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Chaotic Scattering and Escape Times of Marginally Trapped Ultracold Neutrons



Kevin Coakley, J M. Doyle, S N. Dzhosyuk, L Yang, Paul R. Huffman


We compute classical trajectories of ultracold neutrons (UCNs) in a superconducting Ioffe-type magnetic trap using a symplectic integration method. We find that the computed escape time for a particular set of initial conditions (momentum and position) does not generally stabilize as the time step parameter is reduced unless the escape time is prompt (less than approximately 10 s). For energy intervals where more than half of the escape times computed for UCN realizations are numerically well determined, we predict the median escape time as a function of the midpoint of the interval.
Journal of Research (NIST JRES) -


chaotic scattering, escape time, Hamiltonian system, magnetic trap, symplectic integration, ultracold neutrons


Coakley, K. , Doyle, J. , Dzhosyuk, S. , Yang, L. and Huffman, P. (2005), Chaotic Scattering and Escape Times of Marginally Trapped Ultracold Neutrons, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed July 13, 2024)


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Created June 30, 2005, Updated October 12, 2021