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Yuan-ben Dai

Publications and source records attributed to Yuan-ben Dai.

8 recordsLinked to original sources

Subleading Isgur-Wise form factors and O(1/m_Q) corrections to the semileptonic decays B->D_1 l\barνand B->D_2^* l\barν

Exclusive semileptonic decays B->D_1(2420)l\barνand B->D_2^*(2460)l\barνare studied at the subleading order of the heavy quark expansion. The subleading Isgur-Wise functions resulted from the kinetic energy and chromomagnetic corrections to the HQET Lagrangian are calculated by QCD sum rules in the framework of the heavy quark effective theory. The decay rates and branching ratios are computed with the inclusion of the order of 1/m_Q corrections. It is found that the 1/m_Q correction to the decay rate is not large for B->D^*_2 but is very large for B->D_1.

hep-ph

QCD sum rule analysis of the subleading Isgur-Wise form-factor tau_1(v.v') and tau_2(v.v') for B->D_1 l\barνand B->D_2^* l\barν

We present a QCD sum rule calculation of the Isgur-Wise form-factor tau_1(v.v') and tau_2(v.v') for the semileptonic decays B->D_1(2420)l\barνand B->D_2^*(2460)l\barνin the framework of heavy quark effective theory. These two universal functions, associated with the matching of the weak currents in QCD onto those in the effective theory, appear at the order 1/m_Q in the heavy quark expansion of meson weak decay form factors.

hep-ph

Semileptonic B decays into excited charmed mesons from QCD sum rules

Exclusive semileptonic $B$ decays into excited charmed mesons are studied with QCD sum rules in the leading order of heavy quark effective theory. Two universal Isgur-Wise functions τand ζfor semileptonic B decays into four lowest lying excited $D$ mesons ($D_1$, $D_2^*$, $D'_0$, and $D'_1$) are determined. The decay rates and branching ratios for these processes are calculated.

hep-ph

Order (1/m_Q) Corrections to Masses of Excited Heavy Mesons From QCD Sum Rules

The $O(1/m_Q)$ corrections to masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. Numerical results for the matrix elements of the heavy quark kinetic energy operator K and chromomagnetic interaction operator S are obtained for the lowest excited doublets $(0^+, 1^+)$ and $(1^+, 2^+)$.

hep-ph

QCD Sum Rules for Masses of Excited Heavy Mesons

The masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. A set of interpolating currents creating (annihilating) excited heavy mesons with arbitrary spin and parity are proposed and their properties are discussed. Numerical results at the leading order of the {\cal O}(1/m_Q) expansion are obtained for the lowest doublets (0^+, 1^+) and (1^+, 2^+).

hep-ph

QCD Sum Rule Analysis for the Λ_b to Λ_c Semileptonic Decay

The 1/m_c and 1/m_b corrections to the Λ_b to Λ_c semi- leptonic decay are analyzed by QCD sum rules. Within the framework of heavy quark effective theory,the subleading baryonic Isgur-Wise func- tion of Λ_b to Λ_c has been calculated. It is shown that the corrections due to the 1/m Lagrangian insertion are negligibly small. The sizable 1/m_Q effect to the decay lies only in the weak current. The decay spectrum and the branching ratio are given.

hep-ph