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arXiv · 1307.3357

Study of Conduction Cooling Effects in Long Aspect Ratio Penning-Malmberg Micro-Traps

M. A. Khamehchi·C. J. Baker·M. H. Weber·K. G. Lynn
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Abstract

A first order perturbation with respect to velocity has been employed to find the frictional damping force imposed on a single moving charge due to a perturbative electric field, inside a long circular cylindrical trap. We find that the electric field provides a cooling effect, has a tensorial relationship with the velocity of the charge. A mathematical expression for the tensor field has been derived and numerically estimated. The corresponding drag forces for a charge moving close to the wall in a cylindrical geometry asymptotically approaches the results for a flat surface geometry calculated in the literature. Many particle conduction cooling power dissipation is formulated using the single particle analysis. Also the cooling rate for a weakly interacting ensemble is estimated. It is suggested that a pre-trap section with relatively high electrical resistivity can be employed to cool down low density ensembles of electrons/positrons before being injected into the trap. For a micro-trap with tens of thousands of micro-tubes, hundreds of thousands of particles can be cooled down in each cooling cycle. For example, tens of particles per micro-tube in a $5 cm$ long pre-trap section with the resistivity of $0.46 Ωm$ and the micro-tubes of radius $50 μm$ can be cooled down with the time constant of $106μs$.

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M. A. Khamehchi, C. J. Baker, M. H. Weber, K. G. Lynn. 2013-07-12. Study of Conduction Cooling Effects in Long Aspect Ratio Penning-Malmberg Micro-Traps. https://arxiv.org/abs/1307.3357

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