Abstract
We report total positronium formation cross sections for krypton with beam energies from the threshold region to 352.2 eV. The primary maximum at about 16 eV is followed by a small secondary maximum in the vicinity of 107 eV. There is, also, an increase in the rate of decline of the cross section with energy between 325 and 352 eV. We present estimates of total elastic scattering cross sections for argon and neon obtained by subtracting inelastic from total cross sections. In both cases the elastic cross section exhibits a dip just after the positronium formation threshold and a recovery in the neighborhood of the ionization threshold. We have tabulated positronium formation and proton electron capture cross sections and the ratios of the former to the latter for molecular hydrogen, helium, and krypton. In all cases the ratios climb steeply as particle velocity increases,the sharp rise beginning at appreciably lower velocities for hydrogen and krypton than for helium. We discuss initial work with the 3 m spectrometer and future measurements with it and the 2.3 m spectrometer.
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© 1987 Plenum Press, New York
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Diana, L.M., Coleman, P.G., Brooks, D.L., Chaplin, R.L. (1987). Studies of Inelastic Positron Scattering Using 2.3 and 3 M Spectrometers. In: Humberston, J.W., Armour, E.A.G. (eds) Atomic Physics with Positrons. NATO ASI Series, vol 169. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0963-5_5
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DOI: https://doi.org/10.1007/978-1-4613-0963-5_5
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