The long term perturbation of a Newtonian binary system by an incident gravitational wave is discussed in connection with the issue of gravitational ionization. The periodic orbits of the planar tidal equation are investigated and the conditions for their existence are presented. The possibility of ionization of a Keplerian orbit via gravitational radiation is discussed.

Zirconium oxide clusters are generated in the gas phase by laser ablation of the metal into a flow of ca. 5% O2/95% He at 100 psig and supersonic expansion into a vacuum chamber. Mass spectra of neutral gas phase zirconium oxide clusters are obtained through photoionization at three different laser wavelengths: 118, 193, and 355 nm. Ionization of the clusters with 118 nm laser radiation is thro...

Primordial stars are expected to be very massive and hot, producing copious amounts of hard ionizing radiation. The best place to study hard ionizing radiation in the local universe is in very metal-deficient Blue Compact Dwarf (BCD) galaxies. We have carried out a MMT spectroscopic search for [Ne v] λ3426 (ionization potential of 7.1 Ryd), [Fe v] λ4227 (ionization potential of 4 Ryd) and He ii...

The physical conditions which characterize individual Liners are obtained by fitting the observational spectra of the Ho et al. (1993) sample by model calculations. Composite models which consistently account both for shocks, accompanying the radial outward motion of the gaseous clouds, and a photoionizing radiation flux are used. Power-law or black body radiation is considered, depending on th...

Mass-analyzed threshold ionization (MATI) spectroscopy using synchrotron radiation (Advanced Light Source, Lawrence Berkeley National Laboratory) has been performed for Ar, N(2), O(2), N(2)O, H(2)O, C(2)H(2), and C(6)H(6). MATI allows for a better determination of ionization energies compared to those derived from photoionization efficiency curves traditionally used in synchrotron photoionizati...

An integrated Laser Ablation Fluid RAdiation simulation Code (LAFRAC) has been developed to estimate behaviors of highly energetic ions and neutral particles from laser produced plasmas, and to estimate ionization and recombination processes. Neutral particles cannot be controlled by electric and/or magnetic forces. Therefore, estimation of the number of neutral particles and mitigation of them...

Electron dynamics induced by resonant absorption of light is of fundamental importance in nature and has been the subject of countless studies in many scientific areas. Above the ionization threshold of atomic or molecular systems, the presence of discrete states leads to autoionization, which is an interference between two quantum paths: direct ionization and excitation of the discrete state c...

The results of the measurements of ionization due to the beta and gamma-radiations near the ground surface from 1967 through 1969 are reported, and are discussed comparing with those obtained from 1963 through 1966. The ionization due to the beta-radiation decreased gradu ally, and the mean value for this period is about I J at one meter above the ground surface, and that by the gamma-radiation...

Exposure of long duration to ionizing radiation causes a variety of neoplasms. The most common cases known to occur are malignant melanomas in skin, skin cancers, leukemias and breast carcinomas [1,2]. The Federal Aviation Administration (FAA) has recommended that aircrew members be exposed to no more than 20mSv per year for a 5 years average, with no more than 50mSv in a single year [3,4]. Rad...

introduction today, there is a growing interest in the use of hadrontherapy as an advanced radiotherapy technique. hadrontherapy is considered a promising tool for cancer treatment, given its high radiobiological effectiveness and high accuracy of dose deposition due to the physical properties of hadrons. however, new radiation modalities of dose delivery and on-line beam monitoring play crucia...