-
B meson physics is an important and popular area of particle physics because of continuous impetus from experimental and theoretical efforts and pursuits. With the running of the Belle-II and LHCb experiments, an increasing number of B meson events will be accumulated, with an expected goal integrated luminosity of
50 ab−1 by the Belle-II detector at thee+e− SuperKEKB collider [1] and approximately300 fb−1 by the LHCb detector at the future High Luminosity LHC (HL-LHC) hadron collider [2]. More than1011Bu,d mesons are expected to become available at the future CEPC [3] and FCC-ee [4] experiments based on approximately1012Z0 boson decays with a branching ratioB(Z0→bˉb)≈15.12 % [5] and a fragmentation fractionf(b→Bu)≈f(b→Bd)≈41.8 % [6]. With the gradual improvement of data processing technology, besides numerous new and unforeseen phenomena, higher precision measurements of B meson weak decays will be achieved. The experimental study of B meson decays is stepping into a golden age of big data and high precision. Higher requirements have been placed on the accuracy of theoretical calculations for B meson decays, which is the fundamental premise behind rigorous testing of the standard model (SM) of elementary particles, finding a solution to the discrepancies between data and theoretical expectations, and searching for new physics beyond the SM.Owing to an inadequate understanding of the dynamic mechanisms of hadronization and quantum chromodynamics (QCD) behavior at low energy scales, the main uncertainties on various theoretical estimations for B meson decays arise from the hadronic matrix elements (HMEs) describing the transition from the involved quarks to hadrons. The calculation of nonleptonic B meson decays is especially complex because both the initial and final states are hadrons. Additionally, nonleptonic B decay modes are rich, and the study of these is interesting and significant. The measurement of nonleptonic B meson decays has been providing abundant information and various constraints on the SM, for example, the angles and sides of the commonly termed unitarity triangle,
VudV∗ub+VcdV∗cb+VtdV∗tb=0 , arising from the Cabibbo-Kobayashi-Maskawa (CKM) matrix [7, 8]. The method of dealing with HMEs as reasonably and reliably as possible is now a central and urgent issue in the theoretical calculation of nonleptonic B meson decays.Based on the widely used Lepage-Brodsky procedure for exclusive processes with a large momentum transfer between hadrons [9] and the power counting rules in heavy quark limits, several attractive QCD-inspired methods, such as the perturbative QCD (PQCD) approach [10–16], QCD factorization (QCDF) approach [17–26], and soft and collinear effective theory [27–34], have been fully developed to evaluate HMEs for nonleptonic B meson decays, where HMEs are phenomenologically expressed as the convolution integral of the scattering amplitudes at the quark level and wave functions (WFs) (or distribution amplitudes (DAs)) at the hadronic level. The calculation accuracy of HMEs may be improved via the following two aspects together: The first is the scattering amplitudes, and the second is the hadronic WFs or DAs. Owing to the asymptotic freedom of QCD, the scattering amplitudes describing hard interactions among quarks are calculable, in principle, order by order with the perturbative quantum field theory. The higher order radiative corrections to HMEs are necessary and important for approaching the true values, reducing the dependence of theoretical results on the renormalization scale, obtaining strong phases closely related to the
