arXiv subjects

M. S. Fayache

Publications and source records attributed to M. S. Fayache.

21 records · Page 2Linked to original sources

arXiv1994

A Limited Symmetry Found by Comparing Calculated Magnetic Dipole Spin and Orbital Strengths in $^4\mbox{He}$

Allowing for $2$$\hbar ω$ admixtures in $^4\mbox{He}$ we find that the summed magnetic dipole isovector orbital and spin strengths are equal. This indicates a symmetry which is associated with interchanging the labels of the spin with those of the orbit. Where higher admixtures are included, the orbital sum becomes larger than the spin sum, but the sums over the low energy region are still nearly the same.

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arXiv1994

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

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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arXiv1994

Resistance to Collapse: The Tensor Interaction

We consider negative-parity excitations in $^4\mbox{He}$, $J^π$=$0^-$ and $1^-$ with isospin $T$=$0$ and $T$=$1$. We show tha t, in contrast to one-particle one-hole results, in a shell model diagonalization none of the above collapses to zero energy as the strength of the tensor interaction is increased.

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