arXiv subjects

C. W. Hwang

Publications and source records attributed to C. W. Hwang.

4 recordsLinked to original sources

arXiv2002

Lepton pair decays of the $K_L$ meson in the light-front model

We analyze $K_L$ lepton pair decays of $K_L \to l^+ł^-γ$ and $K_L \to l^+l^-l'^+l'^-$ $(l, l'=e, μ)$ within the framework of the light-front QCD approach (LFQA). With the $K_L \to γ^* γ^*$ form factors evaluated in a model with the LFQA, we calculate the decay branching ratios and find out that our results are all consistent with the experimental data. In addition, we study $K_L \to l^+l^-$ decays. We point out that our prediction on $K_L\to e^+e^-$ is about 20% smaller than that in the ChPT. We also discuss whether one could extract the short-distance physics from $K_L\to μ^+μ^-$.

hep-ph↗

arXiv2002

Study of Rare $B_c^+\to D_{d,s}^{(*) +}l\bar{l}$ Decays

We study the rare decays of $B_c^+\to D_{q}^{(*)+}l\bar{l}$ ($q=d,s$ and $l=ν_l,e,μ,τ)$ in the standard model. The form factors are evaluated in the light front and constituent quark models, respectively. We find that the decay branching ratios calculated in the two models for $B_c^+\to D^+_q l\bar{l}$ agree well with each other, whereas those for $B_c^+\to D_q^{*+}l\bar{l}$ are different.

hep-ph↗

arXiv2001

Mesonic Tensor Form Factors with Light Front Quark Model

We study the tensor form factors for $P \to P$ and $P \to V$ transitions in the light-front quark model with $P$ and $V$ being pseudoscalar and vector mesons, respectively. We explore the behaviors of these form factors in the entire physical range of $0\leq p^2\leq (M_i - M_f)^2$. At the maximum recoil of $p^2=0$, we compare our results of the form factors in $B\to π,K,ρ,K^*$ with various other calculations in the literature.

hep-ph↗

arXiv1996

$B -> πl ν$ Form Factors Calculated on the Light-Front

A consistent treatment of $B\rightarrow πl ν$ decay is given on the light-front. The $B$ to $π$ transition form factors are calculated in the entire physical range of momentum transfer for the first time. The valence-quark contribution is obtained using relativistic light-front wave functions. Higher quark-antiquark Fock-state of the $B$-meson bound state is represented effectively by the $|B^*π\rangle$ configuration, and its effect is calculated in the chiral perturbation theory. Wave function renormalization is taken into account consistently. The $|B^*π\rangle$ contribution dominates near the zero-recoil point ($q^2\simeq 25$ GeV$^2$), and decreases rapidly as the recoil momentum increases. We find that the calculated form factor $f_+(q^2)$ follows approximately a dipole $q^2$-dependence in the entire range of momentum transfer.

hep-ph↗