Электронный каталог

Статья

Hayrapetyan, A.
Observation of *L Hyperon Local Polarization in p-Pb Collisions at *%s&sub(NN)=8.16 TeV / A.Hayrapetyan, S.Afanasiev, V.Alexakhin, D.Budkouski, I.Golutvin, I.Gorbunov, V.Karjavine, V.Korenkov, 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, Z.Tsamalaidze, [CMS Collab.]. – Text : electronic // Physical Review Letters. – 2025. – Vol. 135, No. 13. – P. 132301. – URL: https://doi.org/10.1103/6ywq-gm61. – Bibliogr.: 79.

The polarization of the Λ and Λ^- hyperons along the beam direction has been measured in proton-lead (𝑝-Pb) collisions at a center-of-mass energy per nucleon pair of 8.16 TeV. The data were obtained with the CMS detector at the LHC and correspond to an integrated luminosity of 186.0±6.5  nb&sup(−1). A significant azimuthal dependence of the hyperon polarization, characterized by the second-order Fourier sine coefficient 𝑃&sub(𝑧,s⁢2), is observed. The 𝑃&sub(𝑧,s⁢2) values decrease as a function of charged particle multiplicity, but increase with transverse momentum. A hydrodynamic model that describes the observed 𝑃&sub(𝑧,s⁢2) values in nucleus-nucleus collisions by introducing vorticity effects does not reproduce either the sign or the magnitude of the 𝑝-Pb results. These observations pose a challenge to the current theoretical implementation of spin polarization in heavy ion collisions and offer new insights into the origin of spin polarization in hadronic collisions at LHC energies.



ОИЯИ = ОИЯИ (JINR)2025
Спец.(статьи,препринты) = С 343 в - Взаимодействие протонов с ядрами (Z>2). Изобарно- аналоговые состояния