Document Type : Research Paper

Authors

• A A Abdulhasan
• Z A Dakhil

Department of Physics, College of Science, University of Baghdad, Iraq

Abstract

The electromagnetic properties of some even neutron rich Sulfur-isotopes ${ }^{32-42} \mathrm{~S}$ are studied through the electric quadrupole transition $\left(0_{1}^{+} \rightarrow 2_{1}^{+}\right)$. In particular, excitation energies $E_{x}$, occupancies, electric quadrupole moments $Q$, transition strengths $B(E 2)$, deformation parameters $\beta_{2}$ and the coulomb inelastic electron scattering form factors are calculated for the adopted isotopes within the framework of shell model. The shell model calculations are performed with full $s d$-model space, $p s d$ - and $s d p f$ - cross shell, using different interactions. The results are based on $s d b a$ and $p s d m k$ interactions for sulfur with $N \leq 20$, while sdpfk and $s d p f u$ interactions are dependent for sulfur with $N>20$. The core polarization effects $(C P)$ are included through the Boher-Mottelson $(B-M)$ and standard $(S T)$ effective charges to obtain a reasonable description of the electric quadrupole moments and C2 form factors. The results of $p s d m k$ and $s d b a$-interactions fail to reproduce the measured $B(E 2)$ strengths and deformation $\beta_{2}$ for ${ }^{32-36} \mathrm{~S}$, except for ${ }^{36} \mathrm{~S}$ nucleus is close to the measured value. The results for ${ }^{38-42} \mathrm{~S}$ with both $s d p f k$ and $s d p f u$ interactions nicely confirm the measured values of $B(E 2)$ strengths and deformation $\beta_{2}$ within the experimental error. The influence of the nuclear deformation parameter $\beta_{2}$ on the location of the diffraction minima of $\mathrm{C} 2$ form factors are also indicated.

Keywords

• Excited energy
• Quadrupole moments
• effective charges
• Deformation parameters
• Reduced transition probabilities
• Electron scattering form factor