Enhanced B_d⁰ → µ⁺µ^- Decay: What if?

Department of Physics, National Taiwan University, Taipei, Taiwan 10617

^a e-mail: wshou@phys.ntu.edu.tw

Abstract

If the very rare B_d⁰ → µ⁺µ^- decay is enhanced to (3–4)×10⁻¹⁰ level or higher, it can be discovered with existing 2011-2012 LHC data. It might then cast some doubt on the Higgs boson nature of the 126 GeV boson, since the likely explanation would be due to the fourth generation t^' quark. There is a mild motivation from the known tension in sin 2β/ϕ₁. If discovery is made before the 13 TeV run, then the b → d quadrangle (modulo m_t' would suddenly fall into our lap. Continued pursuit in future runs can probe below 3×10⁻¹⁰.