Performance of the LiF-TEA ring imaging Cherenkov detector at CLEO
We describe the particle identification capability of the CLEO RICH system. This system consists of a 1 cm thick LiF radiator coupled to a photon detector that uses wire proportional chambers filled with a mixture of CH4 and TEA. We discuss the yield of photoelectrons observed per ring and the angular resolution. We show the efficiencies achieved for particle identification and the associated fake rates from data collected with both CLEO III and CLEO-c detectors. Finally we show examples of the particle separation ability which is excellent for both CLEO III and CLEO-c data.
Evidence for $B^{(*)}_s$ Production at the ϒ(5S)
Based on data collected by the CLEO III detector at CESR, we started a series of investigations to open the mysteries of the ϒ(5S) resonance decay properties. Bs mesons are expected to decay predominantly into Ds meson, while the lighter B mesons decay into Ds only about 10% of the time. We exploit this difference to present the first evidence of a substantial production of Bs mesons at the ϒ(5S) resonance. We make here a preliminary model dependent estimate of the ratio of to the total quark pair production at the ϒ(5S) energy to be (21 ± 3 ± 9)%.
Microwave source with enhanced radiation power based on orbitron MASERs
We have proposed the design of high power microwave source in a vacuum tube based on the theory of negative mass instability. The proposed source does not operate based on a slow-wave structure but instead makes use of accelerated charged particles. In our structure, an electron emitter injects the charged particles into to the cavity. Emitted particles move around the anode, which leads to electron acceleration and emission of electromagnetic waves with a specific frequency. In this paper, we have enhanced the output power and frequency of microwave source by variation of particles initial energy and the number of anodes incorporating their specific arrangement and applied voltages. Working at room temperature, compactness, wide bandwidth, and tunability of output frequency are among the advantages of the proposed source.