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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"

28118 results found.

  1. EP250404a: Nanshan 0.43m Telescope optical observatios
  2. GRB 250411A: Fermi GBM Final Real-time Localization
  3. GRB 250407A: Continued KAIT/Nickel optical observations
  4. GRB 250320B: cubesat Avion detection
  5. IceCube-250406A: Swift-XRT observations
  6. IPN triangulation of GRB 250407A
  7. GRB 250407A: LCO detection of a fading optical counterpart
  8. EP250407a: Swift-XRT observations
  9. Konus-Wind detection of GRB 250407A
  10. GRB 250407A: SVOM/GRM observation of a bright long burst
  11. GRB 250407A: EP-WXT afterglow detection
  12. EP250407a: EP-WXT detection of a fast X-ray transient
  13. GRB 250407A: COLIBRÍ/DDRAGO Detection of the Optical Counterpart
  14. GRB 250407A: KAIT Optical Afterglow Candidate
  15. GRB 250407A: Fermi GBM Detection
  16. GRB 250407A: Swift-XRT afterglow detection
  17. GRB 250407A: Swift ToO observations
  18. GRB 250407A: SRG/ART-XC afterglow detection
  19. Konus-Wind detection of GRB 250406B (short/hard)
  20. GRB 250407A: Fermi GBM Final Real-time Localization
  21. IceCube-250406A - IceCube observation of a high-energy neutrino candidate track-like event
  22. IceCube 250406.951: COLIBRÍ/DDRAGO Optical Upper Limit
  23. GRB 250406A: AstroSat CZTI detection
  24. GRB 250406A: Fermi GBM Final Real-time Localization
  25. EP250404a / GRB 250404A: Montarrenti Observatory optical observations
  26. GRB 250404A / EP250404a: SVOM/GWAC-F60 and F50 observations
  27. EP250404a / GRB 250404A: J band observations by SYSU 80cm telescope
  28. Konus-Wind detection of GRB 250404A / EP250404a
  29. GRB 250404A / EP250404a: Leavitt Observatory optical counterpart detection
  30. GRB 250331D: Swift-XRT afterglow detection
  31. GRB 250404B: AstroSat CZTI detection of a short burst
  32. GRB 250403A: AstroSat CZTI detection
  33. EP250404a: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  34. EP250404a: REM optical/NIR observations
  35. EP250404a: Seimei/TriCCS optical counterpart detection
  36. EP250404A / GRB250404A: Ondrejov D50 optical afterglow detection
  37. EP250404a: LCO optical counterpart detection
  38. GRB 250403A: Montarrenti Observatory optical detection
  39. GRB 250404A: Fermi GBM Detection
  40. GRB 250403A: KAIT optical observations
  41. EP250404a: AKO Optical Afterglow Detection
  42. EP250404a: LAST detection of optical counterpart
  43. GRB 250402A: Swift/BAT-GUANO localization skymap of a burst
  44. EP250404a: Xinglong-2.16m spectroscopic redshift
  45. GRB 250327B: VIRT Optical Upper Limit
  46. EP250404a: Mephisto multi-band optical detection
  47. EP250321A: J band upper limit by SYSU 80cm telescope
  48. EP250404a: BOOTES-4/JGT optical afterglow detection
  49. EP250404a: Nanshan/HMT optical counterpart detection
  50. EP250404a: Einstein Probe detection of an X-ray transient
  51. GRB 250404A: Fermi GBM Final Real-time Localization
  52. GRB 250403A: Swift/UVOT Detection
  53. GRB 250402A: Swift/UVOT Upper Limits
  54. GRB 250403A: SVOM/VT optical observation
  55. GRB 250403A: REM NIR afterglow detection
  56. GRB 250403A: LCO optical counterpart detection
  57. IceCube-250330A: MASTER detection of PKS 2032+107 blazar flare with Zhirkov effect
  58. GRB 250403A: JinShan optical observations
  59. GRB 250402A: EP-FXT afterglow detection
  60. GRB 250403A: Optical counterpart detection by LCO.
  61. GRB 250403A: Swift-XRT observations
  62. GRB 250322A: 10 GHz VLA radio upper limits
  63. GRB 250403A: 1.6m Mephisto multi-band optical detection
  64. GRB 250403A: GOTO detection of the optical afterglow
  65. GRB 250402A: Swift-XRT observations
  66. GRB 250403A : SVOM detection of a burst
  67. GRB 250403A: Fermi GBM Final Real-time Localization
  68. GRB 250225B: VLT host galaxy redshift z = 0.950
  69. GRB250402A: SVOM/COLIBRÍ (FM-GFT) Detection of the Optical Counterpart
  70. GRB 250402A: VLT/FORS2 spectroscopic redshift z = 2.823
  71. GRB 250402A: REM optical/NIR upper limits
  72. GRB 250402A: LCO optical counterpart detection
  73. GRB 250402A: refined SVOM/MXT data analysis
  74. EP250402a: Einstein Probe detection of a fast X-ray transient
  75. GRB 250402B: AstroSat CZTI detection of a short burst
  76. GRB 250402A: SVOM detection of a burst
  77. GRB 250314A: ALMA detection
  78. GRB 250329B: Swift/UVOT Upper Limit
  79. GRB 250329A: Swift/UVOT Upper Limit
  80. GRB 250327B: Swift/UVOT Detection
  81. GRB 250327A: Swift/UVOT Upper Limits
  82. GRB 250327B: Kilonova-Catcher Observations
  83. GRB250331D: AbAO optical observations
  84. GRB 250331C: Swift/UVOT Upper Limits
  85. GRB 250331B: Swift/UVOT Upper Limits
  86. GRB 250328A: AbAO AS-32 Optical Observations
  87. GRB 250219A: NOT candidate host galaxy detection
  88. GRB 250322B: GRBAlpha detection
  89. GRB 250331D: Swift-XRT observations
  90. GRB 250331C: Swift-XRT refined Analysis
  91. GRB 250331B: Swift-XRT refined Analysis
  92. GRB 250331B: Swift-XRT refined Analysis
  93. GRB 250322B possible detection by the AstroSat Satellite
  94. LIGO/Virgo/KAGRA S250328ae: DECam DESGW Candidates (Epoch 2)
  95. GRB 250330B: EIRSAT-1 GMOD Detection
  96. GRB 250331E: Fermi GBM Final Real-time Localization
  97. GRB 250329B: CAHA 2.2m telescope optical limit
  98. GRB 250331D: Swift ToO observations
  99. GRB 250331D: Swift/BAT-GUANO arcminute localization of a burst during slew
  100. Konus-Wind detection of GRB 250327B

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