CP violation, verifying models, and perfecting methods. In recent years, the next-to-next-to-leading order (NNLO) corrections to HMEs have become available and have shown a large model sensitivity to the hadronic distribution amplitudes, for example, in Refs. [35–39]. The influences of WFs on HMEs are also significant; however, they have attracted relatively insufficient attention compared with the scattering amplitudes. There are numerous studies on nonleptonic B decays using the PQCD approach, which show that the theoretical uncertainties mainly originate from the parameters of the WFs or DAs, for example, in Refs. [40–55], and the actual contributions from the higher twist (for example, twist-3) DAs to the hadronic transition form factors are as important as those from the leading twist (twist-2) DAs [42–47] and those from the next-to-leading order (NLO) QCD radiative corrections to the scattering amplitudes [41, 46]. It has already been recognized from the numerical perspective that the effects from the higher twist hadronic DAs are considerably large rather than formally power suppressed.In our recent study [41],
B→PP decays were systemically reinvestigated using the PQCD approach by considering contributions from B mesonic subleading twist WFs and the updated DAs of the final pseudoscalar mesons. It was found that the contribution from the B mesonic WFsϕB2 , which are usually paid less attention in calculations, have certain influences over HMEs and branching ratios and are comparable with those from the NLO corrections. In this work, a comprehensive study of the effects of the WFsϕB2 and updated DAs of final states using the PQCD approach is extended to charmlessB→PV decays to match the precision improvement of theoretical and experimental results, where V denotes the groundSU(3) vector mesons. Because of our inadequate understanding of the flavor mixing and possible glueball components, the final states ofη andη′ mesons are not currently considered here, that is,P=π and K.This paper is organized as follows. In Section II, the theoretical framework is briefly described. Definitions of kinematic variables and expressions for the WFs involved are presented in Sections III and IV, respectively. The contributions from different twist WFs to the form factors of
B→PV decays are quantitatively analyzed in Section V. In Section VI, the branching ratios andCP asymmetries of theB→PV decays are reevaluated by taking the B mesonic WFsϕB2 into consideration. We conclude with a summary in Section VII. The decay amplitudes and amplitude building blocks for theB→PV decays are displayed in Appendices A and B, respectively. -
It is widely accepted that charmless nonleptonic
B→PV decays are predominantly induced by heavy b quark weak decays within the SM, that is,b→W∗−+u . There are at least three energy scales, the mass of theW± gauge bosonmW , the mass of the b quarkmb , and the QCD characteristic scaleΛQCD , with the hierarchical relationshipmW≫mb≫ΛQCD and each energy scale corresponding to a different interaction dynamic. Based on the operator product expansion and renormalization group (RG) method, the effective Hamiltonian in charge of charmlessB→PV decays can be factorized by the renormalization scaleμ into three parts, the Wilson coefficientsCi , four-quark operatorsQi , andμ -independent couplings of weak interactions, including the Fermi constantGF≈1.166×10−5GeV−2 [5] and CKM factors, and expressed as [56]Heff=GF√2∑q=d,s{VubV∗uq2∑i=1CiQi−VtbV∗tq10∑j=3CjOj}+h.c.
(1) With the phenomenological Wolfenstein parametrization and up to
O(λ8) , the CKM factors involved are expressed asVubV∗ud=Aλ3(ρ−iη)(1−12λ2−18λ4)+O(λ8),
(2) VtbV∗td=Aλ3+A3λ7(ρ−iη−12)−VubV∗ud+O(λ8),
(3) VubV∗us=Aλ4(ρ−iη)+O(λ8),
(4) VtbV∗ts=−Aλ2(1−12λ2−18λ4)+12A3λ6−VubV∗us+O(λ8),
(5) where A,
