Indirect constraints on third generation baryon number violation

Abstract

Abstract The non-observation of baryon number violation suggests that the scale of baryon-number violating interactions at zero temperature is comparable to the GUT scale. However, the pertinent measurements involve hadrons made of the first-generation quarks, such as protons and neutrons. One may therefore entertain the idea that new flavour physics breaks baryon number at a much lower scale, but only in the coupling to a third generation quark, leading to observable baryon-number violating b-hadron decay rates. In this paper we show that indirect constraints on the new physics scale ΛBNV from the existing bounds on the proton lifetime do not allow for this possibility. For this purpose we consider the three dominant proton decay channels p → ℓ + ν ℓ ν ¯ $$ {\ell}^{+}{\nu}_{\ell}\overline{\nu} $$ , p → π + ν ¯ $$ {\pi}^{+}\overline{\nu} $$ and p → π 0 ℓ + mediated by a virtual bottom quark.

Keywords

• Baryon/Lepton Number Violation
• Bottom Quarks
• SMEFT