We present RBC/UKQCD's charm project using Nf=2+1 flavour ensembles with inverse lattice spacings in the range 1.73−2.77GeV and two physical pion mass ensembles. Domain wall fermions are used for the light as well as the charm quarks. We discuss our strategy for the extraction of the decay constants fD and fDs and their extrapolation to the continuum limit, physical pion masses and the physical heavy quark mass. Our preliminary results are fD=208.7(2.8)MeV and fDs=246.4(1.9)MeV where the quoted error is statistical only.
We outline our current approach to extend the reach in the heavy quark mass and present preliminary results.
