Nuclear quadrupole-quadrupole interaction in the inelastic scattering of aligned deuterons from deformed nuclei

Abstract

The 2~--excitation of deformed nuclei by tensor polarized deuterons provides an alignment of both nuclei and thus a means to study specifically the quadrupole-quadrupole interaction between both nuclei. The tensor analyzing power A=(O) has been measured for the elastic and inelastic scattering on 24Mg and ZsSi. The coupled channel analysis including a deformed tensor potential reveals a clear signature of the quadrupole-quadrupole part of the nuclear projectile-target interaction.

On the tensor term in the deuteron optical potential nearE d =20 MeV

“…Keeping in mind that the folding calculations for T21(0) have no adjustable parameters, the solid lines in Fig. 4 actually provide a quite satisfactory description of the data (see also [11] for 24Mg and 2SSi), which means that for these nuclei the essential features in T2~(0) are reproduced by the imaginary folding TR-potential. The inclusion of the real folding TR-potential on the other hand worsens the description in all cases substantially.…”

“…The importance of channel coupling effects to vibrational states is demonstrated in Fig. 5, where the solid lines show calculations for the elastic scattering on b~ including the channel coupling to the 3-vibrational state using a deformed central deformed spin orbit and a deformed imaginary tensor potential [11]. The dotted lines show by contrast the same calculations without channel coupling.…”

“…By the use of the empirical deuteron potential instead of the nucleon optical potentials in (2) -as proposed in [11] -all dynamical effects, which contribute to the deuteron S and D state in the same way, are taken into account phenomenologically.…”

“…Furthermore, the dependence of the elastic scattering on the coupling to collective inelastic excitations has been investigated. For the deformed nuclei 24Mg and 28Si the importance of channel coupling to the tensor analyzing power of the elastic scattering channel and the necessity of a deformed tensor potential for the reproduction of inelastic tensor analyzing powers has been discussed already in an earlier publication [11]. With respect to the behaviour of very light nuclei we refer to previous work on 4He [12].…”

An inversion procedure for coupled-channel scattering: determining the deuteron-nucleus tensor interaction

“…The overall general success of folding models for central and spin-orbit interactions suggests that folding model calculations of V R (r) should give at least approximately the correct radial form and overall magnitude, but this has not been borne out in the case of T R according to extensive phenomenological studies, e.g. [20][21][22][23][24]. The overall conclusion is that the real part of V R (r) predicted by the folding model is much too strong for heavy nuclei, of the right order of magnitude for light target nuclei, and actually about three times too strong for a 4 He target.…”