Anti-matter nuclei

If a radioactive nuclide has a neutron-to-proton ratio that is too low, placing it below the band of stability, it can move toward stability in one of two ways, positron emission or electron capture. Positron emission (P" ") is similar to beta emission, but in this case, a proton becomes a neutron and an anti-matter electron, or anti-elearon. The latter is also called a positron because, although it resembles an electron in most ways, it has a positive charge. The neutron stays in the nucleus, and the positron speeds out of the nucleus at high velocity, p n + e ... 

The decay of radioactive isotopes via electron emission, so-called beta decay, is a well-known phenomenon, hi this mode imstable nuclei that have an excessive number of neutrons, for example can emit fast electrons, particles, in order to attain a stable nuclear configuration. Nuclei with insufficient neutrons, such as can obtain stability by emitting fast positrons, particles (the anti-matter equivalents of electrons). Both processes are classified as radioactive f) decay. In each case, the mass munber of the nucleus remains constant but the atomic number changes. There exist several positron emitting isotopes, of which and in particular... 

In the present context, however, the condition Uv — Us — 2Mb = 0 is desired for baryon anti-baryon pair creation [27] above the critical density. To achieve the higher density we gave up the self-consistent calculations and followed a crude method we compressed the Pb nucleus to 2, 4, 6, and 8.5 times normal nuclear matter density by scaling the vector density with a scaling factor c and the radius with the factor c to keep baryon number conserved. The. scalar potential was scaled with the corresponding nuclear matter factor as follows we calculated the scalar potential Us pv) for nuclear matter as a function of density (see Fig. 3, dotted curve), scaled the vector density p by a factor c to cp . Now from Fig. 3 we took the value of Us which corresponds to the density cp . For example, at p = 8po (i.e. p — 1-16 fm ) the value... 

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