The polarisation conversion of a linear polarized electromagnetic wave incident onto a two-dimensional (2D) electron system at an angle θ is theoretically studied. We consider the 2D system located at the interface between two dielectric media with different dielectric constants. An external dc magnetic field is assumed to be directed along the normal to the 2D electron layer. In such a configu...

Introduction: The Monte Carlo simulation is used to enhance reliability in the experiments related to nuclear instruments. in addition, that is used to calculate the different components of the neutron and gamma ray fluxes in boron neutron capture therapy(BNCT) and neutron capture (NCT)applications. BNCT is one of the methods in radiotherapy, that is used the neutron beam for ki...

beryllium chemical combination has a considerable effect on the design and fabrication of the241am9be neutron source. in this investigation the beryllium combinations were studied as a generator ofneutrons with various mass percentage, and the neutron yields were also calculated using the results of thealice and srim codes calculations per unit incident charge. the neutron yields of beryllium ...

Background: In high-intensity, mixed and pulsed neutron fields the use of spectrometers or area monitors with active detectors is useless in these conditions neutron measuring devices must have a passive detector. Here a passive neutron area monitor with CR39 track detector was designed and the response was calculated. Materials and Methods: The response of a passive neutron area monitor with C...

background: prompt gamma neutron activation analysis (pgnaa) is known as a non-invasive technique capable of measuring elemental concentration in voluminous samples in a short period of time. also it is a valuable diagnostic tool for total body elemental measurements. 252cf and 241am-be sources which are usually used in this method, generate not only neutrons, but also emit high-energy and unwa...

background: one of the main causes of induction of secondary cancer in radiation therapy is neutron contamination received by patients during treatment. objective: in the present study the impact of wedge and block on neutron contamination production is investigated. the evaluations are conducted for a 15 mv siemens primus linear accelerator.  methods: simulations were performed using mcnpx mon...

An air-core holey fibre design that supports a single-polarisation circularly symmetric mode is presented. The mechanism that isolates the single polarisation, the advantages of the design and fabrication efforts to date will be discussed.

Context. The Hinode mission has revealed copious amounts of horizontal flux covering the quiet Sun. Local dynamo action has been proposed to explain the presence of this flux. Aims. We sought to test whether the quiet Sun flux detected by Hinode is due to a local or the global dynamo by studying long-term variations in the polarisation signals detectable at the disc centre of the quiet Sun betw...

We present new medium-resolution spectropolarimetric observations of HD 45677 in the B and R-bands. A change in polarisation is detected across Hα, Hβ and Hγ confirming that the ionised region around the star is aspherical. (Q,U) points associated with these emission lines occur away from the continuum, defining a polarisation vector which points in the same direction for each of the lines at a...