10 research outputs found
The Photodissociation of and the Solar Neutrino Problem
The extraction of the photodissociation cross sections of from Coulomb
dissociation experiments is investigated. A careful study is done on the
contributions of the E1, E2 and M1 multipolarities to the breakup. A comparison
with the data of a recent experiment is performed. It is shown that the
extraction of the radiative capture cross sections which
are relevant for the solar neutrino problem is not affected appreciably by
Coulomb reacceleration. A non-perturbative model is used for the purpose.
Emphasis is put on the perspectives for future experiments which are planned at
the University of Notre Dame, RIKEN (Japan), and GSI (Germany). An analysis of
the total yields of ``photon-point" processes in inelastic electron scattering
is also done.Comment: 23 pages, plain Latex. 12 figures available upon request
Spin-Momentum Correlations in Quasi-Elastic Electron Scattering from Deuterium
We report on a measurement of spin-momentum correlations in quasi-elastic
scattering of longitudinally polarized electrons with an energy of 720 MeV from
vector-polarized deuterium. The spin correlation parameter was
measured for the reaction for missing
momenta up to 350 MeV/ at a four-momentum transfer squared of 0.21
(GeV/c). The data give detailed information about the spin structure of the
deuteron, and are in good agreement with the predictions of microscopic
calculations based on realistic nucleon-nucleon potentials and including
various spin-dependent reaction mechanism effects. The experiment demonstrates
in a most direct manner the effects of the D-state in the deuteron ground-state
wave function and shows the importance of isobar configurations for this
reaction.Comment: 4 pages, 3 figures, submitted to Phys. Rev. Lett. for publicatio
Investigation of the performance of thermally generated gold nanoislands for LSPR and SERS applications
Mixed valence effect of Se6+ and Zr4+ on structural, thermal, physical, and optical properties of B2O3–Bi2O3–SeO2–ZrO2 glasses
Annama H5 Meteorite Fall: Orbit, Trajectory, Recovery, Petrology, Noble Gases, and Cosmogenic Radionuclides
Smart Inorganic and Organic Pretreatment Coatings for the Inhibition of Corrosion on Metals/Alloys
High-Temperature Electronic Materials: Silicon Carbide and Diamond
The physical and chemical properties of wide-band-gap semiconductors make these materials an ideal wide bandgapsemiconductor choice for device fabrication for applications in many different areas, e.g. light emitters, high-temperature and high-power electronics, high-power microwave devices, micro-electromechanical system (MEM) technology, and substrates for semiconductor preparation. These semiconductors have micro-electromechanical system (MEMS) been recognized for several decades as being suitable for these applications, but until recently the low material quality has not allowed the fabrication of high-quality devices. In this material quality chapter, we review the wide-band-gap semiconductors, silicon carbide and diamond. Silicon carbide electronics is advancing from the research stage to commercial production. The commercial availability of single-crystal SiC substrates during the early 1990s gave rise to intense activity in the development of silicon carbide devices. The commercialization started with the release of blue light-emitting diode (LED). The recent release of high-power Schottky diodes was a further demonstration of the progress made towards defect-free SiC substrates. Diamond has superior physical and chemical properties. Silicon-carbide- and diamond-based diamondsilicon carbide (SiC) electronics are at different stages of development. The preparation of high-quality single-crystal substrates of wafer size has allowed recent significant progress in the fabrication of several types of devices, and the development has reached many important milestones. However, high-temperature studies are still scarce, and diamond-based electronics is still in its infancy