λ ,ρ , andη are the Wolfenstein parameters; their latest fitted values can be found in Ref. [5]. The Wilson coefficientsCi summarize physical contributions above the energy scaleμ and are computable using the RG-assisted perturbative theory. Their explicit expressions, including the NLO corrections, can be found in Ref. [56]. The local four-quark operators are defined as follows:Q1=[ˉuαγμ(1−γ5)bα] [ˉqβγμ(1−γ5)uβ],
(6) Q2=[ˉuαγμ(1−γ5)bβ] [ˉqβγμ(1−γ5)uα],
(7) Q3=∑q′[ˉqαγμ(1−γ5)bα] [ˉq′βγμ(1−γ5)q′β],
(8) Q4=∑q′[ˉqαγμ(1−γ5)bβ] [ˉq′βγμ(1−γ5)q′α],
(9) Q5=∑q′[ˉqαγμ(1−γ5)bα] [ˉq′βγμ(1+γ5)q′β],
(10) Q6=∑q′[ˉqαγμ(1−γ5)bβ] [ˉq′βγμ(1+γ5)q′α],
(11) Q7=∑q′32Qq′[ˉqαγμ(1−γ5)bα] [ˉq′βγμ(1+γ5)q′β],
(12) Q8=∑q′32Qq′[ˉqαγμ(1−γ5)bβ] [ˉq′βγμ(1+γ5)q′α],
(13) Q9=∑q′32Qq′[ˉqαγμ(1−γ5)bα] [ˉq′βγμ(1−γ5)q′β],
(14) Q10=∑q′32Qq′[ˉqαγμ(1−γ5)bβ] [ˉq′βγμ(1−γ5)q′α],
(15) where
α andβ are the color indices,q′∈ {u , d, c, s,b} , andQq′ is the electric charge of quarkq′ in the unit of|e| . The physical contributions below the energy scaleμ are contained in the HMEs⟨Qi⟩=⟨PV|Qi|B⟩ , which are the focus of the current theoretical calculation.The various treatments on HMEs depend on the different phenomenological approaches corresponding to the understanding of the perturbative and nonperturbative contributions. The joint effort of the transverse momentum for quarks and the Sudakov factors for all participant WFs is considered within the PQCD approach to settle the soft endpoint contributions from the collinear approximation. The master formula for HMEs with the PQCD approach is generally written as
⟨PV|Qi|B⟩∝∫dx1dx2dx3db1db2db3Hi(ti,x1,b1,x2,b2,x3,b3)×ΦB(x1,b1)e−SBΦP(x2,b2)e−SPΦV(x3,b3)e−SV,
(16) where
bi is the conjugate variable of the transverse momentum→ki⊥ of the valence quarks,Hi is the scattering amplitudes for hard gluon exchange interactions among quarks, ande−Si is the Sudakov factor. Other variables and inputs are described below. -
It is usually assumed that in the heavy quark limit, light quarks rapidly move away from the b quark decaying point at near the speed of light. Moreover, light cone variables are generally used in expressions. The relations between the four-dimensional space-time coordinates
xμ= (x0 ,x1 ,x2 ,x3 )= (t, x, y, z) and the light-cone coordinatesxμ= (x+ ,x− ,→x⊥ ) are defined asx±=(x0±x3)/√2 and→x⊥= (x1 ,x2 ). The light cone planes correspond tox±=0 . The scalar product of any two vectors is given bya⋅b=aμbμ=a+b−+a−b+−→a⊥⋅→b⊥ .In the rest frame of the B meson, the light cone kinematic variables are defined as
pB=p1=mB√2(1,1,0),
(17) pP=p2=mB√2(0,1−r2V,0),
(18) pV=p3=mB√2(1,r2V,0),
(19) e∥V=pVmV−mVpV⋅n−n−,
(20) k1=x1p1+(0,0,→k1⊥),
(21) k2=mB√2(0,x2,→k2⊥),
(22) k3=mB√2(x3,0,→k3⊥),
(23) where the mass ratio
rV=mV/mB ,e∥V is the longitudinal polarization vector, and the variablesx1 and→k1⊥ are the longitudinal momentum fraction and transverse momentum of the light quark in the B meson, respectively. The variablesxi and→ki⊥ fori=2 and3 are the longitudinal momentum fractions and transverse momentum of the antiquarks in the final pseudoscalar and vector mesons, respectively. -
B mesonic WFs are generally defined as [41–43, 57, 58]
⟨0|ˉqα(z)bβ(0)|¯B(p1)⟩=+i4fB∫d4ke−ik1⋅z{(⧸p1+mB)γ5[⧸n−√2ϕ+B+⧸n+√2ϕ−B]}βα=−i4fB∫d4ke−ik1⋅z{(⧸p1+mB)γ5[ϕ++⧸n+√2(ϕ+B−ϕ−B)]}βα=−i4fB∫d4ke−ik1⋅z{(⧸p1+mB)γ5(ϕB1+⧸n+√2ϕB2)}βα,
(24) where
fB is the decay constant. The coordinate z of the light quark and the vectorsn+= (1 ,0 ,→0 ) andn−= (0 ,1 ,→0 ) are on the light cone, that is,z2=0 andn2±=0 . The scalar functionsϕ+B andϕ−B are the leading and subleading twist WFs, respectively.ϕ+B andϕ−B have different asymptotic behaviors as the longitudinal momentum fraction of the light quarkx1→0 . Their relations areϕ+B(x1)+x1ϕ−′B(x1)=0,
(25) ϕB1=ϕ+B,
(26) ϕB2=ϕ+B−ϕ−B.
