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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"

19724 results found.

  1. GRB 221009A: IXPE preliminary upper limits of X-ray polarization
  2. GRB 221009A: OHP optical observations
  3. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  4. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  5. GRB 221006A: Swift-XRT afterglow detection
  6. GRB 221009A: MITSuME Okayama optical observation
  7. GRB 221009A: Sayan observatory 1.6-m telescope observations
  8. GRB 221009A: GMG observation
  9. Afterglow limits of GRB 221006A from OHP
  10. GRB221009A: optical afterglow measurements from Konkoly Observatory
  11. GRB 221009A/Swift J1913.1+1946: SMA observations
  12. INTEGRAL shows increasing activity in SGR J1935+2154
  13. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  14. INTEGRAL detection of a burst from SGR J1935+2154
  15. GRB 221009A: NICER follow-up observations
  16. GRB 221009A: LCOGT Optical Afterglow Detection
  17. GRB 221009A: COATLI Detection of the Afterglow
  18. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  19. GRB 221006A: Swift ToO observations
  20. GRB 221009A: BlackGEM optical observations
  21. INTEGRAL detection of a burst from SGR J1935+2154
  22. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  23. GRB 221009A: Lulin SLT-40cm optical observations
  24. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  25. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  26. GRB 221009: Swift/UVOT Detection
  27. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  28. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  29. GRB 221009A/Swift J1913.1+1946: AMI-LA observations
  30. GRB 221009A: REM optical and NIR detection of the afterglow
  31. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  32. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  33. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  34. Swift J1913.1+1946: Optical photometry
  35. GRB 221008A: Swift-XRT observations
  36. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  37. GRB 221008A: Tiled Swift observations
  38. GRB 221006A: Tiled Swift observations
  39. GRB 220930A: MITSuME Akeno optical upper limits
  40. GRB220927A: Detection by GRBAlpha
  41. GRB 220930A: AbAO Optical Upper Limit
  42. GRB 220930A: AstroSat CZTI detection
  43. GRB 220930A: LCOGT Optical Upper Limits
  44. GRB 220930A: Swift/UVOT Upper Limits
  45. GRB 220930A: Enhanced Swift-XRT position
  46. GRB 220930A: COATLI Upper Limits
  47. GRB 220930A: Swift detection of a burst
  48. IPN triangulation of GRB 220927A (long)
  49. GRB 220921A: LCOGT Optical Observations
  50. GRB 220926A: Swift detection of a burst
  51. GRB 220921A: further MeerLICHT observations
  52. GRB 220921A: DDOTI Detection of the Afterglow
  53. Konus-Wind detection of GRB 220921A
  54. GRB 220921A: MeerLICHT afterglow observations
  55. GRB 220921A: Tiled Swift observations
  56. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  57. IceCube-220907A: No significant detection in HAWC
  58. GRB 220910A: Fermi GBM observation
  59. IPN triangulation of GRB 220905A
  60. GRB 220909A: Swift ToO observations
  61. GRB 220910A: AstroSat CZTI detection
  62. GRB 220907A: Swift-BAT refined analysis
  63. IPN triangulation of GRB 220903A (long)
  64. GRB 220907A: Nanshan/NEXT optical upper limits
  65. GRB 220907A: Swift/UVOT Upper Limits
  66. GRB 220907A: Swift-XRT refined Analysis
  67. GRB 220831A: ATCA 5/9 GHz radio observations
  68. Fermi-LAT Gamma-ray Observations of IceCube-220907A
  69. GRB 220907A: Swift detection of a burst
  70. GRB 220831A: DECam detection of a possible optical counterpart
  71. GRB 220831A: Fermi GBM observation
  72. GRB 220831A: Swift-XRT observations
  73. GRB 220831A: Swift ToO observations
  74. IceCube-220822A: No significant detection in HAWC
  75. GRB 220826A: Lesedi optical afterglow detection
  76. GRB 220826A: Swift/UVOT Detection
  77. GRB 220826A: iTelescope optical afterglow observations
  78. GRB 220826A: Enhanced Swift-XRT position
  79. GRB 220826A: Swift detection of a burst with an optical counterpart
  80. Fermi-LAT gamma-ray observations of IceCube-220822A and detection of a new gamma-ray source, Fermi J1810.1+2154
  81. GRB 220813A: VLT optical observations and possible host galaxy
  82. GRB 220813A: Swift/UVOT Detection
  83. GRB 220810A: Further Swift-XRT observations
  84. GRB 220813A: Swift-XRT refined Analysis
  85. GRB 220813A: Enhanced Swift-XRT position
  86. GRB 220813A: Swift detection of a burst with an optical counterpart
  87. GRB 220810A: Swift-XRT observations
  88. GRB 220810A: Swift ToO observations
  89. GRB 220810A: MeerLICHT detection of two afterglow candidates
  90. Fermi GBM trigger 681633544/220808277 is not a GRB
  91. GRB 220803A: AstroSat CZTI detection
  92. GRB 220730A: Swift-XRT afterglow detection
  93. GRB 220730A: Swift/UVOT Upper Limits
  94. GRB 220730A: Swift-XRT observations
  95. GRB 220730A: Swift detection of a short hard burst
  96. GRB 220715B: VIRT Optical Upper Limit
  97. GRB220714B: UVOT detections
  98. GRB 220715B: Swift/UVOT Upper Limits
  99. GRB 220715B: Enhanced Swift-XRT position
  100. GRB 220715B: Swift detection of a burst

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