In recent years, a number of laser based H beam diagnostics systems have been developed in the Spallation Neutron Source (SNS). This talk reviews three types of laser based diagnostics at SNS: the laser wire profile monitors at superconducting linac (SCL), the laser transverse emittance scanner at high energy beam transport (HEBT), and the laser bunch shape monitor at medium energy beam transpo...

In this study, the impact of laser energy deposition on pressure oscillations and relative sound pressure levels (SPL) in an open supersonic cavity flow is investigated. Laser energy with a magnitude of 100 mJ is deposited on the flow just above the cavity leading edge and up to 7 dB of reduction is obtained in the SPL values along the cavity back wall. Additionally, proper orthogonal decomposi...

Two oppositely charged particles created within a microscopic space-time region can be separated, accelerated over a much larger distance, and brought to a recollision by a laser field. Consequently, new reactions become feasible, where the energy absorbed by the particles is efficiently released. By investigating the laser-dressed polarization operator, we identify a new contribution describin...

The interaction of a laser pulse with a Sn preplasma formed by a low energy prepulse was investigated for an extreme ultraviolet EUV lithography light source. A much lower ion kinetic energy and nearly the same conversion efficiency from laser to in-band 2% bandwidth 13.5 nm EUV light were simultaneously observed as compared with those from the direct interaction with a solid surface. The reaso...

We detect trace residues of RDX and TNT by surface photofragmentation fragment detection in real time at ambient conditions. An infrared or visible laser generates signature, NO molecular fragments, and a second, low energy, ultraviolet laser facilitates their detection by resonance enhanced multiphoton ionization. We present the effects of pump laser wavelength, laser energy, delay timing betw...

A novel scheme is presented for production of a thin (< 1 mm) uniform vapor layer over a large surface area (> 100 cm 2) by pulsed laser ablation of a solid surface. Instead of dispersing the laser energy uniformly over the surface, a modified Fabry-Perot interferometer is employed to concentrate the laser energy in very narrow closely-spaced concentric rings. This approach may be optimized to ...

introduction: : low level laser therapy (lllt) is gaining acceptance in clinical applications. for example, it is used as therapeutic modality in the repair of diabetic foot ulcer when conventional therapy was not effective, separately. the aim of this study is to determine the effect of local and travenous lllt for the healing of diabetic foot ulcer. methods:   this study contains 74 diabetic ...

introduction: since it is not possible to form an adequate micromechanical bond between resin cement and zirconia ceramics using common surface treatment techniques, laser pretreatment has been suggested for zirconia ceramic surfaces. the aim of this study was to evaluate the effect of carbon dioxide (co 2 ) laser treatment on shear bond strength (sbs) of resin cement to zirconia ceramic. metho...

The UCLA Neptune Laboratory CO2 laser system has been recently upgraded to produce 3ps multi-terawatt 10μm laser pulses. The laser energy is distributed over several 3ps pulses separated by 18ps. These temporally structured pulses are applied for laser driven ion acceleration in an H2 gas jet at a measured plasma density of 2x1019cm−3. Protons in excess of 20MeV have been observed in the forwar...

We present an ultra intense laser system with high repetition rate (300 Hz) and good stability (1% RMS shot to shot fluctuation). By focusing the 21fs laser beam down to a 1.6 μm spot with aberration-compensated optics, we demonstrated that a peak intensity of 4×10 W/cm was produced with 2.5 mJ pulse energy. The intensity was confirmed by laser field ionization of argon atoms. With 8 fs pulses,...