(27) Although the expressions of
ϕ+B are generally different from those ofϕ−B with the equation of motion Eq. (25), an approximation ofϕ+B=ϕ−B is often used in phenomenological studies of nonleptonic B meson decays, that is, only contributions fromϕB1 are considered, and those fromϕB2 are absent. However, it has been shown in Refs. [40–46] thatϕB2 is necessary to HMEs rather than a negligible factor, and its contributions to the form factorsFB→π0 with the PQCD approach can even reach up to30 % in certain cases [42, 43]. Additionally, its share of the branching ratio could be as large as those from NLO corrections [41]. The possible influence ofϕB2 onB→PV decays with the PQCD approach is a focus of this paper. One candidate for the most commonly used leading B mesonic WFsϕ+B in actual calculations with the PQCD approach is expressed as [14]ϕ+B(x1,b1)=Nx21ˉx21exp{−(x1mB√2ωB)2−12ω2Bb21},
(28) and the corresponding B mesonic WFs
ϕ−B is written as [41, 42]ϕ−B(x1,b1)=N2ω4Bm4Bexp(−12ω2Bb21){√πmB√2ωB×Erf(mB√2ωB,x1mB√2ωB)+[1+(mBˉx1√2ωB)2]exp[−(x1mB√2ωB)2]−exp(−m2B2ω2B)},
(29) where
ωB is the shape parameter, andˉx1=1−x1 . The normalization constant N is determined by∫10dx1ϕ±B(x1,0)=1.
(30) The WFs of the final states including the light pseudoscalar mesons and longitudinally polarized vector mesons are respectively defined as [59–62]
⟨P(p2)|ˉqi(0)qj(z)|0⟩=−ifP4∫10dx2e+ik2⋅z{γ5[⧸p2ϕaP+μPϕpP−μP(⧸n−⧸n+−1)ϕtP]}ji,
(31) ⟨V(p3,e∥)|ˉqi(0)qj(z)|0⟩=14∫10dx3e+ik3⋅z{⧸e∥mVf∥VϕvV+⧸e∥⧸p3f⊥VϕtV−mVf⊥VϕsV}ji,
(32) where
fP ,f∥V , andf⊥V are the decay constants,ϕaP andϕvV are the twist-2 WFs, andϕp,tP andϕt,sV are the twist-3 WFs. It has been previously shown that the numerical values of the form factorFB→π0,1 were highly dependent on the models for pionic WFs [42, 44–46], and the contributions from the twist-3 pionic DAs toFB→π0,1 were larger than those from twist-2 pionic DAs [42, 45, 46]. According to the convention of Refs. [61, 62], and taking the pseudoscalarP=K meson and vectorV=K∗ meson as an example, their DAs are written asϕaK(x)=6xˉx{1+aK1C3/21(ξ)+aK2C3/22(ξ)},
(33) ϕpK(x)=1+3ρK+−9ρK−aK1+18ρK+aK2+32(ρK++ρK−)(1−3aK1+6aK2)ln(x)+32(ρK+−ρK−)(1+3aK1+6aK2)ln(ˉx)−(32ρK−−272ρK+aK1+27ρK−aK2)C1/21(ξ)+(30ηK−3ρK−aK1+15ρK+aK2)C1/22(ξ),
(34) ϕtK(x)=32(ρK−−3ρK+aK1+6ρK−aK2)−C1/21(ξ){1+3ρK+−12ρK−aK1+24ρK+aK2+32(ρK++ρK−)(1−3aK1+6aK2)ln(x)+32(ρK+−ρK−)(1+3aK1+6aK2)ln(ˉx)}−3(3ρK+aK1−152ρK−aK2)C1/22(ξ),
(35) ϕvK∗(x)=6xˉx{1+a∥,K∗1C3/21(ξ)+a∥,K∗2C3/22(ξ)},
(36) ϕtK∗(x)=3ξ{C1/21(ξ)+a⊥,K∗1C1/22(ξ)+a⊥,K∗2C1/23(ξ)}+32ms+mqmK∗f∥K∗f⊥K∗{1+8ξa∥,K∗1+(21−90xˉx)a∥,K∗2+ξlnˉx(1+3a∥,K∗1+6a∥,K∗2)−ξlnx(1−3a∥,K∗1+6a∥,K∗2)}−32ms−mqmK∗f∥K∗f⊥K∗ξ{2+9ξa∥,K∗1+(22−60xˉx)a∥,K∗2+lnˉx(1+3a∥,K∗1+6a∥,K∗2)+lnx(1−3a∥,K∗1+6a∥,K∗2)},
(37) ϕsK∗(x)=−3C1/21(ξ)−3C1/22(ξ)a⊥,K∗1−3C1/23(ξ)a⊥,K∗2−32ms+mqmK∗f∥K∗f⊥K∗{C1/21(ξ)+2C1/22(ξ)a∥,K∗1+[3C1/23(ξ)+18C1/21(ξ)]a∥,K∗2+(lnˉx+1)(1+3a∥,K∗1+6a∥,K∗2)−(lnx+1)(1−3a∥,K∗1+6a∥,K∗2)}+32ms−mqmK∗f∥K∗f⊥K∗{9C1/21(ξ)a∥,K∗1+10C1/22(ξ)a∥,K∗2+(lnˉx+1)(1+3a∥,K∗1+6a∥,K∗2)+(lnx+1)(1−3a∥,K∗1+6a∥,K∗2)},
(38) where x is the longitudinal momentum fraction of the strange quark, and
