Determination of the longitudinal and the transverse part in π+ electroproduction

We report on an experiment where the different contributions from the transverse and longitudinal polarization of the virtual photon are measured separately for the reaction e^?p→e^?π⁺n. The data taken above the resonance region at small ∣t∣ values in the q² range of ∣q²∣ < 0.5 GeV² show a clear dominance of the longitudinal part of the cross section and are well described by a generalized Born-term model. Using this model the electromagnetic form factor of the pion is determined. At q² = ?0.35 GeV² one gets F_π = 0.598 ± 0.021.     

Novel heterocyclic derivatives of quinuclidine

Treatment of ethyl 3-quinuclidinone-2-carboxyIate (III) with appropriate reagents gave 2,3-fused heterocycles including pyrazolol, aminopyrimidinone, and aminopyridazinone types. The thiourea derivative of III could not be cyclized. Triazoline, pyrazoline, and isoxazoline derivatives were prepared by 1,3-dipolar cycloadditions to the 2- and 3-positions of methyl 2,3-dehydroquinuclidine-3-carboxylate (XIIIa). Such facile formation of cycloaddition products was not possible with 2,3-dehydroquinuclidine, which reacted only with phenylazide (in poor yield). Structural assignments for the products of cycloaddition were made by analogy, but alternative structures could not be ruled out by the nmr or mass spectra.     

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Light scattering from hydrogen and deuterium halides

Light scattering measurements along the coexistence line show that reorientation in liquid HCl, DCl, and HBr is strongly hindered at low temperature and collision limited on approaching the critical point. Discrepancies with NMR data are observed.     

Applications of a quantum virial theorem to kronig and penney's model and to a diatomic molecule in static approximation

Kronig and Penney's model is used to test a new formulation of quantum virial theorem for periodic systems. It is shown that the corrective term to the usual formulation of the virial theorem corresponding to boundary conditions is of importance and gives correct energy values for the system. Application of the virial theorem to a diatomic molecule also shows an important boundary condition correction if the distance of the nuclei is slightly different from equilibrium position, in accordance with the above correction.