﻿ 重夸克展开下B→ηlν的光锥求和规则计算 Light Cone Sum Rule for B→ηlν under Heavy Quark Expansion

Modern Physics
Vol.05 No.01(2015), Article ID:14702,7 pages
10.12677/MP.2015.51002

Light Cone Sum Rule for under Heavy Quark Expansion

Chenliang Ma

School of Mathematics and Physics, University of Science and Technology Beijing, Beijing

Email: lianxingqingjie@163.com

Received: Nov. 20th, 2014; revised: Dec. 28th, 2014; accepted: Jan. 7th, 2015

ABSTRACT

The semileptonic decay is studied. The transition form factor and the branching ratio for this decay are calculated by using the light cone sum rule method within the framework of the heavy quark effective field theory. We adopt both the chiral current and the pseudoscalar current in the correlation functions. The results are compared with those from other approaches and experiments.

Keywords:, Light Cone Sum Rule, Heavy Quark Expansion

Email: lianxingqingjie@163.com

1. 引言

2.跃迁矩阵元和形状因子

(1)

(2)

(3)

(4)

(5)

(6)

3. 光锥求和规则

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

4. 数值分析

(18)

(a) (b)

Figure 1. Variation of wave functions and with respect to the Borel parameter at the momentum transfer when choosing the chiral current. The dashed, solid and dotted curves correspond to the threshold respectively

Figure 2. Variation of form factor with respect to the momentum transfer when choosing the chiral current. The dashed curve is calculated from light cone sum rules for and. The solid curve is the parameterized result

(a) (b)

Figure 3. Variation of wave functions and with respect to the Borel parameter at the momentum transfer when choosing the pseudoscalar current. The dashed, solid and dotted curves correspond to the threshold respectively

Table 1. The values of form factor at, parameters a and b, and the branching ratio. “This work (A)” corresponds to the results from the chiral current, “This work (B)” corresponds to those from the pseudoscalar current

(19)

(20)

(21)

5. 结论

Table 2. The values of form factor at, parameters a and b, and the branching ratio considering the mixing. “This work (A)” corresponds to the results from the chiral current, “This work (B)” corresponds to those from the pseudoscalar current

Light Cone Sum Rule for B→ηlν under Heavy Quark Expansion. 现代物理,01,15-22. doi: 10.12677/MP.2015.51002

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