Rubin-LSST

Abstract:

We report on a study of the invariant mass spectrum of the hadronic system in the decay τ^-→π^-π⁰ντ. This study was performed with data obtained with the CLEO II detector operating at the CESR e⁺e^- collider. We present fits to phenomenological models in which resonance parameters associated with the ρ(770) and ρ(1450) mesons are determined. The π^-π⁰ spectral function inferred from the invariant mass spectrum is compared with data on e⁺e^-π⁺π^- as a test of the conserved vector current theorem. We also discuss the implications of our data with regard to estimates of the hadronic contribution to the muon anomalous magnetic moment. ©2000 The American Physical Society.

Abstract:

We present a preliminary study of a new technique for measuring B⁰s mixing and CP violation using the decay B⁰s → J/ψφ, φ K⁺K^-, J/ψ → μ⁺μ^-. This technique utilizes the unequal lifetimes of the B⁰s CP even and odd eigenstates, and an angular variable decomposition of the CP content of the final state. This study is based on CDF Run-I observations and Run-II projections, and predicts that the B⁰s mixing parameter cursive Greek chis can be measured with high accuracy in untagged samples if this approach is adopted. A large CP asymmetry may also be possible to measure. The accuracy of this method is shown to increase for higher values of cursive Greek chis as the lifetime splitting of the CP eigenstates increases. The measurement of cursive Greek chis does not depend on tagging, whereas the observation of a CP-violating asymmetry does.