  The nearest two years on experiment STAR the upgrade is planned, which will
make it possible to identify particles up to momentum $\sim$ 3 GeV/c. This will
open possibility to carry out new and more detailed researches of properties of
a nuclear matter formed in nucleus-nucleus collisions at RHIC. In this work we
offer to carry out of the polarization studies, which can give important
additional information about the process of forming the new state of nuclear
matter, and also about properties of the formed state. A unique probe of
information about all stages of formation and evolution of nuclear matter are
dileptons, due to their electromagnetic interaction with the nuclear matter. In
this work we pay main attention to the examination of polarization
characteristics of dileptons.
