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Nikolai V Mokhov

Publications and source records attributed to Nikolai V Mokhov.

2 recordsLinked to original sources

MCNP5 for proton radiography.

The developmental version of MCNP5 has recently been extended to provide for continuous-energy transport of high-energy protons. This enhancement involves the incorporation of several significant new physics models into the code. Multiple Coulomb scattering is treated with an advanced model that takes account of projectile and nuclear target form factors. In the next version, this model will provide a coupled sampling of both angular deflection and collisional energy loss, including straggling. The proton elastic scattering model is also new, based on recent theoretical work. Charged particle transport in the presence of magnetic fields is accomplished either by using transfer maps from the COSY INFINITY code (in void regions) or by using an algorithm adapted from the MARS code (in void regions or in scattering materials). Work is underway to validate and implement the latest versions of the Cascade-Exciton Model and the Los Alamos Quark-Gluon String Model, which will process inelastic nuclear interactions and generate secondary particles.

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Assessment of the prompt radiation hazards of trapped antiprotons.

Investigators at several laboratories are seriously considering the storage and transport, perhaps over long distances, of very low energy antiprotons as a part of basic physics research programs and perhaps even for practical applications. To do this will require proper attention to the prompt radiation hazards due to the release of energy in the annihilations of antiprotons with nuclei, under either planned or accidental circumstances. In this paper, the potential storage of very low energy antiprotons is discussed, and the major features of the radiation fields produced by their annihilations are reviewed both qualitatively and quantitatively. Detailed Monte Carlo shielding calculations for a conceptual source of annihilating antiprotons nearly at rest are presented. It is concluded that these radiation fields are readily understood and that the radiation hazards can be mitigated using conventional means.

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