We report incoherent quasielastic neutron scattering experiments on the thermotropic liquid crystal 4-n-octyl-4'-cyanobiphenyl. The combination of time-of-flight and backscattering data allows analysis of the intermediate scattering function over about three decades of relaxation times. Translational diffusion and uniaxial molecular rotations are clearly identified as the major relaxation proce...

We investigate the effects of baryon/anti-baryon inhomogeneity on primordial nucleosynthesis. Recent work claims that electroweak baryogenesis could give rise to distinct regions of net baryon and anti-baryon number, which could survive until the nucleosynthesis epoch. We discuss neutron diffusion effects on nucleosynthesis yields in these models and speculate on the prospects for obtaining con...

We derive diffusive currents in strongly coupled Coulomb ion mixtures in dense stellar matter. Coulomb coupling in the presence of gravity and electric fields, induced by gravity owing to plasma polarization, creates a specific diffusion current which separates ions with the same A/Z (mass to charge number ratios) but different Z. This Coulomb separation can be important in white dwarfs and neu...

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...

We extend our initial study of diffusive nuclear burning (DNB) for neutron stars (NSs) with Hydrogen atmospheres and an underlying layer of proton capturing nuclei. Our initial study showed that DNB can alter the photospheric abundance of Hydrogen on surprisingly short timescales (102−4 yrs). Significant composition evolution impacts the radiated thermal spectrum from the NS as well as its over...

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...

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...