Recent Developments in High-Energy Physics pp 277-287 | Cite as

# Selection Rules for Baryon Number Nonconservation in Gauge Models

Chapter

## Abstract

We discuss the selection rules for baryon number nonconserving processes in the context of various gauge models with partial and complete unification of all elementary particle forces. Three separate cases are discussed: (a) Δ(B−L) = 0, Δ(B+L) ≠ 0; (b) Δ(B−L) ≠ 0, Δ(B+L) = 0; and (c) Δ(B−L) ≠ 0 and Δ(B+L) ≠ 0. Observation of \(n - \bar n\) “oscillation” without proton decay with a life-time of ≳ 10^{30} years would be evidence of “partial unification” with an intermediate mass scale of ~10^{8}–10^{9} GeV.

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### References and Footnotes

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- 17.This is the subject of a forthcoming paper by R.N. Mohapatra and G. Senjanovic, to appear as a City College Preprint (1980). It is shown in this paper that to get sin
^{2}0_{W}(m_{wL}) to be about 0.23, while at the same time getting an intermediate mass scale, requires the value m_{X,Y}≈ 10^{19}GeV and m_{WR}≈10 GeV, as well as m_{X,Y}.. m_{PS}. In this case, the proton decay mediated by the gauge bosons is completely suppressed leaving n–n oscillation as a possible dominant mode of baryon non- conservation.Google Scholar - 18.HUTP-79/AO29 and HUTP-79/A059. These preprints discuss modifications of the minimal SU(5) model and reach similar conclusions to ours as summarized in Table 1; however, we stress that the new result highlighted by Table 1 is the predicted dominance of the “neutron oscillation” mode in a partial unification model incorporating B-L local symmetry on the electroweak level.Google Scholar

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© Plenum Press, New York 1980