Электронный каталог

Статья

Hayrapetyan, A.
Observation of Quantum Entanglement in Top Quark Pair Production in Proton-Proton Collisions at *%s=13 TeV / A.Hayrapetyan, S.Afanasiev, V.Alexakhin, D.Budkouski, I.Golutvin, I.Gorbunov, V.Karjavine, V.Korenkov, N.Krasnikov, A.Lanev, A.Malakhov, V.Matveev, V.Palichik, V.Perelygin, M.Savina, V.Shalaev, S.Shmatov, S.Shulha, V.Smirnov, O.Teryaev, N.Voytishin, B.S.Yuldashev, A.Zarubin, I.Zhizhin, A.Khvedelidze, Z.Tsamalaidze, [CMS Collab.] // Reports on Progress in Physics [Electronic resource]. – 2024. – Vol. 87, No. 11. – P. 117801. – URL: https://doi.org/10.1088/1361-6633/ad7e4d. – Bibliogr.: 117.

Entanglement is an intrinsic property of quantum mechanics and is predicted to be exhibited in the particles produced at the Large Hadron Collider. A measurement of the extent of entanglement in top quark-antiquark (tt^-) events produced in proton–proton collisions at a center-of-mass energy of 13 TeV is performed with the data recorded by the CMS experiment at the CERN LHC in 2016, and corresponding to an integrated luminosity of 36.3 fb*−*1 . The events are selected based on the presence of two leptons with opposite charges and high transverse momentum. An entanglement-sensitive observable D is derived from the top quark spin-dependent parts of the tt^- production density matrix and measured in the region of the t^-t production threshold. Values of D < −1/3 are evidence of entanglement and D is observed (expected) to be −0.480&sup(+0.026) &sub(−0.029) (−0.467&sup(+0.026)&sub( −0.029)) at the parton level. With an observed significance of 5.1 standard deviations with respect to the non-entangled hypothesis, this provides observation of quantum mechanical entanglement within tt^- pairs in this phase space. This measurement provides a new probe of quantum mechanics at the highest energies ever produced.



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 346.2в - Взаимодействие протонов с протонами
Спец.(статьи,препринты) = С 346.6д1 - Чармоний, боттомоний, топ-кварк. Очарованные частицы и др. резонансы из тяжелых кварков