Baryon to Meson Ratios on the Near and Away-Side of Jets and their Centrality Dependence at STAR

摘要

We measure relative abundances of $K_{S}^{0}$, $\Lambda$ and $\bar{\Lambda}$in near-side and away-side cones correlated with triggered high-$p_{T}$particles in $^{197}$Au + $^{197}$Au collisions at $\sqrt{s_{NN}}$ = 200 GeV.The centrality dependence of identified particles in the triggered particlecones is also presented. Particle yields and ratios are extracted on thenear-side and away-side of the trigger particle. The associate-particle ratiosare studied as a function of the angle relative to the trigger particle azimuth$\Delta\phi$. Such studies should help elucidate the origin of themodifications in the jet like correlations observed in Au+Au collisionsrelative to p+p collisions. And these studies also will help understand thevariation of local parton densities at the away side. We discuss how thesemeasurements might be related to several scenarios for interactions of fastpartons with the medium created in Au+Au collision.