The giant flares produced by highly magnetized neutron stars, "magnetars," are the brightest sources of high energy radiation outside our solar system. Serendipitous observations with NASA's Rossi X-ray Timing Explorer (RXTE) of the two most recent flares resulted in the discovery of high frequency oscillations in their X-ray fluxes. The frequencies of these oscillations range from = 20 Hz to a...

Introduction: Neutron contamination is very harmful for the patients receiving radiation therapy due to the high relative biological effect of neutrons. Medical linear accelerators head are made up of materials with high atomic numbers, and High-energy photons interaction with heavy materials can produce neutron contamination. In this study, neutron equivalent dose, neutron spe...

The recoil proton energy response has been measured by exposing cylindrical cells, filled with BC501A BICRON liquid scintillator, to mono-energetic neutron reference fields. We determine the required calibration parameters and report the detailed procedures for the experimental data handling. A dedicated Montecarlo simulation has successfully been used to check the consistency of the experiment...

Introduction: Environmental and occupational human exposure from neutron source can lead to the serious biologic effects. The aim of this study is to evaluate the cancer incidence risk for various human organs at different neutron dose levels due to exposure from an Americium-241/Beryllium (Am-241/Be), a standard neutron source for calibration purposes. Material and Methods: We measured ambient...

Neutron sources employed in different applications in both medicine and industry. Due to the harmful effects of neutron particles on living organisms, radiation shields have played a vital role in radiation protection against neutrons. In recent decade, numerous investigations conducted on the design and fabrication of nanocomposites as more efficient shielding materials against fast and therma...

background: a boron neutron capture therapy (bnct) facility, based on a dt neutron generator, with the final goal to find out a potential, alternative, solution to existing bnct treatment facilities which are based on nuclear reactors is examined. materials and methods: with the aim of the mcnp4b monte carlo code different beam-shaping assembly (bsa) configurations were considered. lead was sel...

in this research, cobalt and nickel sulfide nanoparticles (nps) were grown on almcm-41 matrix by using ion exchange method. the prepared samples were irradiated by thermalized neutron that emitted from am-be source up to fluencies (7.9+e9n/cm2). after that, x-ray diffraction (xrd), uv-vis spectroscopy, fourier transform infrared (ftir), scanning electron microscopy (sem) and transmission electr...

[1] Spacecraft observations in the inner heliosphere offer the first opportunity to measure 1–10 MeV solar neutrons. We discuss the cross sections for neutron production in solar flares and calculate the escaping neutron spectra for monoenergetic and power law particle spectra at the Sun and at the distance (0.48 AU) and observation angle of MESSENGER at the time of its reported detection of lo...