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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"

28262 results found.

  1. GRB 221009A: MITSuME Okayama optical observation
  2. GRB 221009A: GMG observation
  3. GRB 221013B: Fermi GBM Final Real-time Localization
  4. GRB 221013A: Fermi GBM Final Real-time Localization
  5. Afterglow limits of GRB 221006A from OHP
  6. GRB221009A: optical afterglow measurements from Konkoly Observatory
  7. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  8. INTEGRAL detection of a burst from SGR J1935+2154
  9. GRB 220829A: Detection by GRBAlpha
  10. GRB 220826B: Detection by GRBAlpha
  11. GRB 221009A: NuSTAR Detection
  12. GRB 221009A: LCOGT Optical Afterglow Detection
  13. GRB 221009A: COATLI Detection of the Afterglow
  14. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  15. GRB 221009A: 10.4m GTC spectroscopic redshift confirmation
  16. GRB 221009A: Detection by GRBAlpha
  17. GRB 221009A: Sintez-Newton/CrAO optical observations
  18. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  19. GRB 221006A: Swift ToO observations
  20. GRB 221011A: Fermi GBM Final Real-time Localization
  21. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  22. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  23. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  24. GRB 221009A: NOEMA mm detection
  25. INTEGRAL detection of a burst from SGR J1935+2154
  26. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  27. GRB 221009A: Continued Swift/XRT observations
  28. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  29. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  30. Konus-Wind detection of GRB 221009A
  31. Swift J1913.1+1946: New Photometry
  32. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  33. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  34. ​GRB 221009A: Multi-color detection of the optical
  35. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection
  36. GRB 221009: Swift/UVOT Detection
  37. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  38. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  39. GRB 221009A: REM optical and NIR detection of the afterglow
  40. GRB 221009A: Swift-XRT refined Analysis
  41. GRB 221009A (Swift J1913.1+1946): AGILE/MCAL detection
  42. Swift J1913.1+1946: Early Optical Photometry
  43. GRB 221009A: Redshift from X-shooter/VLT
  44. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  45. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  46. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  47. IPN triangulation of extremely bright GRB 221009A
  48. Swift J1913.1+1946: Optical photometry
  49. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  50. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  51. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  52. GRB 221009A: Swift detected transient may be GRB
  53. Swift GRB221009.59: Global MASTER-Net OT detection
  54. GRB 221008A: Swift-XRT observations
  55. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  56. GRB 221008A: Tiled Swift observations
  57. GRB 221008A: MAXI/GSC detection
  58. GRB 220915A: Detection by GRBAlpha
  59. GRB 221006A: Swift-XRT observations
  60. GRB 221006A: Tiled Swift observations
  61. GRB 221006A: MAXI/GSC detection
  62. GRB 220930A: MITSuME Akeno optical upper limits
  63. GRB 220912A: Detection by VZLUSAT-2
  64. GRB220927A: Detection by GRBAlpha
  65. GRB 220921A: ATCA detection of radio counterpart
  66. GRB 220930A: AbAO Optical Upper Limit
  67. Konus-Wind detection of GRB 220930A
  68. GRB 220930A: AstroSat CZTI detection
  69. GRB 220930A: Swift-XRT refined Analysis
  70. GRB 220930A: LCOGT Optical Upper Limits
  71. GRB 220930A: Swift/UVOT Upper Limits
  72. GRB 220930A: Enhanced Swift-XRT position
  73. GRB 220930A: BOOTES-5/JGT early optical upper limit
  74. GRB 220930A: Prompt enhanced Swift-XRT position
  75. GRB 220930A: COATLI Upper Limits
  76. GRB 220930A: Swift detection of a burst
  77. Konus-Wind detection of GRB 220927A
  78. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  79. IPN triangulation of GRB 220927A (long)
  80. GRB 220921A: LCOGT Optical Observations
  81. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  82. GRB 220927A: Fermi GBM Final Localization
  83. GRB 220924A: Fermi GBM detection
  84. Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
  85. GRB 220926A: Swift detection of a burst
  86. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  87. GRB 220921A: further MeerLICHT observations
  88. GRB 220925A: Fermi GBM Final Real-time Localization
  89. GRB 220924A: Fermi GBM Final Real-time Localization
  90. GRB 220921A: ALMA detection
  91. GRB 220921A: DDOTI Detection of the Afterglow
  92. Konus-Wind detection of GRB 220921A
  93. GRB 220921A: Fermi GBM detection
  94. GRB 220921A: MeerLICHT afterglow observations
  95. GRB 220921A: Swift-XRT Observations
  96. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  97. GRB 220921A: Fermi-LAT detection
  98. GRB 220921A: Tiled Swift observations
  99. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  100. IceCube-220918A - IceCube observation of a high-energy neutrino candidate track-like event

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