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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"

27949 results found.

  1. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  2. GRB 211023A: Fermi GBM Final Real-time Localization
  3. IceCube-211023A - IceCube observation of a high-energy neutrino candidate track-like event
  4. IPN Triangulation of GRB 210927B
  5. GRB 211022A: GECAM detection
  6. AMON IC_HAWC NuEm-211020A: No neutrino counterpart detected with ANTARES
  7. GRB 211018A: Swift ToO observations
  8. BepiColombo MGNS joins the IPN
  9. GRB 211019A: Detection by GRBAlpha
  10. GRB 211018A: Detection by GRBAlpha
  11. GRB 211018A: Fermi-LAT detection
  12. GRB 211019A: Fermi GBM Final Real-time Localization
  13. Swift GRB211017.99: Global MASTER-Net observations report
  14. Swift trigger 1078701: MITSuME Akeno optical upper limits
  15. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  16. Swift GRB211010.45: Global MASTER-Net observations report
  17. Swift Trigger 1078701 is probably not a GRB
  18. IceCube-20210922A: DESNU Optical counterpart candidate from 5 nights of DECam observations
  19. GRB 210928A: MeerKAT detection
  20. Konus-Wind detection of GRB 210928A
  21. Correction to GCN 30915: GRB 210928A: Swift-XRT analysis
  22. GRB 210928A: Kinder SLT-40cm optical limits
  23. GRB 210930A: Swift-BAT refined analysis
  24. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  25. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  26. GRB 210928A: Swift-XRT refined Analysis
  27. GRB 210928A: Fermi-LAT detection
  28. Swift GRB211001.03 / trigger 1076121 : MASTER OT retraction
  29. GRB 210927B: GECAM detection
  30. GRB 210930A: CAHA 2.2m telescope optical limit
  31. Swift GRB211001.03: Global MASTER-Net observations report
  32. Swift Trigger 1076121 is not a GRB
  33. Swift GRB211001.03: Global MASTER-Net OT detection
  34. GRB 210930A: Swift/UVOT Upper Limits
  35. GRB 210930A: Swift-XRT refined Analysis
  36. Swift GRB 210930A: Global MASTER-Net observations report
  37. GRB 210930A: Enhanced Swift-XRT position
  38. GRB 210930A: Swift detection of a burst
  39. GRB 210929B: Fermi GBM Final Real-time Localization
  40. GRB 210929A: Fermi GBM Final Real-time Localization
  41. GRB 210927A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 654396242)
  42. GRB 210925B: AstroSat CZTI detection
  43. IPN triangulation of GRB 210925B
  44. GRB 210926A: AstroSat CZTI detection
  45. GRB 210919A: iTelescope T-11 upper limits
  46. IceCube-210926A: No neutrino counterpart candidates in ANTARES search
  47. GRB 210926A: GECAM detection
  48. GRB 210927A: Fermi GBM Final Real-time Localization
  49. GRB 210919A OSN 1.5m Source Confirmation
  50. GRB 210919A CAHA 2.2m Observations: Afterglow/Host Galaxy Candidate
  51. GRB 210925A: GECAM detection
  52. GRB 210925A: Fermi GBM Final Real-time Localization
  53. GRB 210924A: Fermi GBM Final Real-time Localization
  54. IceCube-210922A: No Candidate Counterparts from Swift/XRT follow up observations
  55. IceCube-210922A: No significant detection in HAWC
  56. IceCube-210922A: No neutrino counterpart candidates in ANTARES search
  57. GRB 210923B: GECAM detection
  58. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  59. GRB 210923A: Fermi GBM Final Real-time Localization
  60. GRB 210919A: Swift-BAT refined analysis
  61. IceCube-210922A - IceCube observation of a high-energy neutrino candidate track-like event
  62. GRB 210919A: Lowell Discovery Telescope upper limits (correction to GCN 30859)
  63. GRB 210919A: Swift/UVOT Upper Limits
  64. GRB 210919A: MITSuME Akeno optical upper limits
  65. GRB 210919A: Swift-XRT refined Analysis
  66. GRB 210919B: Fermi GBM Final Real-time Localization
  67. GRB 210919A: AbAO optical upper limit
  68. GRB 210919A: Enhanced Swift-XRT position
  69. GRB 210919A: LCO Optical Upper Limit
  70. GRB 210919A: BOOTES-2/TELMA optical upper limit
  71. Swift GRB 210919A: Global MASTER-Net observations report
  72. GRB 210919A: Swift detection of a short burst
  73. Swift trigger 1073821: detection of IGR J16418-4532
  74. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  75. GRB 210917A: Fermi GBM Final Real-time Localization
  76. GRB 210909A: Detection by GRBAlpha
  77. GRB 210912A: Swift-BAT refined analysis
  78. GRB 210912A: CAHA 2.2m Detection
  79. GRB 210912A: Swift-XRT refined Analysis
  80. GRB 210912A: Swift/UVOT Detection
  81. GRB 210912A: Enhanced Swift-XRT position
  82. GRB 210912A: Host-galaxy candidate in PanSTARRS
  83. Swift GRB 210912A: Global MASTER-Net observations report
  84. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  85. GRB 210912B: Fermi GBM Final Real-time Localization
  86. GRB 210912A: Swift detection of a burst
  87. Swift GRB210910.42: Global MASTER-Net observations report
  88. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  89. IPN triangulation of a bright burst from SGR 1935+2154
  90. GRB 210826A: further Swift-XRT observations
  91. GRB 210909B: GECAM detection
  92. Swift detection of a burst from SGR Swift J1555.2-5402
  93. GRB 210909A: Fermi GBM Final Real-time Localization
  94. GRB 210905A: Swift/UVOT Upper Limits
  95. GRB 210905A: ATCA detection
  96. GRB 210905A: ALMA detection
  97. GRB 210905A: AstroSat CZTI detection
  98. GRB 210905A, GROND observations
  99. Konus-Wind detection of GRB 210905A
  100. Fermi GBM Sub-Threshold Detection of GRB 210905A

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