Semileptonic Decays D exp(+) -> eta exp(') l exp(+) v With Generic Reconstruction Of Fully Hadronic D exp(+) And D exp(0) Decays
Gray, Richard Carl
We study the semileptonic decays D exp(+) -> n exp(')e exp(+)v and D exp(+) -> ne exp(+)v using 818 pb exp(-1) of e exp(+) e exp(-) collisions recorded by the CLEO-c detector located at the Cornell Electron Storage Ring. We employ a technique that uses the detector hermeticity to reconstruct the neutrino as missing energy and momentum. We improve the neutrino resolution by developing a generic algorithm to reconstruct the non-signal D, and constrain systematic uncertainties in the efficiency by using the algorithm to measure the branching fractions of D exp(+) and D exp(0) hadronic decays. We observe and measure the branching fractions of 67 hadronic decays, 32 of which are not listed in the PDG 2008. We find B(D exp(+) -> n exp(') e exp(+)v) = (2.16 +/- 0.53 +/- 0.05 +/- 0.05) x 10 exp(-4) and B(D exp(+) -> ne exp(+)v) = (11.7 +/- 0.98 +/- 0.34 +/- 0.26) x 10 exp(-4) . Among the 67 D hadronic branching fractions observed in this analysis, we discover the decay B(D exp(+) -> Pi exp(+)nn) = (0.34 +/- 0.06 +/- 0.032)% which is unexpectedly large considering the limited phase space available to the decay.
dissertation or thesis