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arXiv · 2108.07360

Structure of $^{43}$P and $^{42}$Si in a two-level shape-coexistence model

A. O. Macchiavelli·H. L. Crawford·C. M. Campbell·R. M. Clark·M. Cromaz·P. Fallon·I. Y. Lee·A. Gade·A. Poves·E. Rice
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Abstract

Exclusive cross sections for the $^{43}$P$(-1p)^{42}$Si reaction to the lowest $0^+$ and $2^+$ states, measured at NSCL with GRETINA and the S800, are interpreted in terms of a two-level mixing (collective) model of oblate and prolate co-existing shapes. Using the formalism developed for deformed nuclei we calculate the spectroscopic amplitudes and exclusive cross-sections in the strong coupling limit, where for $^{43}$P the schematic wavefunction includes the coupling of the Nilsson [211]$\frac{1}{2}$ proton orbit. Good agreement with the experimental data is obtained when the amplitude of the oblate configuration is $\gtrsim$ 80\%, suggesting that both nuclei are predominantly oblate, in line with theoretical expectations.

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A. O. Macchiavelli, H. L. Crawford, C. M. Campbell, R. M. Clark, M. Cromaz, P. Fallon, I. Y. Lee, A. Gade, A. Poves, E. Rice. 2021-08-16. Structure of $^{43}$P and $^{42}$Si in a two-level shape-coexistence model. https://doi.org/10.1103/physrevc.105.014309

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