Compensation of temperature drift in leaky-mode spectra for sensor applications

Leaky-mode spectroscopy enhanced with semitransparent metal films may be effectively used for optical gas detection. Most of the optical sensors show a large temperature drift which is detrimental for application purposes. In this paper a model for the compensation of a particular line shift in the leaky-mode spectrum is given and it is confirmed experimentally.     

Anomalous muon production in e+e− annihilations as evidence for heavy leptons

We have measured inclusive muon production in e⁺e^? annihilation for CMS energies between 3.6 and 5.0 GeV. Above 4 GeV the cross section cannot be explained by conventional sources like higher order QED processes or inclusive production of the $\text{J}\text{?}$ (3.1). It is, however, compatible with the pair production of heavy particles of a mass of about 1.9 GeV/c². Spin assignment and decay parameters are investigated.     

An investigation of the processes e+e−→μ+μ−γ and e+e−→e+e−γ

The reactions e⁺e^?→μ⁺μ^?γ and e⁺e^?→e⁺e^?γ have been studied with the CELLO detector at the PETRA storage ring. Data have been collected from $\text{s}\text{=14}\text{GeV up to}\text{46.8}\text{GeV}$. In a Dalitz plot analysis of the data, good agreement is found with QED, except for the region Mx_μγe>0.8 where the probability that QED describes the high energy data is at the percent level.     

Energy-energy correlations in e+e− annihilation into hadrons

Measurements of energy-energy correlations in hadronic final states produced in e⁺e^? annihilation at c.m. energies between 7.7 and 31.6 GeV are presented. The data are compared to perturbative QCD predictions. Good qualitative agreement above 20 GeV c.m. energy is found. The importance of non-perturbative effects is discussed, as well as the detailed behaviour of the correlation near 180°.     

Inclusive Jψ production in e+e− annihilation in the energy range from 4.0 to 5.0 GeV

We report on inclusive production of $\text{J}\text{ψ}$ (3.1)-mesons observed in e⁺e^?-annihilation in the energy range $\text{s}\text{= 4.0–5.0}\text{GeV}$. After substraction of the radiative tail of the ψ(3.7) direct production of the $\text{J}\text{ψ}$ (3.1) is found to be in the order of 0.1% of the total hadronic cross section. No enhancements are seen at $\text{s}\text{= 4.03}\text{GeV}$ and 4.4 GeV. The level is in agreement with expectations from violation of the Zweig-rule.