1. 1 Ratio mu+/mu- & muon reco studies on CRAFT data Status update, 6 Nov 2008 A.Calderon, INFN Padova & Ministerio de Educacion Y Ciencia, Spain F. Cavallo, INFN Bologna U.Gasparini, Universita’ di Padova & INFN Padova A.Gresele, INFN Padova & Univ. di Trento A.Meneguzzo, Universita’ di Padova & INFN Padova

2. 2 Intro statistics in CRAFT is not an issue: - Concentrate on variuos aspects of systematics: - perform different tracks selection, with loose/tight criteria on track topology/quality -study/keep control of momentum resolution, charge identification -Test stability of results against different runs, triggers, detector data quality… - Work on going… some examples on following slides…

3. 3 Example of DT-DQM certified good run DT local trigger efficiency good DT calibration, Run 67838 Missing DDU-trigger data in Wheel+1; data available anyway from trigger DCC

4. 4 “2 legs” STA muons Run 67838 5.3 M events analyzed (~ 15% of total triggers) DT segment multiplicity StandAlone muons associated hits to  tracks cut 1,7 M with N legs >1 difference in Z-impact parameter  z, both legs with N hit >30  z| < 20 cm 460,000 STA pairs  pT /pT~38% 1st leg 2nd leg

5. 5 STA muons 460,000 muon tracks Nhit>30 in both legs STA azimuth angle @ perigee 15,000 associated with Tracker track

6. 6 1 leg STA tracks vs Tracker tracks 1 leg STA Track, Nhit > 60 Tracker track  pT /pT~25%  pT /pT~22%  pT /pT~18%

7. 7 Mu+/mu- ratio: 1st look Using “one leg” STA Tracks with Nhit > 60 unphysical tail… 11,000 tracks (this corresponds to ~2% of total CRAFT statistics) uncorrected for charge mis-identification

8. 8 Stability: another run ( 66783 )