6533b829fe1ef96bd128a3f6
RESEARCH PRODUCT
Form factors in the 'point form' of relativistic quantum mechanics : single and two-particle currents
Liang-gang LiuDe-hua WenDe-hua WenXian-ju WangGuo-tao LiuWei ChenBao-quan AiDong-qiao Dongsubject
PhysicsNuclear and High Energy PhysicsNuclear Theory010308 nuclear & particles physics[PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th]HyperonFOS: Physical sciencesSigmaRadiusAstrophysics01 natural sciencesOmegaNuclear Theory (nucl-th)High Energy Physics - PhenomenologyStarsNeutron starHigh Energy Physics - Phenomenology (hep-ph)Slow rotationProperty value[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]0103 physical sciences010306 general physicsdescription
Electromagnetic and Lorentz-scalar form factors are calculated for a bound system of two spin-less particles exchanging a zero-mass scalar particle. Different approaches are considered including solutions of a Bethe-Salpeter equation, a ``point form'' approach to relativistic quantum mechanics and a non-relativistic one. The comparison of the Bethe-Salpeter results, which play the role of an ``experiment'' here, with the ones obtained in ``point form'' in single-particle approximation, evidences sizable discrepancies, pointing to large contributions from two-body currents in the latter approach. These ones are constructed using two constraints: ensuring current conservation and reproducing the Born amplitude. The two-body currents so obtained are qualitatively very different from standard ones. Quantitatively, they turn out not to be sufficient to remedy all the shortcomings of the ``point form'' form factors evidenced in impulse approximation.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-01-01 |