A prism grating using polymer stabilized liquid crystal was fabricated and its diffraction characteristics evaluated. Such a prism grating exhibits not only a periodic grating structure but also a prism-like gradient refractive index within each grating period. As a result, the diffraction behavior is asymmetric. The first order exhibits high diffraction efficiency while the zeroth order has a ...

A number of methods for producing sub-picosecond beam microbunching have been developed in recent years. A train of these bunches is capable of generating THz radiation via multiple mechanisms like transition, Cherenkov and undulator radiation. We utilize a bunch train with tunable spacing to selectively excite high order TM0,n modes in a multimode structure. In this paper we present experiment...

A technique for plroducing ultra-short electron bunches (e.g., 5100 fs) from a continuous electron beam using a short plasma wave section and a drift space is explored. The bunches are a fraction of a plasma wavelength long and are spaced by a plasma wavelength, making them of interest for iinjection into plasma accelerators or for driving a klystron-like structure to produce infrared radiation.

The high power multimode fiber-coupled laser sources, like solid state lasers or laser diodes as well as single mode and multimode fiber lasers, are now widely used in various industrial laser material processing technologies like metal or plastics welding, cladding, hardening, brazing, annealing. Performance of these technologies can be essentially improved by varying the irradiance profile of...

Research Board. The proposal consists of three main parts: 1) nucleon structure study via DrellYan process using a negative pion beam and transversely polarized proton target 2)nucleon structure study in exclusive positive and negative muon beam scattering off the unpolarized proton target 3)test of the chiral perturbative theory predictions via reactions of Primakoff scattering using hadron beam.

We investigated the space distribution of the rescattering electron wavepacket created in the laser-atom interaction by a full quantum simulation and a semiclassical calculation. Both the quantum simulation and the semiclassical calculation showed that the rescattering electron beam current intensity can reach the order of 10 A/cm, much intense than the conventional electron beam. Different fro...

The ability to autonomously assemble large structures in space is desirable for the construction of large orbiting solar arrays, interplanetary spacecraft, or space telescopes. One technique uses freeying satellites to manipulate and connect elements of the structure. Since these elements are often exible and lack embedded actuators and sensors, the assembly robot must use its own actuators and...

We consider the dynamics of the first vibrational mode of a suspension bridge, resulting from the coupling between its roadbed (elastic beam) and the hangers, supposed to be one-sided springs which respond only to stretching. The external forcing is due to time-periodic vortices produced by impinging wind on the bridge structure. We have studied some relevant dynamical phenomena in such a syste...

Kinetics and reaction mechanisms in polysomatic reactions of biopyriboles were reviewed in relation to mineralogical usage of HRTEM. HRTEM studies clarified the reaction mechanism and the polymerizing process from pyriboles to talc structure. Many zipper termination channels as reaction front were observed by tracing back from the obtained I-beam structure images. Another tunnel-like structures...

In this paper, by using an analogy among quantum mechanics, electromagnetic beam optics in optical fibers, and charge particle beam dynamics, we introduce the concept of coherent states for charged particle beams in the framework of the Thermal Wave Model (TWM). We give a physical meaning of the Gaussian-like coherent structures of charged particle distribution that are both naturally and artif...