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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"

32688 results found.

  1. IPN triangulation of GRB 250516B
  2. GRB 250520A: J-band observations with WINTER
  3. GRB 250520A: Gemini-South optical observations
  4. GRB 250520A: REM optical/NIR early observations
  5. GRB 250520A:SVOM/VT optical candidate
  6. GRB 250520A: COLIBRÍ optical upper limit
  7. GRB 250520A: DDOTI Optical Upper Limit
  8. GRB 250520A: AstroSat CZTI detection of a short burst
  9. GRB 250516B: GRBAlpha detection
  10. GRB 250520A: SVOM/GRM observation
  11. GRB 250520A: GOTO optical upper limit
  12. GRB 250516B: Insight-HXMT detection
  13. EP250427a/GRB250427A: VLA Detection of Radio Counterpart
  14. GRB 250516A: Swift-BAT refined analysis
  15. GRB 250516A: COLIBRÍ optical upper limit
  16. Konus-Wind detection of GRB 250516A
  17. GRB 250516B: NuSTAR Detection of the Prompt Emission
  18. Fermi GRB 250516A: Global MASTER-Net observations report
  19. GRB 250515A: Swift-XRT observations
  20. GRB 250515A: NOT classification of GOTO25cqo as a type-Ia SN
  21. GRB 250515A:COLIBRÍ optical observations of the GOTO candidate
  22. Swift GRB 250516A: Global MASTER-Net observations report
  23. GRB 250515A: 1.6m Mephisto optical detection
  24. GRB 250516A: AstroSat CZTI detection
  25. GRB 250515A/GOTO25cqo: SVOM/VT optical blue color
  26. GRB 250516A: Fermi GBM Observation
  27. GRB 250516A: Swift/UVOT Detection
  28. GRB 250515A: Swift ToO observations
  29. GRB 250512B / EP250512a: SVOM/GRM analysis
  30. GRB 250515A: GOTO candidate optical counterpart
  31. GRB 250424A: COLIBRÍ detection of the associated supernova
  32. Konus-Wind detection of GRB 250512B / EP250512a
  33. GRB 250502A: TESS observations
  34. GRB 250509A: Swift-BAT refined analysis
  35. LIGO/Virgo/KAGRA S250328ae: DECam DESGW Candidates (Final Epochs)
  36. Fermi GRB 250512A: Global MASTER-Net observations report
  37. Konus-Wind detection of GRB 250506A
  38. EP250512a/GRB 250512B: REM optical/NIR observations
  39. EP250511a: Koshka Zeiss-1000 Optical Upper Limit
  40. GRB 250507B: AstroSat CZTI detection
  41. EP250511a: Gemini optical counterpart observation
  42. EP250512a/GRB 250512B refined analysis of the EP-WXT and EP-FXT observations
  43. EP250512a/GRB 250512B: FTW optical and NIR observations of the counterpart
  44. EP250512a: Global MASTER-Net observations report
  45. EP250511a: FTW optical and NIR observations
  46. GRB 250512B/EP250512a: SVOM/VT optical fading
  47. GRB 250512B/EP250512a:SVOM/VT bright optical counterpart
  48. EP250511a: Mephisto optical upper limits
  49. GRB 250506A: GRBAlpha detection
  50. GRB 250512B: SVOM detection of a burst
  51. EP250511a: REM optical/NIR observations
  52. EP250511a: Einstein Probe follow-up obsevation and refined analysis
  53. EP250511a: SVOM/VT optical candidate comfirmation
  54. EP250511a: Global MASTER-Net observations report
  55. EP250511a: COLIBRÍ optical counterpart candidate
  56. EP250511a: BOOTES-5 optical upper limit
  57. EP250508a: Gemini NIR upper limits
  58. GRB 250510B: Fermi GBM Observation
  59. Fermi GRB 250510C: Global MASTER-Net observations report
  60. Fermi GRB 250510B: Global MASTER-Net observations report
  61. GRB 250510A: Swift-XRT observations
  62. GRB 250509A: Fermi GBM Observation
  63. IceCube-250506A: No Transient Candidates from the Zwicky Transient Facility
  64. GRB 250510A: follow-up observation with EP-FXT
  65. GRB 250510B: Swift/BAT-GUANO localization skymap of a burst
  66. GRB 250510A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  67. GRB 250507A: J-band observations with WINTER (duplicate submission)
  68. GRB 250507A: J-band observations with WINTER
  69. EP250508a: SVOM/VT optical candidate fading
  70. Fermi GRB 250509A: Global MASTER-Net observations report
  71. Swift GRB 250509A: Global MASTER-Net observations report
  72. GRB 250506A: NOT optical upper limits
  73. EP250508a: Liverpool Telescope optical upper limits
  74. EP250508a: follow-up observation with EP-FXT
  75. EP250508a: SVOM/VT optical candidate
  76. EP250508a: KAIT optical upper limit
  77. GRB 250507A: KAIT optical upper limit
  78. EP250508a: refined analysis of the EP-WXT and EP-FXT observations
  79. GRB 250502A: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  80. GRB 250506A: GECAM detection
  81. EP250508a: REM optical/NIR observations
  82. EP250508a: Global MASTER-Net observations report
  83. GRB 250506A: SVOM/VT optical upper limit
  84. EP250508a: COLIBRÍ Optical Limit
  85. GRB 250507A: Swift-XRT refined Analysis
  86. IceCube-250506A: Upper limits from a search for additional neutrino events in IceCube
  87. GRB 250506A: Swift/UVOT Upper Limits
  88. GRB 250507A: follow-up observation with EP-FXT
  89. GRB 250430A / EP250430a: AstroSat CZTI detection
  90. EP#01709175213/IGR J19566+0326: Swift-XRT detection
  91. GRB 250506A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  92. GRB 250507A: refined SVOM/MXT data analysis
  93. GRB 250507A: REM optical/NIR observations
  94. GRB 250507A: SVOM/VT optical upper limit
  95. GRB 250506A: Swift-XRT observations
  96. Fermi-LAT Gamma-ray Observations of IceCube-250506A
  97. GRB 250507A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  98. GRB 250506A: Mephisto optical upper limits
  99. GRB 250504A: EIRSAT-1 GMOD Detection
  100. GRB 250506A: Swift ToO observations

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