  Within the framework of the generalized factorization in pQCD, we investigate
the multiple parton scattering and induced parton energy loss at twist-6 in
deeply inelastic e-A scattering with the helicity amplitude approximation. It
is shown that twist-6 processes will give rise to additional nuclear size
dependence of the parton energy loss due to LPM interference effect while its
contribution is power suppressed.
