Projectile deformation effects on single-nucleon removal reactions

Abstract

We discuss intermediate-energy single-nucleon removal reactions from deformed projectile nuclei. The removed nucleon is assumed to originate from a given Nilsson model single-particle state and the inclusive cross sections, to all rotational states of the residual nucleus, are calculated. We investigate the sensitivity of both the stripping cross sections and their momentum distributions to the assumed size of the model space in the Nilsson model calculations and to the shape of the projectile and residue. We show that the cross sections for small deformations follow the decomposition of the Nilsson state in a spherical basis. In the case of large and prolate projectile deformations the removal cross sections from prolate-like Nilsson states, having large values for the asymptotic quantum number n z , are reduced. For oblate-like Nilsson states, with small n z , the removal cross sections are increased. Whatever the deformation, the residue momentum distributions are found to remain robustly characteristic of the orbital angular momentum decomposition of the initial state of the nucleon in the projectile.

Neutron removal from the deformed halo nucleus Ne31

“…This result contrasts with those reported in Ref. [20] where no correlation between the cross sections and the rms radii of the Nilsson states has been found. In Fig.…”

“…On the other hand, Ref. [20] (see their Fig. 5) has shown that cross sections have some sensitivity to the relative sizes of the core and neutron wave function.…”

“…Theoretical studies of nucleon removal reactions from deformed projectiles have been reported previously [11,[17][18][19][20][21] and the longitudinal momentum distribution of stripping reactions has been calculated by using the Nilsson model. Glauber-type deformed potential S-matrices have been used in Ref.…”

“…[17], and the core-target S-matrix has been calculated in the absorbing-disk approximation [22] in Ref. [20]. In this work, we calculate the momentum distribution with orientation-dependent S-matrices obtained by the nuclear ground state densities and the nucleon-nucleon cross section [23][24][25].…”

Re-examining the transition into the N = 20 island of inversion: Structure of 30Mg

“…3 We believe that this is preferable to the commonly adopted procedure whereby the theoretical lineshapes are normalised to the peak of the experimental distribution. 4 These may arise from effects not incorporated in the model employed here [41,42], the choice of the model or formalism (see, for example, refs. [43,44]) and uncertainties in the parameters of the model itself.…”