1. Work SummaryNSF Report, 16 Nov 2007 - 1 Patrick Ryan, MSU Summary of Work Single Top Single Top trigger Have determined the optimum lepton triggers (mu20i, e25i OR e60) Will study combinations of lepton triggers with jet and E T Miss triggers Single Top with early data Lower p T cut on the second jet ordered in p T improves singal Confirmed that kinematic distributions are acceptable Maintain code for MSU analysis package Level 2 Muon Trigger Determined parameters for combined  reconstruction in endcap Will share an organizing role with Alessandro DiMattia

2. Work SummaryNSF Report, 16 Nov 2007 - 2 Patrick Ryan, MSU Truth Efficiency Truth MC sample No event selection mu6 to mu20: 20% decrease ttbar (blue) slightly higher Reconstructed Efficiency Reconstructed MC sample Single Top event selection mu6 to mu20: 10% decrease All channels similar Single Top Triggers Muon Efficiency Offline cut p T > 20 GeV Reconstructed Efficiencies Truth Efficiencies mu20 mu6 Muon Triggers greater than 80% efficient

3. Work SummaryNSF Report, 16 Nov 2007 - 3 Patrick Ryan, MSU Reconstructed MC events mu6 Turn-on Turn-on behavior below 10 GeV Wt channel has higher efficiency mu20 Turn-on Between 10 and 25 GeV Channels similar at low p T Wt higher at high p T Single Top Triggers Muon Turn-on Use mu20 in single top selection mu6 mu20

4. Work SummaryNSF Report, 16 Nov 2007 - 4 Patrick Ryan, MSU Single Top Triggers Electron Efficiency Truth Efficiency Truth MC sample No event selection e25i to e60: 15% decrease All channels similar Reconstructed Efficiency Reconstruted MC sample Single Top event selection e25i to e60: 60% decrease Channels differ at e60 t and s-channel: 22% eff Wt and ttbar 40% eff Reconstructed Efficiency Truth Efficiency Offline cut p T > 25 GeV e25i e60 e25i greater than 90% efficient

5. Work SummaryNSF Report, 16 Nov 2007 - 5 Patrick Ryan, MSU Single Top Triggers Electron Turn-on Curve Reconstructed MC events e25i Turn-on Between 10 and 25 GeV Channels similar at low p T Channels differ at high p T e60 Turn-on Between 10 and 60 GeV Channels differ at low p T Wt (black) & ttbar (purple) differ from s-channel (red) & t-channel (blue) Curves cross at 60 GeV e60 has no isolation cut e25i OR e60 About 3% efficiency gain Includes “tails” of top Use e25i OR e60 in single top selection e25i e60