Speaker
Zhenyu Chen
(Rice University (US))
Description
Observation of a long-range near-side two-particle correlation (known as the "Ridge") in high-multiplicity pp and pPb collisions opened up new opportunities of exploring novel QCD dynamics in small collision systems. To further investigate the origin of this phenomenon, studies of two-particle correlations with identified $K^0_s$ and Lambda trigger particles in 5.02 TeV pPb collisions are presented, and compared to PbPb collisions over a similar multiplicity range. The $K^0_s$ and Lambdas are cleanly reconstructed via their secondary decay vertices over a wide pseudorapidity and transverse momentum range. The second-order ($v_2$) and third-order ($v_3$) anisotropy harmonics of $K^0_s$ and Lambda are extracted from long-range correlations as a function of particle multiplicity and $p_T$. The wide $p_T$ coverage and rich sample of high multiplicity pPb events allow: (1) a precise examination of the mass ordering effect of $v_n$ at low $p_T$ as predicted by hydrodynamics for a collectively expanding medium; (2) exploration of possible constituent quark number scaling of $v_2$ and $v_3$ between mesons and baryons as was observed in high-energy nucleus-nucleus collisions.
Author
Zhenyu Chen
(Rice University (US))
Co-authors
Mr
Wei Li
(Rice University (US))
Zhoudunming Tu
(Rice University (US))