ξ=x−ˉx=2x−1 .Cmn is the Gegenbauer polynomials.aKn ,a∥,K∗n , anda⊥,K∗n are the Gegenbauer moments. The dimensionless parametersρK+=(ms+mq)2/m2K andρK−=(m2s−m2q)/m2K [61].The shape lines of mesonic DAs with the inputs in Table 1 are displayed in Fig. 1. From this, the following is clear: (1) The nonzero distributions of
ϕ±B are mainly located in the small x regions, andϕ±B vanishes asx→1 . This fact is consistent with the intuitive expectation that the light quark shares a small longitudinal momentum fraction in the B meson. (2) The shape lines ofϕ−B differ from those ofϕ+B in the small x regions. It is particularly noticeable that the DAsϕ−B andϕ+B exhibit different endpoint behaviors atx=0 . Thus, it is clear thatϕB2=ϕ+B−ϕ−B≠0 , and the approximationϕB2=0 in previous studies might be inappropriate and insufficient. (3) The integral∫dxϕ−Bx will appear in the scattering amplitudes, for example, the form factors for the transition from the B meson to final hadrons. The value ofϕ−B increases with a decrease in x, which implies that the integrals∫dxϕ−Bx and∫dxϕB2x may be significant in the small x regions. The potential contributions from the subleading DAsϕ−B could be greatly enhanced when x approaches zero and should be given due consideration in the calculation. (4) The values ofϕ−B andϕB2 are nonzero at the endpointx=0 ; therefore, the integral∫dxϕB2x will be infrared divergent at the endpoint with the collinear approximation. This fact indicates that it may be reasonable and necessary for the PQCD approach to conciliate the nonperturbative contributions by considering the effects of the transverse momentum of valence quarks and the Sudakov factors. (5) The distributions ofϕ±B are sensitive to the shape parameterωB . The larger the value ofωB , the wider distributions ofϕ±B . The theoretical results with the PQCD approach will depend on the choice ofωB . (6) The expressions for the DAsϕa,p,tP andϕv,t,sV are different from their asymptotic forms. With respect to the exchangex↔ˉx , the DAsϕa,pπ andϕv,tρ,ϕ,ω are entirely symmetric, and the twist-3 DAsϕtπ andϕsρ,ϕ,ω are entirely antisymmetric, whereas the kaonic DAsϕa,p,tK andϕv,t,sK∗ are asymmetric.Wolfenstein parameters of the CKM matrix [5] A=0.790+0.017−0.012 λ=0.22650±0.00048 ˉρ=0.141+0.016−0.017 ˉη=0.357±0.011 mass of particle (in the unit of MeV) [5] mπ±=139.57 mK±=493.677±0.016 mρ=775.26±0.25 mK∗±=895.5±0.8 mπ0=134.98 mK0=497.611±0.013 mω=782.65±0.12 mK∗0=895.55±0.20 mBu=5279.34±0.12 mBd=5279.65±0.12 mϕ=1019.461±0.016 decay constants (in the unit of MeV) f∥ρ=216±3 [62]f∥ω=187±5 [62]f∥ϕ=215±5 [62]f∥K∗=220±5 [62]f⊥ρ=165±9 [62]f⊥ω=151±9 [62]f⊥ϕ=186±9 [62]f⊥K∗=185±10 [62]fB=190.0±1.3 [5]fπ=130.2±1.2 [5]fK=155.7±0.3 [5]Gegenbauer moments on the scale of μ=1 GeV [61, 62]a∥,ρ,ω2=0.15±0.07 a∥,ϕ2=0.18±0.08 a∥,K∗1=0.03±0.02 a∥,K∗2=0.11±0.09 a⊥,ρ,ω2=0.14±0.06 a⊥,ϕ2=0.14±0.07 a⊥,K∗1=0.04±0.03 a⊥,K∗2=0.10±0.08 aπ,ρ,ω,ϕ1=0 aπ2=0.25±0.15 aK1=0.06±0.03 aK2=0.25±0.15 Table 1. Values of input parameters, where their central values are regarded as the default inputs unless otherwise specified.
