Quenched twisted mass QCD at small quark masses and in large volume

Abstract

As a test of quenched lattice twisted mass QCD, we compute the non-perturbatively O( a) improved pseudoscalar and vector meson masses and the pseudoscalar decay constant down to M PS/ M V = 0.467(13) at β = 6 in large volume. We check the absence of exceptional configurations and — by further data at β = 6.2 — the size of scaling violations. The CPU time cost for reaching a given accuracy is close to that with ordinary Wilson quarks at M PS/ M V ⋍ 0.6 and grows smoothly as M PS/ M V decreases.