Penguin-Diagram Induced $B\to K_X\varphi$ Decays in the Standard Model and in the Two-Higgs-Doublet Model

We systematically analyse the gluonic penguin-induced charmless decays $B \ra K_X\phi$($K_X$denotesthemesonstate$s\bar q ;(q=u\ {\rm or}\ d)$ ), in the standard model and the two-Higgs-doublet model. These processes, being induced at one-loop level, are of great importance in measuring the virtual top quark effect in the standard model, and also in searching for the non-standard signals in the low energy region. It is shown that the QCD effect is also significant in these processes, as in the weak radiative processes $B \ra X_s \gamma$. We also show that the charged Higgs contribution can not provide sizable enhancements for the decays $B\text{ra}{K}_X\varphi$, in contrast to the decays $B\text{ra}{K}_X\gamma$. It is also found that processes such as $B \ra K_1(1400)\phi$and$B \ra K(1460)\phi$havelargebranchingfractionsamong$B \ra K_X\phi$ decays.