90 likes | 163 Views
SSKT Study particle content around lepton+D M. Jones (Purdue), D. Usynin, J. Kroll (Penn). We expect that kaons are produced in association with B 0 s mesons We can’t measure the dilution of the same side kaon tag unless we see the B 0 s mix.
E N D
SSKT Studyparticle content around lepton+DM. Jones (Purdue), D. Usynin, J. Kroll (Penn) • We expect that kaons are produced in association with B0s mesons • We can’t measure the dilution of the same side kaon tag unless we see the B0s mix. • We might use a model to predict D (eg., Lund string fragmentation) • Can we find these kaons in the data? What are their properties?
Lepton-D Samples • Reconstruct lepton+D in jbmu0d/jbel0d. • Apply particle ID to tracks around the lepton+D candidates. • Compare l+D0/l+D+ with l+D+s • Do we find more kaons around l+D+s?
Particle ID • Apply “Diego” corrections to raw dE/dx • TOF reconstruction uses lepton and D decay tracks as constraints in t0 • Apply simultaneous fit to TOF+dE/dx in bins of pT or other variables. • Same approach as described in May 27 BPAK meeting. • Look at particles with R<0.7 with respect to lepton+D candidate
Momentum dependent fits • Example: K TOF p dE/dx K p
Particle content around l+D • Initial observations: • More pions per candidate for l+D0 and l+D+ than for l+D+s • Attributed to P-wave B meson decays • No obvious excess of kaons around l+D+s
Particle Content around l+D No significant difference
pLrel Dependence • Previous comparison was for all kaons • Select fragmentation candidates based on maximum pLrel Excess around the l+D+s
Comparison with toy MC • Pythia study shows similar behavior. • Do we have sensitivity to fragmentation parameters in the model?
Summary • Additional work: • Cross checks measuring particle fractions in pure samples • Cross talk between lepton+D samples • Sensitivity to fragmentation parameters in Monte Carlo • Related work: • Same approach can be applied to opposite side to try to find the kaons from B-decays.