model that are important for mixing.

### $B \rightarrow X_s \, \gamma$ Constraints

Of course the two scalar doublet model also gives new contributions to quantities that are not $\rm CP$ violating. Here we briefly review the constraints on this model from $B \rightarrow X_s \, \gamma$ with these assumptions. The extra term in the effective Hamiltonian arises from charged scalar exchange and has the form, \_[[|[B]{}]{}X\_s ]{} = \[V\_[ts]{}\^ V\_[tb]{}\] C\_ ( |[s]{}\_L \_[ ]{} F\^[ ]{} b\_R ), where $e < 0$ is the electric charge. The Wilson coefficient is given by C\_= \_U\^ \_D\^ ( ) , with f\_(x) = ( ) - ( ). This operator’s contribution to the measured branching fraction ${\rm BR}(\bar{B} \rightarrow X_s \, \gamma)_{E_\gamma > 1.6 \, {\rm GeV}}$ is known [@Grzadkowski:2008mf] = 3.15 0.23 - 4.0 v\^2 C\_. This constraint includes the effect of running this operator down to the scale $m_b$. Comparing to the world experimental average [@Barberio:2007cr] we obtain a $1 \sigma$ bound on the parameters of the form -0.17 &lt; Re\[\_U\^ \_D\^\] f\_(m\_t\^2/m\_[S\^]{}\^2) &lt; 0.07. For $m_{S^\pm} = 360 ~{\rm GeV}$ we find $-1.7 < {\rm Re}[\eta_U^\star \eta_D^\star]   < 0.7$. Although this constraint is weak it is interesting 