-
As far as we know, the implications of hadronic WFs on transition form factors have been carefully studied with the PQCD approach in Refs. [40–47], where HMEs for the transition form factors are expressed as the convolution integral of the scattering amplitudes and WFs of the initial and final mesons, and the lowest order approximation of the scattering amplitudes is illustrated with the one-gluon-exchange diagrams in Fig. 2.
Figure 2. (color online) Diagrams contributing to the
¯B→P V transition with the PQCD approach, where the dots denote an appropriate diquark current interaction, and the dashed boxes represent the scattering amplitudes.It is well known that the two form factors,
F1(q2) andA0(q2) corresponding to the vector and axial-vector currents of the weak interactions, respectively, are directly related toB→PV decays. The detailed definitions and explicit expressions of form factors can be found in Ref. [43], where the contributions from the higher twist DAs are considered properly. The dependences of form factors on certain input parameters are shown in Fig. 3. It is clearly shown in Fig. 3 that (1) the form factorsF1 andA0 are highly sensitive to the shape parameterωB of B mesonic WFs and the contributions fromϕB2 . In general, the values of the form factorsF1 andA0 decrease with increasingωB . This type of regular phenomenon has also been found in previous studies [40–42, 44, 45, 48]. (2) In addition, the form factorF1 is also dependent on the value of the chiral parameterμP . For a more comprehensive analysis, the numerical results of the form factors with specific inputs are listed in Table 2. It is clear from Table 2 that (1) when the contributions fromϕB2 are not considered, the total share of the form factorF1 from the twist-3 DAsϕp,tP of the recoiled light pseudoscalar meson far outweighs those from the leading twist DAsϕaP and account for more than60 %. The total share of the form factorA0 from the twist-3 DAsϕt,sV of the recoiled vector meson, which is approximately60 %, far exceeds those from the twist-2 DAsϕvV . (2) When only the contributions from the twist-2 DAsϕaP andϕvV are considered, the share of the form factorsF1 andA0 from the B mesonic WFsϕB2 is approximately40 %. (3) When the contributions from both the twist-2 and twist-3 DAsϕa,p,tP andϕv,t,sV are considered, the share of the form factorsF1 andA0 from the B mesonic WFsϕB2 is approximately20 %. The contributions fromϕB2 to the form factors have been investigated in previous studies [40–46]. The general consensus seems to be that the unnegligible contributions fromϕB2 to the form factors should be given due attention. Here, we would like to note that for arguments on the reliability of the perturbative calculation of the form factors using the PQCD approach, which is not the focus of this study, one can refer to detailed analyses, for example, in Refs. [43–45].FB→π1(0) ϕaπ ϕpπ ϕtπ Σπ ϕaπ/Σπ ϕpπ/Σπ ϕtπ/Σπ ϕB1 0.064 0.106 0.019 0.188 34.0 56.0 9.9 ϕB2 0.045 −0.003 −0.000 0.042 107.5 −6.8 −0.7 ΣB 0.109 0.103 0.018 0.230 47.4 44.7 8.0 ϕB2/ΣB 41.1 −2.8 −1.6 18.1 FB→K1(0) ϕaK ϕpK ϕtK ΣK ϕaK/ΣK ϕpK/ΣK ϕtK/ΣK ϕB1 0.081 0.131 0.018 0.230 35.3 56.9 7.8 ϕB2 0.056 −0.004 −0.000 0.053 107.3 −6.9 −0.5 ΣB 0.138 0.127 0.018 0.282 48.7 45.0 6.3 ϕB2/ΣB 41.0 −2.8 −1.4 18.6 AB→ρ0(0) ϕvρ ϕtρ ϕsρ Σρ ϕvρ/Σρ ϕtρ/Σρ ϕsρ/Σρ ϕB1 0.097 0.090 0.044 0.231 41.8 39.1 19.1 ϕB2 0.069 −0.002 −0.001 0.067 103.6 −2.7 −0.9 ΣB 0.166 0.088 0.044 0.298 55.7 29.7 14.6 ϕB2/ΣB 41.8 −2.0 −1.4 22.4 AB→K∗0(0) ϕvK∗ ϕtK∗ ϕsK∗ ΣK∗ ϕvK∗/ΣK∗ ϕtK∗/ΣK∗ ϕsK∗/ΣK∗ ϕB1 0.098 0.106 0.052 0.256 38.1 41.4 20.5 ϕB2 0.070 −0.003 −0.001 0.067 104.5 −3.7 −0.8 ΣB 0.168 0.104 0.052 0.323 52.0 32.0 16.0 ϕB2/ΣB 42.0 −2.4 −1.1 20.9 Table 2. Contributions from different twist hadronic DAs to the form factors
