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

• Published in: arXiv.org 2006-09
• Main Authors: Vasenko, A A, Galanina, N D, Gusev, K E, Demidov, V S, Demidova, E V, Kirpichnikov, I V, A Yu Sokolov, Starostin, A S, Khaldeeva, N A
• Format: Article
• Language: English
• Subjects: Energy distribution; Energy measurement; Gamma rays; Heavy nuclei; Nuclei (nuclear physics); Nucleons; Pions; Proton energy; Reaction products
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.0609001

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.