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gies shows that the quenching is the same at low and at high excitation energies. A comparison of figures 7 and 8 shows that no major proton groups are missing in ta- ble II and basically all strength is identified in the peaks. If this were not the case, the second procedure arriving at figure 8 should yield more B(GT) strength than the procedure which produces the spectrum of figure 7. 

Under the assumption of allowed transitions, all lev- els populated in the β decay of $^{33}$Ar (I π = 1/2 $^{+}$) have spin/parity 1/2 + or 3/2 $^{+}$. However, certain characteris- tics observed in the present study may allow to distin- guish between these two possibilities. We will use the observed proton lines to propose spins for some levels. This will be discussed in the following. 

Proton emission from a nuclear state is governed by two effects: the barrier penetration and the spatial over- lap of the initial and the final states. For a given nucleus, the barrier penetration depends on the energy available for the proton and the barrier height. The contribution of the Coulomb barrier is the same for all states and all emissions. However, for a transition with a non-zero angular momentum, the angular momentum barrier is added. Therefore, proton transitions to the ground state are favored by the available energy, except if angular mo- mentum has to be ”carried away” by the proton. If states emit protons only to an excited state in the proton daugh- ter nucleus, this can be an indication that this transition has a lower angular momentum than the ground state transition, a fact which would enable us to distinguish between two possible spin assignments. 

Such an assignment, however, neglects the possibility that strongly different overlaps of the initial and final wave functions can have a similar effect. In principle, model calculations would have to be performed for all states involved before such an assignment can be made. We believe that this is not very meaningful, as the states calculated e.g. in shell-model calculations might differ strongly from the observed states, even if the excitation energy is equivalent. + 

We assign tentatively a spin of 3/2 to all states which decay only to the first excited state in the proton- daughter nucleus $^{32}$S. We give these spin/parities in parenthesis to make clear that this is a tentative assign- ment. + 

The states at 7762 keV and at 8491 keV decay to the 0 ground state and the 0 + second excited state. This indi- cates that the emitting state has most likely a spin/parity of 1/2 + which yields an ℓ = 0 proton emission. 

For other states, barrier penetration calculations (see table V) may elucidate the situation. The barrier pen- etration is calculated from Coulomb wave functions [30] which yields partial half-lives for both spin possibilities for decays to the ground and excited states. The ratios of the partial half-lives for emission to the ground and 

## C. Spins and parities 

