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arXiv · 2101.04820

Unexpectedly enhanced $α$-particle preformation in $^{48}$Ti probed by the $(p,pα)$ reaction

Yasutaka Taniguchi·Kazuki Yoshida·Yohei Chiba·Yoshiko Kanada-En'yo·Masaaki Kimura·Kazuyuki Ogata
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Abstract

The formation of $α$ particle on nuclear surface has been a fundamental problem since the early age of nuclear physics. It strongly affects the $α$ decay lifetime of heavy and superheavy elements, level scheme of light nuclei, and the synthesis of the elements in stars. However, the $α$-particle formation in medium-mass nuclei has been poorly known despite its importance. Here, based on the $^{48}{\rm Ti}(p,pα)^{44}{\rm Ca}$ reaction analysis, we report that the $α$-particle formation in a medium-mass nucleus $^{48}{\rm Ti}$ is much stronger than that expected from a mean-field approximation, and the estimated average distance between $α$ particle and the residue is as large as 4.5 fm. This new result poses a challenge of describing four nucleon correlations by microscopic nuclear models.

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Yasutaka Taniguchi, Kazuki Yoshida, Yohei Chiba, Yoshiko Kanada-En'yo, Masaaki Kimura, Kazuyuki Ogata. 2021-01-13. Unexpectedly enhanced $α$-particle preformation in $^{48}$Ti probed by the $(p,pα)$ reaction. https://doi.org/10.1103/physrevc.103.l031305

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