The thesis works that are presented in this Yearbook are very representative of the multi-disciplinary research activity performed within the context of the PhD educational and research program in Radiation Science and Technology (RST). The latter is specifically designed to provide the student with the state-of-the-art in a wide range of research fields related to the application of nuclear an...

Fields induced by a beam and penetrated outside the beam pipe can be used for a beam diagnostic. Wires placed in longitudinal slots in the outside wall of the beam pipe can work as a beam pickup. This has very small beam-coupling impedance and avoids complications of having a feed-through. The signal can be reasonably high at low frequencies. We calculate the beam-coupling impedance due to a lo...

Background: Intraoral radiographies are the most frequent X-ray examinations in humans. According to International Commission on Radiation Protection (ICRP) recommendations, the selection of a diagnostic reference level (DRL) should be specific to a country or region. Critica l organs such as thyroid gland are exposed to X-rays in intraoral radiography and these exposures should be kept as low ...

The dielectric susceptibility of a wide class of dielectric materials follows, over extended frequency ranges, a fractional power-law frequency dependence that is called the ‘universal’ response. The electromagnetic fields in such dielectric media are described by fractional differential equations with time derivatives of non-integer order. An exact solution of the fractional equations for a ma...

Two new cylindrically symmetric inhomogeneous string cosmological models are investigated in presence of magnetic field. We have assumed that F12 is the only non-vanishing component of electromagnetic field tensor Fij . The Maxwell’s equations show that F12 is the function of x alone whereas the magnetic permeability μ̄ is the function of x and t both. To get the deterministic solution, it has b...

BACKGROUND One goal of increasing awareness of radiation dose is to encourage personal and technical modifications in order to reduce the radiation exposure of patients and staff. OBJECTIVE To analyze the radiation doses incurred during diagnostic cerebral angiography and the angiographic techniques practiced over a 4-year period, in order to demonstrate the effectiveness of implementing radi...

It was successfully demonstrated at UVSOR-II that, by using an external laser source, various micro-density structures such as a femtosecond dip or periodic modulation could be created on an electron bunch circulating in a storage ring. The bunch with femtosecond dip emitted broadband coherent synchrotron radiation. That with periodic density modulation emitted coherent and monochromatic terahe...

A follow-up X-ray study was made of the west lobe of the radio galaxy Fornax A, (NGC 1316) based on new ASCA observations made in 1997 for 98 ks, and incorporating the previous observation in 1994 for 39 ks. The 0.7–10 keV spectrum of the emission can be described by a power-law of energy index 0.74 ± 0.10, which agrees with the synchrotron radio index of 0.9 ± 0.2. Therefore, the X-rays are re...

A plane-symmetric inhomogeneous cosmological model of perfect fluid distribution with electro-magnetic field is obtained. The source of the magnetic field is due to an electric current produced along the z-axis. F12 is the non-vanishing component of electromagnetic field tensor. To get a deterministic solution, we assume the free gravitational field is Petrov type-II non-degenerate. The behavio...

Computed near-field values of Poynting’s vector and electric and magnetic field intensities for a linear dipole are displayed in a way that aids visualization of the radiation process. The fields are computed for time-harmonic excitation, but are shown as a function of time to demonstrate the spatial ebb and flow of the fields around the dipole. By this means, the distinction between near and r...