New Physics in $B_q^0-{\bar{B}}_q^0$ Mixing: Present Challenges, Prospects, and Implications for $B_q^0\to {\mu }^{+}{\mu }^{-}$

Abstract

The phenomenon of $B_q^0-{\bar{B}}_q^0$ mixing ($q=d,s$) provides a sensitive probe for physics beyond the Standard Model. We explore the corresponding space for New Physics left through the current data, having a careful look at analyses of the Unitarity Triangle that are needed for the Standard Model predictions of the $B_q$ mixing parameters. In particular, we explore the impact of tensions between inclusive and exclusive determinations of the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$. Moreover, we focus on the angle $\gamma$ of the Unitarity Triangle, comparing measurements from $B\to DK$ and $B\to \pi \pi$, $\rho \pi$, $\rho \rho$ decays, where the latter are typically interpreted in terms of the angle $\alpha$. We discuss various scenarios and present the corresponding state-of-the-art constraints on the New Physics parameters of $B_q^0-{\bar{B}}_q^0$ mixing. We point out that these results have an interesting application in the analysis of rare $B_q^0\to {\mu }^{+}{\mu }^{-}$ decays, allowing us to minimise the impact of CKM parameters in the search for New Physics. In view of the high-precision era, we make future projections. Interestingly, we find that for the extraction of the New Physics parameters in the $B_d$ system the determination of the apex of the Unitarity Triangle results in a key limiting factor. By contrast, the corresponding impact is negligible for the $B_s$ system, making it a promising candidate to reveal sources of New Physics.

45 pages, 14 figures and 6 tables. This version matches the published version

References in corpus (25)

• FLAG Review 2021
• Probing New Physics via the $B_s^0\to {\mu }^{+}{\mu }^{-}$ Effective Lifetime
• Current status of the Standard Model CKM fit and constraints on $\Delta F=2$ New Physics
• Anatomy of New Physics in B-Bbar mixing
• $\Delta M_s$ theory precision confronts flavour anomalies
• Inclusive semileptonic B decays and the determination of |V_ub|
• Probing New Physics through B Mixing: Status, Benchmarks and Prospects
• Three loop calculations and inclusive $V_{cb}$
• Implications of new evidence for lepton-universality violation in $b\to s{\ell }^{+}{\ell }^{-}$ decays
• Analysis of neutral $B$-meson decays into two muons
• More Indications for Lepton Nonuniversality in $b\to s{\ell }^{+}{\ell }^{-}$
• Semitauonic $b$-hadron decays: A lepton flavor universality laboratory
• Measurement of the CKM angle $\gamma$ from a combination of LHCb results
• Simultaneous determination of CKM angle $\gamma$ and charm mixing parameters
• New physics in $B$ meson mixing: future sensitivity and limitations
• Flavor Anomalies in Heavy Quark Decays
• The Exclusive Vision of Rare $K$ and $B$ Decays and of the Quark Mixing in the Standard Model
• Exploiting dijet resonance searches for flavor physics
• First observation of the decay $B_s^0\to K^{-}{\mu }^{+}{\nu }_{\mu }$ and a measurement of $|V_{ub}|/|V_{cb}|$
• In Pursuit of New Physics with $B_d^0\to J/\psi K^0$ and $B_s^0\to J/\psi \varphi$ Decays at the High-Precision Frontier
• Update on $|V_{us}|$ and $|V_{us}/V_{ud}|$ from semileptonic kaon and pion decays
• Complete theory of radiative corrections to $K_{\ell 3}$ decays and the $V_{us}$ update
• Searching for New Physics with $\overline{\mathcal{B}}(B_{s,d}\to \mu \bar{\mu })/\Delta M_{s,d}$
• Mapping out the Space for New Physics with Leptonic and Semileptonic $B_{(c)}$ Decays
• Using $B_s^0\to D_s^{\mp }{K}^{\pm }$ Decays as a Portal to New Physics

Cited by in corpus (6)

• Flavor Changing Neutral Current processes and family discrimination in 3-3-1 models
• New Perspectives for Testing Electron-Muon Universality
• $\Delta S=2$ nonleptonic hyperon decays as probes of new physics
• How to tame penguins: Advancing to high-precision measurements of ${\varphi }_d$ and ${\varphi }_s$
• Targeting (Pseudo)-Scalar CP Violation with $B_s\to {\mu }^{+}{\mu }^{-}$
• Three decades of FCNC studies in 3-3-1 model with right-handed neutrinos: from $Z^{\prime }$-dominance to the alignment limit