Speaker
Description
One of the fundamental goals of heavy-ion collision experiment is to map out the temperature $(T_{f})$ and baryon chemical potential $(\mu_{B}^f)$ of the Quantum Chromodynamics (QCD) phase diagram at which chemical freeze-out occurs - a point on the phase diagram when the chemical composition of the system is fixed. The cumulants of conserved quantities (net-charge, net-baryon number, net-strangeness) are directly related to the quark number susceptibilities calculated with lattice QCD. In a fluctuation analysis, net-pion, net-proton, and net-kaon are typically used as proxies for net-charge, net-baryon, and net-strangeness respectively. The $\Lambda$-particle consists of a strange quark and it is as well a baryon. Hence, measuring the cumulants of net-$\Lambda$ distributions provides insight into the fluctuations of net-strangeness and net-baryon number.
In addition, the ratios of net-$\Lambda$ cumulants that are used to estimate freeze-out parameters can be compared to the ones extracted using net-proton to identify the signature of a flavor hierarchy, that is, if heavier quarks may freezeout at a different $(T_{f})$ and $(\mu_{B}^f)$ from lighter quarks.
In this poster, we will present the measurement of the first and second order cumulants of net-$\Lambda$ distributions in Pb-Pb collisions at $\sqrt{s_{NN}}$= 5.02 TeV using the ALICE detector.
