Carbon nanotubes (CNTs) are hardy and versatile, with remarkable material and electronic properties.udThey could be also useful in some extreme conditions as well, when using a CNT as a shotgun barrel toudshoot a beam of protons. The scheme nests two small hydrogen-rich fragments — which could be water ice,udparaffin, or some other low-Z material — within a larger CNT that has gold atoms chemically adsorbed inudits wall. The assembled structure is then zapped from the side with an ultraintense femtosecond laserudpulse. The laser partially ionizes the gold and fully ionizes the hydrogen and carbon in the assemblage.udAfter a few swings of the laser's electric field, significant numbers of electrons are blown off and form audcloud around the CNT. The now highly ionized coaxial structure generates a Coulomb potential in whichudthe protons from the nanotube accelerator are squeezed toward the axis and accelerated out both ends ofudthe CNT. The simulations indicate that even a non-optimized setup can produce highly collimated beamsudof nearly monoenergetic protons — 1.5 MeV for the parameters used. Such beams are of great interest inudfields as diverse as medicine, fusion energy, and materials engineering.When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35503
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