Investigation of $\alpha$ clustering with knockout reactions

Abstract

Our goal is to reveal how the $\alpha$ cluster amplitude is probed through $\alpha$ knockout reactions depending on reaction conditions, e.g., the incident energy. We consider ${}^{20}$Ne($p$,$p\alpha$)${}^{16}$O and ${}^{120}$Sn($p$,$p\alpha$)${}^{116}$Cd at 100-400 MeV within the distorted wave impulse approximation (DWIA) framework. We introduce a masking function which shows how the reaction amplitude in the nuclear interior is suppressed and defines the probed region of the $\alpha$ cluster wave function. It is clearly shown by means of the masking function that the $\alpha$ knockout reaction probes the $\alpha$ cluster amplitude in the nuclear surface region, which is the direct measure of well-developed $\alpha$ cluster states. A simplified form of the masking function is introduced and the incident energy dependence of the masking effect is investigated. $\alpha$ knockout reaction can probe the $\alpha$ cluster amplitude in the nuclear surface region by choosing proper kinematics owing to the masking effect originated from absorptions of distorting potentials, and is a suitable method to investigate how $\alpha$ cluster states are spatially developed.

6 pages, 6 figures

References in corpus (2)

• Linking structure and dynamics in $(p,pn)$ reactions with Borromean nuclei: the ${}^{11}$Li$(p,pn){}^{10}$Li case
• Benchmarking theoretical formalisms for $(p,pn)$ reactions: the ${}^{15}$C($p,pn$)${}^{14}$C case

Cited by in corpus (14)

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