Laser post-ionization of sputtered molecules by pulsed Ga focused ion-beam (Ga-FIB) bombardment was examined for the detection and imaging of polycyclic aromatic hydrocarbons (PAHs) on particles. As model samples, pyrene and pelyrene adsorbed on TiO2, blended regents of pyrene and n-heneicosan were used. The TiO2 particle size was selected to be several micro-meters. Laser light and Ga-FIB were...

At room temperature, CO2 is transparent in the ultraviolet (UV) at wavelengths longer than 205 nm; however, at temperatures above 1000 K the CO2 absorption cross-section becomes significant in the region between 200 and 320 nm. Because CO2 is a major product of hydrocarbon combustion and because both the magnitude of the absorption cross-section and the shape of the UV absorption spectrum vary ...

Studies were designed to evaluate the effectiveness of pulsed modulated UV light waveforms for killing bacteria. Exposure of five strains of bacteria to the modulated information encoded in the light decreased the colony population from a confluent lawn to less than 20 colonies. However, approximately 2,000 colonies survived treatment with the same intensity and time of exposure to UV light lac...

The ability of ultraviolet resonance Raman spectroscopy (UVRRS) to determine structural, environmental, and analytical information concerning low-concentration aqueous biomolecules makes it a powerful bioanalytical and biophysical technique. Unfortunately, its utility has been limited by experimental requirements that preclude in situ or in vivo studies in most cases. We have developed the firs...

Electronic absorption, florescence excitation and AFM studies of selected homogeneous solutions and thin films of mesotetrakis (parahydroxyphenyl) porphyrin (THPP) (1), mesotetrakis (2, 3- dihydroxyphenyl) porphyrin 2, 3-OHPP) (2), mesotetrakis (3, 4-dihydroxyphenyl) porphyrin (3, 4-OHPP) (3) as well as Zn(II) derivative of 2, 3-OHPP (4) under UV lamp and green laser irradiation (532 nm) are ac...

We present measurements of superconducting tunnel junction (STJ) spectrometers optimized for extreme ultraviolet energies (EUV), between 20–200 eV. The high count rates demands of astronomical applications, such as solar flare studies, uniquely suit STJs as compared to other cryogenic spectrometers. We have simulated EUV measurements with the technique of multiphoton absorption using a pulsed U...

We report on the ablation and fabrication of optical waveguide using allyl-diglycol CR39 polymer. Pulse nanosecond (ns) laser (248 nm KrF) and continuous wave (CW) (244 nm argon-ion) irradiation are performed to observe surface modification on the polymer and potentially utilize it for channel waveguide. The pulsed UV laser creates craters with different depth as fluence increases to quantify t...

We present results from 200 hours of operation of an atmospheric super test beam system developed for the Pierre Auger Observatory. The approximate optical equivalence is that of a 100 EeV air shower. This new system combines a Raman backscatter LIDAR receiver with a calibrated pulsed UV laser system to generate a test beam in which the number of photons in the beam can be determined at ground ...