Measurements of spin alignment of vector mesons and global polarization of hyperons with ALICE at the LHC

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We present the measurements related to global polarization of $\Lambda$ hyperons and spin alignment of $\mathrm{K^{*0}}~$ vector mesons at mid-rapidity for Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}~$= 2.76 TeV using the ALICE detector at the LHC.

• The global polarization measurements are carried out with respect to the first order event plane while the spin alignment measurements are carried out with respect to the production plane.
• No global polarization signal for $\Lambda$ is observed for 5-15\% and 15-50\% central Pb-Pb collisions.
• The spin density matrix element $\rho_{00}$ is found to have values slightly below 1/3 at low transverse momentum ($p_{\mathrm{T}}$) for $\mathrm{K^{*0}}~$ mesons, while it is consistent with 1/3 (no spin alignment) at higher $p_{\mathrm{T}}$.