Investigation of beam linear coupling

For the beam transport system in storage ring, linear coupling is mainly caused by skew quadrupole and longitudinal solenoid field. It leads to emittance exchange and beam envelope augment. By using betatron motion of single particle in the presence of skew quadrupole and longitudinal solenoid field, the effect of the beam linear coupling is preliminarily investigated. Beam emittance variation due to skew quadrupole is obtained too.