a Measurement of the Deuteron Quadrupole Moment by Elastic Scattering of Polarized Deuterons
The quadrupole moment of the deuteron, Q, was determined to a relative accuracy of (+OR-)7% from measurements of T(,20) for ('208)Pb(d,d) at a deuteron bombarding energy of 4 MeV. This bombarding energy is sufficiently far below the Coulomb barrier that T(,20) results primarily from the electrostatic interaction between the quadrupole moment of the deuteron and the gradient of the electric field of the target nucleus. To a good approximation, T(,20) is linear in Q. In order to determine the quadrupole moment, the 4 MeV measurements were compared to quantum mechanical calculations of T(,20), accurate to order Q('2), for the electric quadrupole interaction. The results were corrected for the deuteron electric polarizability, atomic screening of the nuclear charge, vacuum polarization, and relativistic effects. In order to investigate the effects of nuclear interactions on deuteron scattering at 4 MeV, the tensor analyzing powers for ('208)Pb(d,d) were calculated with the distorted-wave theory and with the optical model for a range of sub-Coulomb bombarding energies. The calculated values were checked by comparing them to measurements of an excitation function of T(,20) for E(,d) = 4 to 9 MeV and angular distributions of the analyzing powers at E(,d) = 8 MeV. Both models explained the measurements and were used to calculate the tensor analyzing powers at 4 MeV. It was found that nuclear effects are negligible at 4 MeV for the purposes of this experiment. The final result, Q = 0.285 (+OR-) 0.020 fm('2), is consistent with the value obtained from atomic physics.
- Pub Date:
- Physics: Nuclear