Introduction: GRID therapy is a treatment modality in which a high dose of radiation in a single fraction is given to the tumor. This technique previously was used to treat bulky tumors with orthovoltage beams. Recently, studies have been conducted to suggest that GRID therapy with megavoltage photons can be useful in palliative treatments. On the other hand, there has always ...

abstract background: with respect to the difference in the interaction of thermal neutron and x rays with matter, using two radiography systems of thermal neutron and x rays will yield highly valuable information for studying the inner structure of biologic samples. methods: the high sensitivity of thermal neutron to hydrogen, in particular, has led to recognizing this system as a useful tool i...

The possible effect of contrails in modifying the weather is reconsidered in the light of information obtained from ground-level contrails in Alaska. It appears likely that inadvertent cloud seeding b y jet aircraft may be of the same order of magnitude as that attained in commercial cloud seeding operations. Further investigation is needed; but in the meantime, the possibility of contrail cont...

Out-of-field doses from radiotherapy can cause harmful side effects or eventually lead to secondary cancers. Scattered doses outside the applicator field, neutron source strength values, and neutron dose equivalents have not been broadly investigated for high-energy electron beams. To better understand the extent of these exposures, we measured out-of-field dose characteristics of electron appl...

This paper summarizes three mathematical models used to describe how contaminant concentration profiles in soil may be inferred from the intensities of neutron-induced capture-gamma photon intensities measured at the soil surface. In particular, the linear regularization, linear regularization with an iterative positivity constraint, and the Backus-Gilbert methods are applied to the soil contam...

background: several landmine detection methods, based on nuclear techniques, have been suggested during the recent years. neutron energy moderation, neutron-induced gamma emission, neutron and gamma attenuation, and fast neutron backscattering are nuclear-based methods used for landmine detection. the aim of this study is to use backscattered neutron for landmine detection. materials and method...

A high-energy photon beam that is more than 10 MV can produce neutron contamination. Neutrons are generated by the [γ,n] reactions with a high-Z target material. The equivalent neutron dose and gamma dose from activation products have been estimated in a LINAC equipped with a 15-MV photon beam. A Monte Carlo simulation code was employed for neutron and photon dosimetry due to mixed beam. The ne...