Abstract
From a solution of the problem of magnetic moments of the nuclei3H and3He, two properties are obtained:
- These nuclei have mixed orbital ground states.
- These states are not charge symmetric.
The first property is expected to hold also for baryons in the quark model, on account of recently measured magnetic moments. Supporting evidence and implications for baryon structure are discussed.
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See e.g. [2]. It is significant that examples are known of systems, bound by strong interactions, for which exchange moments are an unnecessary complication (e.g. the deuteron)
It is instructive to read in [2], p. 191, that for nuclei more complex than H3, He3. “... it is desirable, just as for complex atoms, to introduce some simplifying assumption, known as 〈coupling scheme〉...”. Sequential schemes were not even mentioned for H3, He3. This situation has not changed since then
These tests involve the ratio of differential cross sections of the reactionspd→H3 π + andpd→He3 π 0.
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In a variety of model calculations involving meson exchanges and/or isobar configurations the corresponding current contributions to elastic e.m. form factors tend to vanish in the limit of zero momentum transferq 2. By definition the value ofF m(q 2=0) agrees with the measured magnetic moment. This supports our assumption 1., i.e. absence of exchange moments in the static case. Nonetheless at ¦q 2¦values above 0.5 GeV2 substantial contributions are found necessary e.g. to explain the observed dip-structures, see e.g. [14] and proceedings of the Ninth International Conference on the Few Body Problem, Ed. Levin, F.: Nucl. Phys. A353 (1981). The question how the result (4) for theA=3 wave functions is related to theA=3 form factors cannot be answered without considering the radial parts of these wave functions and without knowing their precise connection with the form factors. In the above analysis these radial parts could be left out of consideration. The measured form factors somehow put constraints on them. It is interesting to speculate that e.m. nucleon form factors will also exhibit dip structure atq 2 values where virtualq¯q pairs are probed in elasticeN scattering (¦q 2¦≳50 GeV2)
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Comments of A.N. Diddens, K.J.F. Gaemers, J.C. Kluyver and B. de Wit are gratefully acknowledged.
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Wolters, G.F. Magnetic moments and structure of the nuclei3H,3He and of baryons. Z Physik A 306, 33–36 (1982). https://doi.org/10.1007/BF01413404
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DOI: https://doi.org/10.1007/BF01413404