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Orbital and Spin Magnetic Dipole Strength in a shell model calculation with $ΔN$=$2$ excitations: $^8\mbox{Be}$

M. S. Fayache·L. Zamick
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Abstract

The magnetic dipole strength and energy-weighted strength distribution is calculated in $^8\mbox{Be}$, as well as the separate orbit and spin parts. All $ΔN$=$2$ excitations over and above (and including) the configuration $0s^4$$0p^4$ are included. The interaction has a central, two-body spin-orbit and a tensor part. The energy- independent and energy-weighted {\underline orbital} strength distribution is remarkably insensitive to the presence or absence of the spin-orbit or tensor interaction -not so the spin strength. The energy-weighted strength distribution can be divided into a low enegy and a high energy part. The high energy orbital part is somewhat less but close to the low energy part, in fair agreement with a prediction that they be equal by de Guerra and Zamick and by Nojarov. There is a wide plateau separating the low energy part from the high energy part.

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M. S. Fayache, L. Zamick. 1994-06-07. Orbital and Spin Magnetic Dipole Strength in a shell model calculation with $ΔN$=$2$ excitations: $^8\mbox{Be}$. https://doi.org/10.1016/0370-2693(94)90795-1

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