arXiv subjects

Zuo-Hong Li

Publications and source records attributed to Zuo-Hong Li.

21 records · Page 2Linked to original sources

arXiv2001

Improved approach to the heavy-to-light form factors in the light-cone QCD sum

A systematic analysis shows that the main uncertainties in the form factors are due to the twist-3 wave functions of the light mesons in the light-cone QCD sum rules. We propose an improved approach, in which the twist-3 wave functions doesn't make any contribution and therefore the possible pollution by them can be avoided, to re-examine $B \to π$ semileptonic form factors. Also, a comparison between the previous and our results from the light-cone QCD sum rules is made. Our method will be beneficial to the precise extracting of $\mid{V_{ub}}\mid$ from the experimental data on the processes $B \to π\ell \widetilde{ν_\ell}$.

hep-ph↗

arXiv1999

Some Remarks on the Final State Interactions in $B\to πK$ Decays

Careful discussions are made on some points which are met in studying B decay final state interactions, taking the $B^0\to π^+ K^-$ process as an example. We point out that $π$--exchange rescatterings are not important, whereas for $D^*$ and $D^{**}$ exchanges, since the $B^0\to D^+D_s^-$ decay has a large branching ratio their contributions may be large enough to enhance the $B\to πK$ branching ratio significantly. However our estimates fail to predict a large enhancement.

hep-ph↗

arXiv1996

QCD Sum Rules for The Double Ratio $(f_{B_s}/f_{B_d}) /(f_{D_s}/f_{D_d})$ in HQET

The double ratio $(f_{B_s}/f_{B_d})/(f_{D_s}/f_{D_d})$ is calculated by QCD sum rules in heavy quark effective theory (HQET), both numerically and analytically. Our expression for the double ratio shows explicitly the dependence on the light quark masses, the heavy quark symmetry breaking and the vacuum condensates. The numerical result favors the double ratio to be a little greater than 1.

hep-ph↗