# Neutron quadrupole transition strength in $^{10}$C deduced from the $^{10}$C$(\alpha,\alpha')$ measurement with the MAIKo active target

## TL;DR

This study measured alpha scattering on $^{10}$C using the MAIKo active target to determine the neutron quadrupole transition strength, revealing insights into the nuclear structure and neutron-proton transition ratio.

## Contribution

The paper introduces a novel measurement of neutron quadrupole transition strength in $^{10}$C using alpha scattering with the MAIKo active target, providing new data on nuclear deformation.

## Key findings

- Neutron transition matrix element $M_{n} = 6.9 \, ext{fm}^2$ with uncertainties.
- Neutron-to-proton transition ratio $M_{n}/M_{p} = 1.05$ indicating less neutron dominance.
- Effective $ ext{alpha}$-$N$ interaction and density distribution determined from elastic scattering.

## Abstract

Elastic and inelastic alpha scatterings on $^{10}$C were measured using a 68-MeV/u radioactive $^{10}$C beam incident on the recently developed MAIKo active target system. The phenomenological effective $\alpha$-$N$ interaction and the point-nucleon density distribution in the ground state were determined from the elastic scattering data. The cross sections of the inelastic alpha scattering were calculated using this interaction and density distribution and were compared with the experiment to determine the neutron quadrupole transition matrix element $M_{n}$ between the ground state and the $2_{1}^{+}$ state at $E_{x} = 3.35$ MeV in $^{10}$C. The deduced neutron transition matrix element is $M_{n} = 6.9\, \pm0.7\, \mathrm{(fit)}\, \pm1.2\, \mathrm{(sys)}$ fm$^{2}$. The ratio of the neutron transition strength to proton transition strength was determined as $M_{n}/M_{p} = 1.05\, \pm0.11\, \mathrm{(fit)}\, \pm0.17\, \mathrm{(sys)}$, which indicates that the quadrupole transition between the ground state and the $2_{1}^{+}$ state in $^{10}$C is less neutron dominant compared to that in $^{16}$C.