Orateur
Description
The difference between the spin alignments of $K^\ast$ and those of $\phi$ at the low collisional energies is a puzzle raised by the recent experiments. Unlike $\phi$ meson, $K^*$, carrying a unit strange charge, should react to strange potential. In this talk, I shall first convince you that the strange chemical potential is not small in a brayon-rich medium for keeping strange neutrality, and then derive the spin alignment induced by strange, and hence baryon chemical potential gradient using linear response theory, with the transport coefficients expressed, w/o any approximation, in terms of the $K^*$'s in-medium spectral properties by employing Ward-Takahashi identity. The magnitudes of these coefficients, and hence of the spin alignment, will be further estimated under the quasi-particle approximation.
