  Beam collisions with a crossing angle at the interaction point have been
applied in high intensity colliders to reduce the effects of parasitic
collisions which induce emittance growth and beam lifetime deterioration. The
crossing angle causes the geometrical reduction of the luminosity. Crab cavity
can be one of the most promising ways to compensate the crossing angle and to
realize effective head-on collisions. Moreover, the crab crossing mitigates the
synchro-betatron resonances due to the crossing angle. Crab cavity experiment
in SPS is proposed for deciding on a full crab-cavity implementation in LHC. In
this paper, we investigate the effects of crab crossing on beam dynamics and
its life time with the global scheme.
