Search NASA⌕ Search

Engineering topics

Reinhold, Joerg

Publications and source records attributed to Reinhold, Joerg.

Nuclear Physics Research at Jefferson Lab

The Florida International University (FIU) experimental nuclear physics group consists of four to five faculty, four to eight graduate students, at times one postdoctoral scholar, and several undergraduate students. Our research is mainly conducted at Jefferson Lab's Continuous Electron Accelerator Beam Facility. We are studying the electroprodcution of strangeness and also the interaction of strange baryons, hyperons, with nuclear matter; the effects of two-photon exchange on nuclear form factor measurements; the short range correlations in nuclei; and the production of exotic mesons. Over the entire period of this project, members of the group have been leading the data acquisition and analysis efforts as co-spokespersons of 12 Jefferson Lab experiments, as well as contributed to the efforts of the broader JLab user community. This has resulted in the publication of over 300 papers in peer reviewed journals and conference proceedings. Twelve students received their Ph.D. and four their M.S. based on analysis of data collected during this project.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Observation of the Λ ⁷He Hypernucleus by the (e, e'K⁺) Reaction

An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, He Λ ⁷, was observed for the first time with the (e, e'K⁺) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The He Λ ⁷ binding energy supplies the last missing information of the A=7, T=1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.

Nakamura, S. N.↗

Probing the High Momentum Component of the Deuteron at High Q{sup 2}

The {sup 2}H(e,e{sup '}p)n cross section at a momentum transfer of 3.5 (GeV/c){sup 2} was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle {theta}{sub nq} and to extract missing momentum distributions for fixed values of {theta}{sub nq} up to 0.55 GeV/c. In the region of 35 deg. {<=}{theta}{sub nq}{<=}45 deg. recent calculations, which predict that final-state interactions are small, agree reasonably well with the experimental data. Therefore, these experimental reduced cross sections provide direct access to the high momentum component of the deuteron momentum distribution in exclusive deuteron electrodisintegration.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

ΛN final state interaction in (e'K e + ) Jefferson Lab experiment E91-016

Jefferson Lab experiment E91-016 studied kaon electroproduction on hydrogen, deuterium and helium targets at a beam energy of 3.245 GeV and four-momentum transfer, Q 2 , ranging from 0.34 to 0.5 GeV 2 . Among a variety of other topics, part of this study was the investigation of the threshold region for signatures of final-state interaction between the electroproduced Λ-hyperon and spectator neutron. Compared to a purely quasi-free description, an excess yield was observed in the threshold region. This is compared to the predictions from three different hyperon-nucleon potentials. Though the data exhibit some sensitivity to the tested hyperon-nucleon potentials, further studies would require a more dedicated measurement with better resolution in the threshold region.

08 HYDROGEN↗