Polarized $\phi$ meson rates with viscous corrections at RHIC

Abstract

We discuss the emission of $\phi$ mesons with longitudinal and transverse polarization in ultra-relativistic heavy ion collisions. In the hadronic phase and in leading order in the kaon diluteness, $\phi$ emission is isotropic and driven by the flavor singlet and octet vector spectral functions. At next to leading order, the emissivities receive a non-isotropic correction from the flavor octet spectral function, and the non-equilibrium contributions originating from the shear and bulk viscosities. Implications for the $\phi$ meson alignment in heavy-ion collisions are discussed.