Quark Matter 2025

Hyperon polarization along the beam direction in pPb collision at CMS

Not scheduled

20m

Goethe University Frankfurt, Campus Westend, Theodor-W.-Adorno-Platz 1, 60629 Frankfurt am Main, Germany

Poster Chirality Poster session 2

Speaker

Chenyan Li (Shandong University (CN))

Description

The observation of hyperon polarization along beam direction ($P_z$) in nucleus-nucleus collisions has opened a new way to study the complex vortical structures of the QGP. With the high-statistics data collected by the CMS experiment, we present the first $P_z$ results for $\mathrm{\Lambda }$ and $\overline{\mathrm{\Lambda }}$ particles in pPb collision at $\sqrt{s_{NN}}=8.16$ TeV over a wide transverse momentum ($p_T$) and multiplicity range. The measured $P_z$ signal has been found to increase towards lower multiplicity and higher $p_T$. Comparison with theoretical calculations will be discussed. These results can shed light on the mechanism and theoretical implementation of spin polarization in heavy ion collisions.

Presentation materials

QM_poster_Chenyan.pdf