The (e, e 0 p) reaction was studied on targets of C, Fe, and Au at momentum transfers squared Q 2 of 0.6, 1.3, 1.8, and 3.3 GeV 2 in a region of kinematics dominated by quasifree electron-proton scattering. Missing energy and missing momentum distributions are reasonably well described by plane wave impulse approximation calculations with Q 2 and A dependent corrections that measure the attenuation of the final state protons. [S0031-9007 (98) The (e, e 0 p) reaction with nearly free electron-proton kinematics (quasifree) has proven to be a valuable tool to study the propagation of nucleons in the nuclear medium [1][2][3]. The relatively weak interaction of the electron with the nucleus allows the electrons to penetrate the nuclear interior and knock out protons. These studies complement nucleon-induced measurements of proton propagation in nuclei which give more emphasis to the nuclear surface. This paper reports the first results of a systematic study of the quasifree knockout of protons of 300-1800 MeV kinetic energy from carbon, iron, and gold targets. This energy range includes the minimum of the nucleon-nucleon (N-N) total cross section, the rapid rise in this cross section with energy above the pion production threshold, and extends to the long plateau in the energy dependence of the N-N total cross section. These features of the N-N interaction would be expected to be reflected in the energy dependence of attenuation of protons as they pass 5072 0031-9007͞98͞80(23)͞5072(5)$15.00

HoloLens by Microsoft Corp. is the world's first untethered Mixed Reality (MR) Head Mounted Display (HMD) system, released to developers in March 2016 as a Development Kit.We review in this paper the various display requirements and subsequent optical hardware choices we made for HoloLens. Its main achievements go along performance and comfort for the user: it is the first fully untethered MR headset, with the highest angular resolution and the industry's largest eyebox. It has the first inside-out global sensor fusion system including precise head tracking and 3D mapping all controlled by a fully custom onboard GPU. Based on such achievements, HoloLens came out as the most advanced MR system today. Additional features may be implemented in next generations MR headsets, leading to the ultimate experience for the user, and securing the upcoming fabulous AR/MR market predicted by most analysts.

The first measurements of the differential cross section for the d͑g, p͒n reaction up to 4.0 GeV were performed at the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson Laboratory. We report the cross sections at the proton center-of-mass angles of 36 ± , 52 ± , 69 ± , and 89 ± . These results are in reasonable agreement with previous measurements at lower energy. The 89 ± and 69 ± data show constituent-counting-rule behavior up to 4.0 GeV photon energy. The 52 ± and 36 ± data disagree with the counting-rule behavior. The quantum chromodynamics (QCD) model of nuclear reactions involving reduced amplitudes disagrees with the present data. To reconcile low energy and high energy descriptions of hadronic matter, nuclear physics must determine when it is justified to make a transition from meson-nucleon degrees of freedom to quark-gluon degrees of freedom in the description of a nuclear reaction. The QCD content of nuclei was studied first by Brodsky and Chertok [1]. A possible signature for this transition is that the reaction cross section begins to scale at some incident energy. If scaling were indeed observed, characterization of the approach to scaling would be essential to understand how the dynamics are simplified. High energy twobody photodisintegration of the deuteron ͑gd ! pn͒ is 4576 0031-9007͞98͞81(21)͞4576(4)$15.00

We report measurements of cross sections for the reaction 1 H(e,eЈK ϩ )Y , for both the ⌳ and ⌺ 0 hyperon states, at an invariant mass of Wϭ1.84 GeV and four-momentum transfers 0.5ϽQ 2 Ͻ2 (GeV/c) 2 . Data were taken for three values of virtual photon polarization ⑀, allowing the decomposition of the cross sections into longitudinal and transverse components. The ⌳ data are a revised analysis of prior work, whereas the ⌺ 0 results have not been previously reported.

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