Interaction cross section study of the two-neutron halo nucleus 22 C

Examination of the C22 radius determination with interaction cross sections

“…We discuss the sensitivity of the spatially extended halo tail to the total reaction cross sections. The root-mean-square matter radius obtained in this study is consistent with that extracted from the recent cross-section measurement on 12 C target. We show that the simultaneous reproduction of the two recent measured cross sections is not feasible within this framework.…”

“…In Sec. IV A, the validity of our calculations is confirmed in comparison with available experimental data of 12 C + 12 C and 12 C + 1 H systems. Then, we further confirm the reliability of our calculations in the reactions involving 20 C and 12 C. Section IV B presents our main results: We describe the 22 C + 12 C and 22 C + 1 H reactions in a consistent manner and discuss the possible uncertainties in the radius determination using the interaction cross section.…”

“…The large interaction cross section on 1 H target incident at 40 MeV/nucleon was measured 1338 ± 274 mb, resulting in a huge matter radius of 5.4 ± 0.9 fm with large uncertainties. Recently, high-precision measurement was made for the interaction cross section on 12 C target incident at ∼240 MeV/nucleon by Togano et al [12], and the resultant root-mean-square (rms) matter radius is 3.44 ± 0.08 fm, which is quite far from the previously extracted value 5.4 ± 0.9 fm [11]. Since the nuclear radius has often served as one of the inputs to some theoretical models, e.g., Refs.…”

“…Use of such inclusive observables has some advantages: The theory of describing the cross section is well established, the cross sections can be measured for almost all nuclei as long as the beam intensity is sufficient, and the different sensitivity to the nuclear density profile can be controlled by a choice of a target nucleus and an incident energy. Systematic analyses of nuclear matter radii with the total reaction cross sections on 12 C target incident at 200 MeV/nucleon have revealed structure changes and the role of excess neutrons of light neutron-rich unstable nuclei [14][15][16][17][18][19][20][21]. We remark that the total reaction cross sections on 1 H target is also useful because the probe has different sensitivity to protons and neutrons in the projectile nucleus depending on incident energies that can be used to extract the neutron-skin thickness of unstable nuclei [22,23].…”

Superfluid Fermi atomic gas as a quantum simulator for the study of the neutron-star equation of state in the low-density region

“…However, the determination of the EoS by astronomical observations is difficult, because even the known nearest neutron star (RX J1856.5-3754) is about 400 lightyears away from Earth [46]. Although neutron skins [47,48] and hallows [49,50] in neutronrich nuclei give information about neutron matter, it is still not enough to construct the neutron-star EoS, including the many-body effects associated with a strong neutron-neutron interaction [33]. As a result, the current approach to the neutron-star EoS has to strongly rely on theory [51][52][53][54].…”