STAR physics program and technical challenges with the RHIC energy scan with Au plus Au collisions

The future STAR physics program includes an Au + Au energy scan extending to low v root(S)NN. Among other things, this energy scan will provide a unique opportunity to search for the phase boundary between quark-gluon plasma (QGP) and hadronic gas (HG), and a key landmark, a possible critical point, in the QCD phase diagram. Due to its large uniform acceptance and ( with the addition of the time-of-flight detector) excellent particle identification capabilities, by the time of Run 10 ( in 2010) STAR will be uniquely positioned to cover this physics in unprecedented depth and detail, as well as other novel physics possibilities. Running at very low energies poses major new challenges for accelerator experts at RHIC and for physicists preparing for data taking. We report on the status of STAR preparation for Run 10.