The muon+track alley of the LHCb High Level Trigger

This note describes the LHCb Hlt1 Muon + Track alley, which is part of the High Level Trigger. This alley aims to provide high efficiency on B decays containing muons. It will be executed in events in which a L0 muon candidate with sufficient pT is found. The muon candidate is confirmed at the tracking stations and at the VELO and then tracks forming good vertices with the muon are searched for, being later confirmed in the tracking stations. In this note, the algorithm structure of the alley and the selection of discriminating variables are described. The performance on simulated semileptonic B decays is also shown