  Recent experimental results obtained in STAR experiment at the Relativistic
heavy-ion collider (RHIC) with ion beams will be discussed. Investigations of
different nuclear collisions in some recent years focus on two main tasks,
namely, detail study of quark-gluon matter properties and exploration of the
quantum chromodynamics (QCD) phase diagram. Results at top RHIC energy show
clearly the collective behavior of heavy quarks in nucleus-nucleus
interactions. Jet and heavy hadron measurements lead to new constraints for
energy loss models for various flavors. Heavy-ion collisions are unique tool
for the study of topological properties of theory as well as the
magneto-hydrodynamics of strongly interacting matter. Experimental results
obtained for discrete QCD symmetries at finite temperatures confirm indirectly
the topologically non-trivial structure of QCD vacuum. Finite global vorticity
observed in non-central Au+Au collisions can be considered as important
signature for presence of various chiral effects in sQGP. Most results obtained
during stage I of the RHIC beam energy scan (BES) program show smooth behavior
vs initial energy. However certain results suggest the transition in the domain
of dominance of hadronic degrees of freedom at center-of-mass energies between
10--20 GeV. The stage II of the BES at RHIC will occur in 2019--2020 and will
explore with precision measurements in the domain of the QCD phase diagram with
high baryon densities. Future developments and more precise studies of features
of QCD phase diagram in the framework of stage II of RHIC BES will be briefly
discussed.
