Low lying nucleons from chirally improved fermions

There are two competing pictures for understanding baryon physics in different mass regions. For hadrons with heavy quarks linear confinement and perturbative gluon exchange corrections [1] provide a satisfactory description. For lighter quarks towards the chiral limit we have to expect manifestations of spontaneous chiral symmetry breaking [2]. Lattice studies can shed light on the relevant mechanisms. In particular after the advent of Ginsparg-Wilson fermions it is now also possible to run computations relatively close to the chiral limit. However, exact chiral fermion actions (like the overlap action) are very costly. On the other hand, recently developed approximate solutions of the Ginsparg-Wilson equation allow to work at relatively small quark masses at only moderate numerical cost. Two such approximate solutions, the parametrized fixed point action and the chirally improved action, have been studied in the BGR-collaboration [3,4]. Here we present results for low lying nucleon states computed with the chirally improved (CI) action [5]. The CI operator is a parameterization of the Dirac operator with terms essentially restricted to the hypercube. It allows for simulations at pseudoscalar-