Combined muon reconstruction at Level-2

An algorithm is presented which combines features extracted using stand-alone Level-2 algorithms in the muon system and the SCT, to produce a combined muon object at Level-2 for the region |eta|<1. Combination of the Level-2 stand-alone track and muon features is performed using fast, simple algorithms using linear extrapolations and analytic corrections. The resulting combined muon features enable substantial rejection of non-prompt muons from p and K decays, and a significant improvement in the pT resolution with which muons are measured. Level-2 trigger rates are calculated by convolving the extracted efficiencies of the algorithms applied with the expected cross-sections from various processes. The combined muon reconstruction algorithm is seen to gain a factor 3 reduction in the Level-2 rate from K and pi decays, relative to that output by the stand-alone Level-2 algorithms. The total rate output from the combined Level-2 muon reconstruction is seen to be ~2.5 kHz, for the region |eta|<1, for the 6 GeV low-pT threshold.