13 B$_{K}$ = 0 . 72 ± 0 . 05 [62] $_{f$_{bs}$}$√$_{B}$$_{bs}$ = 0 . 281 ± 0 . 021 GeV [65] Δ M$_{s}$ = (17 . 77 ± 0 . 12) ps − 1 [66] Δ M$_{d}$ = (0 . 507 ± 0 . 005) ps − 1 ξ$_{s}$ = 1 . 2 ± 0 . 06 [65] γ = (75 . 0 ± 22 . 0) ◦ | ϵ$_{k}$ | × 10 3 = 2 . 32 ± 0 . 007 sin 2 β$_{ψK}$$_{s}$ = 0 . 672 ± 0 . 024 Br ( K + → π $^{+}$νν ) = (0 . 147 +0 . 130 − 0 $_{089}$) × 10 − 9 Br ( B → X$_{c}$ℓν ) = (10 . 61 ± 0 . 17) × 10 − 2 Br ( B → X$_{s}$γ ) = (3 . 55 ± 0 . 25) × 10 − 4 Br ( B → X$_{s}$ℓ $^{+}$ℓ − ) = (0 . 44 ± 0 . 12) × 10 − 6 R$_{bb}$ = 0 . 216 ± 0 . 001 ( High q 2 region ) | V$_{ub}$ | = (37 . 2 ± 2 . 7) × 10 − 4 | V$_{cb}$ | = (40 . 8 ± 0 . 6) × 10 − 3 η$_{c}$ = 1 . 51 ± 0 . 24 [67] η$_{t}$ = 0 . 5765 ± 0 . 0065 [58] η$_{ct}$ = 0 . 47 ± 0 . 04 [68] m$_{t}$ = 172 . 5 GeV T$_{4}$ = 0 . 11 ± 0 . 14 TABLE III: Inputs that we use in order to constrain the SM4 parameter space, we have considered the 2 σ range for V$_{ub}$ . and X$_{1}$ ( x ) is the QCD correction. The expression for X$_{1}$ ( x ) is given in [56]. The function X can also be written as Here η$_{X}$ represents the NLO corrections. The function X l NL is the function corresponding to X ( x$_{t}$ ) in the charm sector. It results from the NLO calculations and its explicit form is given in [60, 69]. The branching fraction of K + → π $^{+}$ν ¯ ν can be written as follows where and r$_{K}$$_{+}$ = 0 . 901 summarizes the isospin breaking corrections in relating the K + → π $^{+}$ν ¯ ν to the well measured leading decay K + → π $^{0}$e$^{+}$ν . κ + = r$_{K}$$_{+}$ 3 α $^{2}$Br ( K + → π $^{0}$e$^{+}$ν ) 2 π $^{2}$sin$^{4}$Θ$_{W}$ λ 8 , (42) P$_{0}$ ( X ) = 1 λ 4 [ 2 3 X e NL + 1 3 X τ NL ] , (43) Br ( K + → π $^{+}$ν ¯ ν ) = κ$_{+}$ [( Im λ$_{t}$ λ 5 X ( x$_{t}$ ) + Im λ$_{t}$ ′ λ 5 X ( x$_{t}$ ′ ) ) 2 + ( Re λ$_{c}$ λ P$_{0}$ ( X ) + Re λ$_{t}$ λ 5 X ( x$_{t}$ ) + Re λ$_{t}$ ′ λ 5 X ( x$_{t}$ ′ ) ) $^{2}$] , (41) X ( x$_{t/t}$ ′ ) = η$_{X}$.X$_{0}$ ( x$_{t/t}$ ′ ) , η$_{X}$ = 0 . 994 . (40)