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Formation of 24Mg* in the Splitting of 28Si Nuclei by 1-GeV Protons

A. A. Vasenko·N. D. Galanina·K. E. Gusev·V. S. Demidov·E. V. Demidova·I. V. Kirpichnikov·A. Yu. Sokolov·A. S. Starostin·N. A. Khaldeeva
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Abstract

The 28Si(p, p' gamma)24Mg reaction has been studied at the ITEP accelerator by the hadron-gamma coincidence method for a proton energy of 1 GeV. Two reaction products are detected: a 1368.6-keV gamma-ray photon accompanying the transition of the 24Mg* nucleus from the first excited state to the ground state and a proton p' whose momentum is measured in a magnetic spectrometer. The measured distribution in the energy lost by the proton in interaction is attributed to five processes: the direct knockout of a nuclear alpha cluster, the knockout of four nucleons with a total charge number of 2, the formation of the DeltaSi isobaric nucleus, the formation of the Delta isobar in the interaction of the incident proton with a nuclear nucleon, and the production of a pi meson, which is at rest in the nuclear reference frame. The last process likely corresponds to the reaction of the formation of a deeply bound pion state in the 28P nucleus. Such states were previously observed only on heavy nuclei. The cross sections for the listed processes have been estimated.

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A. A. Vasenko, N. D. Galanina, K. E. Gusev, V. S. Demidov, E. V. Demidova, I. V. Kirpichnikov, A. Yu. Sokolov, A. S. Starostin, N. A. Khaldeeva. 2006-09-01. Formation of 24Mg* in the Splitting of 28Si Nuclei by 1-GeV Protons. https://doi.org/10.1134/s002136400610002x%2010.1134%2Fs0021364006180172

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