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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"

27123 results found.

  1. GRB 250702B,D,E / EP250702a: 10 GHz detection with the VLA
  2. GRB 250709A: Fermi GBM Final Localization
  3. EP/WXT 01709181970: GOTO observations confirm stellar variability
  4. EP-WXT trigger 01709181970. confirmation of a stellar flare by BOOTES-6
  5. The EP-WXT trigger 01709181970 is likely a flaring star
  6. Fermi GRB 250708A: Global MASTER-Net observations report
  7. IceCube-250708A: Global MASTER-Net observations report
  8. GRB 250708A: Fermi GBM Final Real-time Localization
  9. GRB 250706B/C: Konus-Wind analysis of the prompt emission
  10. GRB 250706B: SVOM observations interpreted as the afterglow of GRB 250706C
  11. GRB 250704B: CALET Gamma-Ray Burst Monitor detection
  12. GRB 250706B/C: VLT/X-shooter redshift z = 0.942
  13. IceCube-250706A: EP-FXT follow-up observations
  14. GRB 250706B/C: Fermi-LAT detection
  15. IceCube-250706A: Global MASTER-Net observations report
  16. GRB 250704A: SVOM/COLIBRÍ (FM-GFT) optical observations
  17. EP250702a/GRB250702 B,D,E: GRANDMA Upper Limit
  18. GRB 250706B: Swift/UVOT Detection
  19. GRB 250706C: Konus-Wind detection of a very bright GRB ~1200 s before GRB 250706B
  20. GRB 250704A: Swift/BAT-GUANO localization skymap of a burst
  21. GRB 250702F: GRANDMA observations
  22. GRB 250706A: Swift-XRT refined Analysis
  23. GRB 250706B: refined SVOM/MXT data analysis
  24. GRB 250706A: Swift/UVOT Upper Limits
  25. GRB 250706B: REM optical observations
  26. GRB 250706A: REM optical/NIR observations
  27. EP250706a/GRB 250706A: EP-WXT detection of a fast X-ray transient
  28. IceCube-250416A: DDOTI Optical Upper Limit
  29. IceCube-250706A: COLIBRÍ optical upper limits
  30. Swift GRB 250706A: Global MASTER-Net observations report
  31. GRB 250706A: JinShan optical upper limits
  32. EP250704A: NOWT Detection
  33. GRB 250706A: SVOM/C-GFT upper limit in eary phase
  34. The EP-WXT trigger 01709181580 is likely a flaring star
  35. GRB250706B: Swift-XRT counterpart detection
  36. GRB 250706B: iTelescope optical observations
  37. EP250704a / GRB 250704B: end of optical plateau phase and rapid fading of the counterpart
  38. GRB 250706B: SVOM/VT optical observation
  39. GRB 250706B: TRT bright optical counterpart detection
  40. GRB 250706A: GROWTH-India Telescope optical upper limit
  41. GRB 250706B: SVOM detection of a long burst
  42. GRB 250706A: Swift detection of a burst
  43. GRB 250704B: Swift-XRT refined Analysis
  44. GRBs 250702B,C,D,E / EP250702a: J band upper limit by SYSU 80cm infrared telescope
  45. EP250702a/GRB 250702B,C,D,E: Archival radio observations from ASKAP VAST
  46. GRB 250704B: Swift/UVOT Upper Limits
  47. GRB 250704A: Swift/UVOT Detection
  48. IPN triangulation of GRB 250703A
  49. EP250704a/GRB 250704B: GSP observations of the optical counterpart
  50. EP250704a/GRB 250704B: FTW optical and NIR observations of the counterpart
  51. EP250704a / GRB 250704B: NOT observations of the optical afterglow
  52. GRB 250702F: Kilonova-Catcher optical afterglow detection
  53. GRB250702F: afterglow detected by joint EP-ZTF shadowing program
  54. EP250704a / GRB 250704B: VLT/X-shooter spectroscopic redshift z = 0.661
  55. EP250704a / GRB 250704B: JinShan optical observations
  56. GRB 250704A: SVOM/VT optical observation
  57. EP250704a / GRB 250704B : GROWTH-India Telescope optical observations
  58. GRBs 250702B,D,E / EP250702a: fast fading, extremely red counterpart
  59. EP250704a / GRB 250704B: SVOM/VT optical blue counterpart
  60. EP250704a: refined analysis of the EP-WXT and FXT follow-up observations
  61. LIGO/Virgo/KAGRA S250704ab: Upper limits from Fermi-GBM Observations
  62. GRB 250704A: VLT/X-shooter afterglow discovery and spectroscopic redshift z = 1.091
  63. EP250704a / GRB250704B: Swift-XRT counterpart detection
  64. GRB 250704A: Swift-XRT afterglow detection
  65. EP250704a / GRB 250704B - REM observations
  66. GRB 250702F: GROWTH-India Telescope optical observations
  67. EP250704a / GRB 250704B: VLT/FORS2 optical afterglow detection
  68. GRB 250704A: REM retraction of optical afterglow detection and updated limit
  69. EP250702a: WFST optical observations
  70. EP250704a: COLIBRÍ optical counterpart candidate
  71. EP250704a: Einstein Probe detection of an X-ray transient
  72. GRB 250704B: SVOM/GRM observation of a short burst
  73. GRB 250702F: optical photometry from Konkoly
  74. GRB 250704A: REM detection of the optical afterglow
  75. LIGO/Virgo/KAGRA S250704ab: Coverage and upper limits from MAXI/GSC observations
  76. GRB 250702F: SVOM/VT optical observation
  77. GRB 250704A: SVOM detection of a burst
  78. GRB 250702F: Swift/UVOT Detection
  79. GRB 250702A: CALET Gamma-Ray Burst Monitor detection
  80. Fermi GBM Analysis of GRB 250702B (formerly B,D,E); dissociation of C burst
  81. Fermi GRB 250703A: Global MASTER-Net observations report
  82. GRBs 250702B,C,D,E / EP250702a: 2.2m CAHA optical upper limit
  83. GRB 250702F: Swift-XRT refined Analysis
  84. GRB 250702F: Fermi GBM Observation
  85. GRB 250702F: Leavitt Observatory optical observations
  86. GRB 250702F: AKO Optical Afterglow Detection
  87. GRBs 250702B,C,D,E / EP250702a: VLT/HAWK-I NIR candidate
  88. GRBs 250702B,C,D,E / EP250702a: SVOM/GRM observation
  89. GRB 250702A: GECAM-B detection
  90. GRB 250702F: Skynet Optical Observations
  91. GRB 250702B,C,D,E/EP250702a: COLIBRÍ optical upper limit
  92. EP250702a/GRB 250702B, C, D, E: EP-FXT follow-up observation
  93. GRB 250702F: TRT Optical Observation
  94. GRB 250703A: DDOTI Optical Upper Limit
  95. GRB 250702F: REM optical afterglow detection
  96. EP250702a: Global MASTER-Net observations report
  97. GRB 250702F: DDOTI Optical Observation
  98. GRB 250703A: Fermi GBM Final Real-time Localization
  99. EP250702a/GRB 250702B,C,D,E: GOTO optical upper limits
  100. GRB 250702F: COLIBRÍ Observations of the Afterglow

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