Neutron-rich rare isotope production with stable and radioactive beams in the mass range A ∼ 40–60 at beam energy around 15 MeV/nucleon

Abstract

We studied the production of neutron-rich nuclides in multinucleon transfer collisions of stable and radioactive beams in the mass range A∼40-60. We first presented our experimental cross section data of projectile fragments from the reaction of 40 Ar(15 MeV/nucleon) with 64 Ni, 58 Ni and 27 Al. We then compared them with calculations based on either the deep-inelastic transfer (DIT) model or the constrained molecular dynamics (CoMD) model, followed by the statistical multifragmentation model (SMM). An overall good agreement of the calculations with the experimental data is obtained. We continued with calculations of the reaction of 40 Ar (15 MeV/nucleon) with 238 U target and then with reactions of 48 Ca (15 MeV/nucleon) with 64 Ni and 238 U targets. In these reactions, neutron-rich rare isotopes with large cross sections are produced. These nuclides, in turn, can be assumed to form radioactive beams and interact with a subsequent target (preferably 238 U), leading to the production of extremely neutron-rich and even new isotopes (e.g. 60 Ca) in this mass range. We conclude that multinucleon transfer reactions with stable or radioactive beams at the energy of around 15 MeV/nucleon offer an effective route to access extremely neutron-rich rare isotopes for nuclear structure or reaction studies.

Microscopic dynamical description of multinucleon transfer in 40Ar induced peripheral collisions at 15 MeV/nucleon

“…Data were obtained in a series of successive magnetic rigidity settings of the spectrometer in the range of 1.1-1.5 Tm. We note that this magnetic rigidity range did not fully cover the neutron deficient side of the product distribution which extends down to 0.8 Tm according to our calculations [10]. The protonrich isotopes with incomplete magnetic rigidity coverage are to the left of the thin solid lines in Fig.…”

“…These excitation energies are reported on some of the peaks of the experimental momentum distributions and help us appreciate the degree of dissipation that is involved. We note that the experimental mass distributions have been obtained and presented in our previous work [10].…”

“…The experimental data on neutron rich nuclide production presented in this work were obtained at the Cyclotron Institute of Texas A&M University and are presented in detail in [9,10]. In this work we give a brief description of the experimental set-up.…”

“…In fig. 1, we present the experimental data for the momentum distributions for the reaction 40 Ar with 64 Ni and 58 Ni targets at 15 MeV/nucleon that were extracted as part of this work employing the original data [10]. We note that the horizontal axis of the momentum distributions gives momentum per nucleon, which essentially represents velocity.…”

“…2, we present the mass distributions for the reaction 40 Ar (15 MeV/nucleon) with 64 Ni. The experimental data [10] are shown with the full black points. The region of isotopes to the left of the thin solid lines corresponds to incomplete data coverage as explained in section 2.…”