C. Dukes

Measurement of J / psi, psi-prime and upsilon total cross-sections in 800-GeV/c p - Si interactions

Abstract We report on the analysis of Charmonium and Bottomium states produced in p-Si interactions at s =38.7 GeV . The data have been collected with the open geometry spectrometer of the E771 Experiment at the FNAL High Intensity Lab. J ψ , ψ′ and γ total cross sections as well as the ratio B(ψ′ → μμ)σ(ψ′) (B( J ψ → μμ)σ( J ψ )) have been measured. Results are compared with theoretical predictions and with results at other energies.

Charged kaon mass measurement using the Cherenkov effect

The two most recent and precise measurements of the charged kaon mass use X-rays from kaonic atoms and report uncertainties of 14 ppm and 22 ppm yet dier from each other by 122 ppm. We describe the possibility of an independent mass measurement using the measurement of Cherenkov light from a narrow-band beam of kaons, pions, and protons. This technique was demonstrated using data taken opportunistically by the Main Injector Particle Production experiment at Fermi National Accelerator Laboratory which recorded beams of protons, kaons, and pions ranging in momentum from +37 GeV/c to +63 GeV/c. The measured value is 491.3 1.7 MeV/c 2 , which is within 1.4 of the world average. An improvement of two orders of magnitude in precision would make this technique useful for resolving the ambiguity in the X-ray data and may be achievable in a dedicated experiment.

Electromagnetic and Hadron Calorimeters in the MIPP Experiment

The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons, and nucleons in π, K, and p interactions on various targets using beams from the Main Injector at Fermilab. The function of the calorimeters is to measure the production of forward-going neutrons and photons. The electromagnetic calorimeter consists of 10 lead plates interspersed with proportional chambers. It was followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. The data presented were collected with a variety of targets and beam momenta from 5 GeV/c to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons, and protons is discussed. The resolution for electrons was found to be 0.27 / E , and for hadrons the resolution was 0.554 / E with a constant term of 2.6%. The performance of the calorimeters was tested on a neutron sample.

The Fermilab E771 spectrometer: A large aperture spectrometer to study charm and beauty states as detected by decays into muons

This paper describes the final incarnation of the Fermilab High Intensity Lab spectrometer which operated for ten years in the Proton West Area of Fermilab in the execution of two experiments (E537 and E705) which studied hadroproduction of high mass dimuon pairs. The version of the spectrometer used in E771 differed from earlier versions of the spectrometer by the addition of a silicon microstrip detector, pad chambers and resistive plate counters. These additions were implemented to give the spectrometer the capability of detection of secondary decay vertices from B → μ or B → Jψ → μμ decays. As discussed, the spectrometer in a short data taking period was able to address many kinds of physics, other than beauty decays.

Search for CP violation in Ξ and A hyperon decays: Status of the HyperCP experiment

HyperCP (E871), a Fermilab experiment searching for CP violation in Ξ and A hyperon decays, finished its first data taking run at the end of 1997, and accumulated over one billion Ξ − and ¯Ξ + decays. A sensitivity of approximately 2×10 −4 in A ΞΛ (αΞαΛ - α¯Ξα¯Λ)/(αΞαΛ + α¯Ξα¯Λ) is expected. A non-zero value of A ΞΛ would be unambiguous evidence for direct CP violation. A brief review of CP violation in hyperon decays is given, the HyperCP spectrometer is described, and the status of the analysis and future prospects are discussed.