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arXiv · 1102.2699

Electromagnetic production of hypernuclei

B. I. S. van der Ventel·T. Mart·H. -F. Lu·H. L. Yadav·G. C. Hillhouse
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Abstract

A formalism for the electromagnetic production of hypernuclei is developed where the cross section is written as a contraction between a leptonic tensor and a hadronic tensor. The hadronic tensor is written in a model-independent way by expanding it in terms of a set of five nuclear structure functions. These structure functions are calculated by assuming that the virtual photon interacts with only one bound nucleon. We use the most recent model for the elementary current operator which gives a good description of the experimental data for the corresponding elementary process. The bound state wave functions for the bound nucleon and hyperon are calculated within a relativistic mean-field model. We calculate the unpolarized triple differential cross section for the hypernuclear production process e + 12C --> e + K+ + 12_Lambda{B} as a function of the kaon scattering angle. The nuclear structure functions are calculated within a particle-hole model. The cross section displays a characteristic form of being large for small values of the kaon scattering angle with a smooth fall-off to zero with increasing angle. The shape of the cross section is essentially determined by the nuclear structure functions. In addition, it is found that for the unpolarized triple differential cross section one structure function is negligible over the entire range of the kaon scattering angle.

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B. I. S. van der Ventel, T. Mart, H. -F. Lu, H. L. Yadav, G. C. Hillhouse. 2011-02-14. Electromagnetic production of hypernuclei. https://doi.org/10.1016/j.aop.2011.02.003

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