Gamow-Teller strength in Na23(n,p) and a comparison to Na23(-,)

We report measurements of the Na23(n,p) differential cross section at an incident energy of 198 MeV and angles from 0° to 24° using the TRIUMF Charge Exchange Facility. From these data we determine Gamow-Teller (GT) transition probabilities to low lying 1/2+, 3/2+, and 5/2+ Ne23 states and the GT+ strength distribution up to 25 MeV excitation energy. The values of BGT+ to discrete states, and the GT+ strength below 10 MeV, are found to be in reasonable agreement with a full 1s-0d shell model calculation with a normalization factor of about 0.74. The GT+ strength above 10 MeV suggests the removal of strength from lower to higher excitation energies. We also compare the Na23(n,p) data with Na23(-,) data and find agreement between the values of BGT+ to discrete levels extracted from the (n,p) and (-,) reactions. The general consistency of the (n,p) and (-,) data, and the full 1s-0d shell model calculation, give confidence in a recent extraction of the weak pseudoscalar coupling from - capture on Na23. Finally, using both - decay and - capture data, we obtain unit cross sections from the Na23(n,p) measurement.