 210919A: Global MASTER-Net observations report
  64. GRB 210919A: Swift detection of a short burst
  65. Swift trigger 1073821: detection of IGR J16418-4532
  66. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  67. GRB 210917A: Fermi GBM Final Real-time Localization
  68. GRB 210812A is not a compelling example of a lensed GRB
  69. GRB 210909A: Detection by GRBAlpha
  70. GRB 210912A: Swift-BAT refined analysis
  71. GRB 210912A: Tautenburg observations
  72. GRB 210912A: CAHA 2.2m Detection
  73. GRB 210912A: Swift-XRT refined Analysis
  74. GRB 210912A: Swift/UVOT Detection
  75. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  76. GRB 210912A: Enhanced Swift-XRT position
  77. GRB 210912A: Host-galaxy candidate in PanSTARRS
  78. Fermi trigger No 653151835: Global MASTER-Net observations report
  79. Fermi trigger No 653124492: Global MASTER-Net observations report
  80. Fermi trigger No 653122278: Global MASTER-Net observations report
  81. GRB 210912A: Mondy optical afterglow confirmation
  82. Swift GRB 210912A: Global MASTER-Net observations report
  83. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  84. GRB 210912B: Fermi GBM Final Real-time Localization
  85. GRB 210912A: Swift detection of a burst
  86. Fermi trigger No 653093506: Global MASTER-Net observations report
  87. Fermi trigger No 653066776: Global MASTER-Net observations report
  88. Fermi trigger No 653084584: Global MASTER-Net observations report
  89. Fermi trigger No 653083551: Global MASTER-Net observations report
  90. Fermi trigger No 653079281: Global MASTER-Net observations report
  91. Fermi trigger No 653066130: Global MASTER-Net observations report
  92. Fermi trigger No 653072474: Global MASTER-Net observations report
  93. Fermi trigger No 653071808: Global MASTER-Net observations report
  94. Fermi trigger No 653054042: Global MASTER-Net observations report
  95. Fermi trigger No 653049776: Global MASTER-Net observations report
  96. Fermi trigger No 653022153: Global MASTER-Net observations report
  97. Fermi trigger No 653031163: Global MASTER-Net observations report
  98. Swift GRB210910.42: Global MASTER-Net observations report
  99. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  100. Fermi trigger No 653010039: Global MASTER-Net observations report

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