Luescher-Weisz algorithm for excited states of the QCD flux-tube

Abstract

We present a version of the Luescher-Weisz multilevel algorithm ideally suited for studying excited states of the QCD flux tube. While the original version achieved error reduction only in the temporal direction, the new algorithm reduces fluctuations in the sources as well. We report on the implementation of this algorithm as well as improvement over the older method. We also present first results, where we see a good agreement with theoretical predictions from bosonic string models.