We propose a new method to evaluate the Lellouch-Luscher factor which relates the $Delta I=3/2$ $Ktopipi$ matrix elements computed on a finite lattice to the physical (infinite-volume) decay amplitudes. The method relies on the use of partially twist
ed boundary conditions, which allow the s-wave $pipi$ phase shift to be computed as an almost continuous function of the centre-of-mass relative momentum and hence for its derivative to be evaluated. We successfully demonstrate the feasibility of the technique in an exploratory computation.
From simultaneous fits to the data from the 2+1 flavor DWF ensembles generated by the RBC and UKQCD collaborations at two different lattice spacings, we present preliminary continuum results for light hadrons. We focus on light pseudoscalar decay con
stants and quark masses. Several approaches to the calculation of the lattice spacing are discussed and the errors associated with the chiral extrapolation are explained. We make use of reweighting in the dynamical strange quark mass such that our ensembles have a self-consistently determined strange quark mass.
