  We present an update on the calculation of matrix elements of iso-vector
scalar, axial and tensor charges between a neutron and a proton state. These
matrix elements are needed to probe novel scalar and tensor interactions in
neutron beta-decay that can arise in extensions of the Standard Model at the
TeV scale. Our calculations are being done using valence clover fermions on
dynamical N_f=2+1+1 HISQ configurations generated by the MILC Collaboration. We
provide preliminary estimates of the dependence of these matrix elements on the
light quark masses, lattice spacing, and the time separation between the source
and sink of the nucleons. We also find that the renormalization constants
calculated using the RI-sMOM scheme are close to unity for the HYP smeared HISQ
lattices.
