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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"

28260 results found.

  1. Fermi GRB 260130A: Global MASTER-Net observations report
  2. Fermi GRB 260129A: Global MASTER-Net observations report
  3. GRB 260128B: LCO optical upper limits
  4. GRB 260128B: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  5. EP260128a: J band upper limit by SYSU 80cm infrared telescope
  6. GRB 260127A: Swift-BAT refined analysis
  7. GRB 260127B: Swift-XRT observations
  8. GRB 260127A: INASAN-Kislovodsk, SAO RAS, and Terskol K-800 optical observations
  9. GRB 260128A / EP260128a: Fermi-GBM Sub-Threshold Detection
  10. EP260128a: NOT optical counterpart candidate
  11. EP260128a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  12. EP260128a: Liverpool Telescope optical observations and possible counterpart
  13. EP260128a: LCO optical upper limits
  14. EP260128a: Global MASTER-Net observations report
  15. EP260128a: Einstein Probe detection of an X-ray transient
  16. Fermi GRB 260127A: Global MASTER-Net observations report
  17. GRB 260127A: Fermi GBM Observation
  18. IceCube-260125A: Upper limits from a search for additional neutrino events in IceCube
  19. GRB 260127A: COLIBRÍ optical observations
  20. EP260126a: Seimei/TriCCS optical upper limit
  21. GRB 260127A : MITSuME Akeno optical afterglow candidate detection
  22. GRB 260127A: Swift-XRT refined Analysis
  23. GRB 260127A: SVOM/C-GFT optical observations
  24. GRB 260127A: Enhanced Swift-XRT position
  25. Fermi GRB 260127B: Global MASTER-Net observations report
  26. Swift GRB 260127A: Global MASTER-Net observations report
  27. GRB 260127A: LCO optical afterglow discovery
  28. GRB 260127A: Swift detection of a burst
  29. GRB 260125A: Swift-XRT observations
  30. EP260126a: Optical upper limit with Kinder observations
  31. EP260126a: Liverpool Telescope optical upper limits
  32. EP260126a: Further NOT optical upper limits
  33. EP260126a: COLIBRÍ optical upper limits
  34. EP260126a: NOT optical observations
  35. EP260126a: Einstein Probe detection of a fast X-ray transient
  36. Fermi-LAT Gamma-ray Observations of IceCube-260125A
  37. GRB 251222A: SVOM/ECLAIRs refined analysis
  38. GRB 260125A: GOTO candidate optical counterpart
  39. Fermi GRB 260125B: Global MASTER-Net observations report
  40. GRB 260114A: SVOM/VT optical upper limits
  41. GRB 260122B: Swift-BAT refined analysis
  42. GRB 260120B: SVOM/GRM observation
  43. Swift GRB260122.97: Global MASTER-Net observations report
  44. EP260119a: Assy AZT-20 optical observations
  45. EP260119a: Mondy and SAO RAS optical upper limits
  46. EP260119a: Xinglong optical upper limit
  47. Fermi GRB 260120C: Global MASTER-Net observations report
  48. GRB 260120B: Swift-BAT refined analysis
  49. GRB 260120B: Swift-XRT refined Analysis
  50. EP260116a: COLIBRÍ further observations
  51. GRB 251122A / EP251122a: VLT/X-shooter host redshift z = 1.765
  52. GRB 260120B: Fermi GBM Observation
  53. EP260105a: GTC/HiPERCAM optical observations
  54. GRB 260120B: Swift/UVOT Detection
  55. GRB 260120B: COLIBRÍ optical upper limits
  56. SVOM GRB260121.06: Global MASTER-Net observations report
  57. GRB 260120B: Enhanced Swift-XRT position
  58. GRB 260120B: SVOM/C-GFT optical counterpart detection
  59. GRB 260101A: 239Alferov CubeSat detection
  60. EP260116a: COLIBRÍ observations of a tentative optical rebrightening
  61. GRB 260120B: Swift detection of a burst
  62. Swift GRB260120B: Global MASTER-Net observations report
  63. EP260119A: Mondy I-Band Observations
  64. Fermi trigger No 790601190: Global MASTER-Net observations report
  65. Fermi trigger No 790570272: Global MASTER-Net observations report
  66. GRB 260114A: Swift/UVOT Upper Limits
  67. EP260119a: Liverpool Telescope optical follow-up observations
  68. GRB 251202A: further radio observations with the VLA
  69. EP260119a: KAIT optical observations
  70. EP260119a: SVOM/VT optical observation
  71. EP260119a: NOT optical observations
  72. EP260119a: SAO RAS optical observations
  73. SVOM GRB260119.92: Global MASTER-Net observations report
  74. SVOM GRB260119.92: Global MASTER-Net observations report
  75. SVOM GRB260119.90: Global MASTER-Net observations report
  76. EP260116a: COLIBRÍ detection of a fading optical source
  77. GRB 260117A: Swift-XRT afterglow detection
  78. EP260119a: COLIBRÍ photometric redshift z ≈ 5.6
  79. EP260119a: Global MASTER-Net observations report
  80. EP260119a: LCO optical observations
  81. GRB 260117A: ZTSh optical upper limit
  82. EP260119a: COLIBRÍ optical counterpart candidate
  83. EP260119a: EP-WXT detection of a fast X-ray transient
  84. Swift GRB260118.48: Global MASTER-Net observations report
  85. GRB 260117A: SVOM/COLIBRÍ (FM-GFT) optical observations
  86. SVOM GRB260117.82: Global MASTER-Net observations report
  87. Fermi-LAT Gamma-ray Observations of IceCube-260115A
  88. Swift trigger on the HMXB 1A 1118-61
  89. GRB 260117A: SVOM/VT optical candidate
  90. GRB 260117A: SVOM/C-GFT upper limit
  91. GRB 260117A: Swift-XRT observations
  92. GRB 260117A: SVOM detection of a long faint burst
  93. EP 260116a: COLIBRÍ optical upper limit
  94. Swift triggered on the HMXB 1A 1118-61
  95. FRB 20251229A: COLIBRÍ further inspection of the updated localization
  96. EP260116a: Liverpool Telescope upper limits
  97. FRB 20251229A: Updated CHIME/FRB Baseband Localization of FRB 20251229A
  98. EP260116A: 1.3m DFOT optical upper limit
  99. GRB 260114A: VLT/MUSE spectroscopic observations
  100. IceCube-260115A: Upper limits from a search for additional neutrino events in IceCube

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