objective: using megavoltage photons generated by medical linear accelerator is a common modality for the treatment of malignant. the crucial problem for using photon beams >8mv is the photoneutron yields that increase the risk of secondary cancer that treated with high-energy photon beams. the contaminated neutrons produced in different components of the accelerator head and rely on many param...

medical linear accelerators are one of the most widespread methods for cancer treatment. despite their advantages, unwanted photoneutrons are produced by high energy linacs. this photoneutrons are as undesired doses to patients and a significant problem for radiation protection of the staffs and patients. photoneutrons radiological risk must be evaluated because of their high let and range.in o...

One of the most important reactions of the URCA that lead to the cooling of a neutron star, is neutron beta-decay ( ). In this research, the energy spectra and wave functions of massive fermions taking into account the Anomalous Magnetic Moment (AMM) in the presence of a strong changed magnetic field are calculated. For this purpose, the Dirac-Pauli equation for charged and neutral fermions is ...

The hydrogenation of Li3N at low chemical potential has been studied in situ by time-of-flight powder neutron diffraction and the formation of a non-stoichiometric Li4-2xNH phase and Li4NH observed. The results are interpreted in terms of a model for the reaction pathway involving the production of Li4NH and Li2NH, which subsequently react together to form Li4-2xNH. Possible mechanisms for the ...

The low-temperature proton-ordered counterparts for ice-Ih, ice-III, ice-VI and ice-VII are investigated by first principle methods in conjunction with a graph enumeration technique. Two experimentally well calibrated disorder/order transitions, ice-Ih/ice-XI and ice-VII/ice-VIII, are used to validate the methodology we used herein and in both cases our approach is able to reproduce major exper...

It is well established that at ambient and supercooled conditions water can be described as a percolating network of H bonds. This work is aimed at identifying, by neutron diffraction experiments combined with computer simulations, a percolation line in supercritical water, where the extension of the H-bond network is in question. It is found that in real supercritical water liquidlike states a...

Much consideration has been given to the role of spin-orbit coupling (SOC) in 5d oxides, particularly on the formation of novel electronic states and manifested metal-insulator transitions (MITs). SOC plays a dominant role in 5d(5) iridates (Ir(4+)), undergoing MITs both concurrent (pyrochlores) and separated (perovskites) from the onset of magnetic order. However, the role of SOC for other 5d ...