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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"

28275 results found.

  1. GRB 221009A: HEBS detection
  2. GRB 221009A: Gemini-South Infrared Afterglow Detection
  3. GRB221009A: Gemini-South Optical Afterglow Detection
  4. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  5. GRB 221014A: Fermi GBM Final Real-time Localization
  6. GRB 221009A: Gamma-ray Detection by SIRI-2
  7. GRB221009A: Ionospheric disturbance observed in India
  8. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  9. MAXI GRB 221006A: Redshifts of the possible host galaxies
  10. GRB 221009A: search for neutrinos with KM3NeT
  11. GRB 221009A: MeerKAT detection
  12. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  13. GRB 221006A: Swift-XRT afterglow detection
  14. GRB 221009A: MITSuME Okayama optical observation
  15. GRB 221009A: GMG observation
  16. GRB 221013B: Fermi GBM Final Real-time Localization
  17. GRB 221013A: Fermi GBM Final Real-time Localization
  18. Afterglow limits of GRB 221006A from OHP
  19. GRB221009A: optical afterglow measurements from Konkoly Observatory
  20. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  21. INTEGRAL detection of a burst from SGR J1935+2154
  22. GRB 220829A: Detection by GRBAlpha
  23. GRB 220826B: Detection by GRBAlpha
  24. GRB 221009A: NuSTAR Detection
  25. GRB 221009A: LCOGT Optical Afterglow Detection
  26. GRB 221009A: COATLI Detection of the Afterglow
  27. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  28. GRB 221009A: 10.4m GTC spectroscopic redshift confirmation
  29. GRB 221009A: Detection by GRBAlpha
  30. GRB 221009A: Sintez-Newton/CrAO optical observations
  31. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  32. GRB 221006A: Swift ToO observations
  33. GRB 221011A: Fermi GBM Final Real-time Localization
  34. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  35. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  36. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  37. GRB 221009A: NOEMA mm detection
  38. INTEGRAL detection of a burst from SGR J1935+2154
  39. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  40. GRB 221009A: Continued Swift/XRT observations
  41. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  42. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  43. Konus-Wind detection of GRB 221009A
  44. Swift J1913.1+1946: New Photometry
  45. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  46. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  47. ​GRB 221009A: Multi-color detection of the optical
  48. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection
  49. GRB 221009: Swift/UVOT Detection
  50. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  51. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  52. GRB 221009A: REM optical and NIR detection of the afterglow
  53. GRB 221009A: Swift-XRT refined Analysis
  54. GRB 221009A (Swift J1913.1+1946): AGILE/MCAL detection
  55. Swift J1913.1+1946: Early Optical Photometry
  56. GRB 221009A: Redshift from X-shooter/VLT
  57. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  58. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  59. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  60. IPN triangulation of extremely bright GRB 221009A
  61. Swift J1913.1+1946: Optical photometry
  62. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  63. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  64. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  65. GRB 221009A: Swift detected transient may be GRB
  66. Swift GRB221009.59: Global MASTER-Net OT detection
  67. GRB 221008A: Swift-XRT observations
  68. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  69. GRB 221008A: Tiled Swift observations
  70. GRB 221008A: MAXI/GSC detection
  71. GRB 220915A: Detection by GRBAlpha
  72. GRB 221006A: Swift-XRT observations
  73. GRB 221006A: Tiled Swift observations
  74. GRB 221006A: MAXI/GSC detection
  75. GRB 220930A: MITSuME Akeno optical upper limits
  76. GRB 220912A: Detection by VZLUSAT-2
  77. GRB220927A: Detection by GRBAlpha
  78. GRB 220921A: ATCA detection of radio counterpart
  79. GRB 220930A: AbAO Optical Upper Limit
  80. Konus-Wind detection of GRB 220930A
  81. GRB 220930A: AstroSat CZTI detection
  82. GRB 220930A: Swift-XRT refined Analysis
  83. GRB 220930A: LCOGT Optical Upper Limits
  84. GRB 220930A: Swift/UVOT Upper Limits
  85. GRB 220930A: Enhanced Swift-XRT position
  86. GRB 220930A: BOOTES-5/JGT early optical upper limit
  87. GRB 220930A: Prompt enhanced Swift-XRT position
  88. GRB 220930A: COATLI Upper Limits
  89. GRB 220930A: Swift detection of a burst
  90. Konus-Wind detection of GRB 220927A
  91. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  92. IPN triangulation of GRB 220927A (long)
  93. GRB 220921A: LCOGT Optical Observations
  94. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  95. GRB 220927A: Fermi GBM Final Localization
  96. GRB 220924A: Fermi GBM detection
  97. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  98. GRB 220926A: Swift detection of a burst
  99. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  100. GRB 220921A: further MeerLICHT observations

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