F1(q2) andA0(q2) atq2=0 using the PQCD approach, whereωB=0.4 GeV,μP=1.4 GeV,ΣP=ϕaP+ϕpP+ϕtP ,ΣV=ϕvV+ϕtV+ϕsV , andΣB=ϕB1+ϕB2 . The ratioϕi/Σj is expressed as a percentage. -
According to the above analysis, it is clear that the contributions from higher twist DAs are important to HMEs for nonleptonic B decays using the PQCD approach. In most phenomenological studies of
B→PV decays with the PQCD approach, the shares of both the twist-2 DAs (ϕaP andϕvV ) and twist-3 DAs (ϕp,tP andϕt,sV ) for the final mesons have been carefully and commonly considered, such as in Refs. [48–55]. In contrast, the possible influence of the B mesonic WFsϕ−B orϕB2 on nonleptonic B decays garners significantly less attention. In this paper, our main purpose is to investigate the effects of the B mesonic WFsϕB2 onB→PV decays using the PQCD approach.Leading order Feynman diagrams are shown in Fig. 4. The analytical expressions of each subdiagram amplitude are listed in Appendix B. It is clearly seen that (1) for the factorizable annihilation diagrams (e) and (f), the initial B meson is completely disconnected from the final state
PV system, where the disconnected B meson corresponds to its decay constant and should have nothing to do with its WFsϕB2 . These arguments are fully verified by Eqs. (B31)–(B42). (2) For the emission diagrams (a-d) and the nonfactorizable annihilation diagrams (g-h), the B meson always connects with either one or two of the final states via one-gluon-exchange interactions. Therefore, these corresponding amplitudes would generally be affected by the B mesonic WFsϕB2 and should be updated accordingly.Figure 4. (color online) Feynman diagrams contributing to
¯B→PV decays with the PQCD approach, whereM1,2=P and V, the dots denote appropriate interactions, and the dashed circles represent the scattering amplitudes. (a) and (b) are factorizable emission diagrams. (c) and (d) are nonfactorizable emission diagrams. (e) and (f) are factorizable annihilation diagrams. (g) and (h) are nonfactorizable annihilation diagrams.The decay amplitudes for
B→PV decays with the PQCD approach are expressed as the sum of a series of multidimensional convolutions,A(B→PV)=⟨PV|Heff|B⟩=GF√2∑iFi∫dx1dx2dx3db1db2db3×Ti(ti,x1,b1,x2,b2,x3,b3)×Ci(ti)ΦB(x1,b1)e−SB×ΦP(x2,b2)e−SPΦV(x3,b3)e−SV,
(39) where
Fi is the CKM factor, and the rescattering functionsTi are represented by the dashed circles in Fig. 4. The calculation expressions for theB→PV decays are listed in detail in Appendix A.In the rest frame of the B meson, the
CP -averaged branching ratios are defined asB=τB16πpcmm2B{|A(B→f)|2+|A(¯B→ˉf)|2},
(40) where
τB is the lifetime of the B meson,τBu=1.638(4) ps, andτBd=1.519(4) ps [5].pcm is the common center-of-mass momentum of final states.For charged
Bu meson decays, directCP violating asymmetry arising from interferences among different amplitudes is defined asACP=Γ(B−→f)−Γ(B+→ˉf)Γ(B−→f)+Γ(B+→ˉf)=|A(B−→f)|2−|A(B+→ˉf)|2|A(B−→f)|2+|A(B+→ˉf)|2.
(41) For neutral
Bd meson decays, the effects ofB0 -¯B0 mixing should be considered. Time-dependentCP violating asymmetry is defined asACP(t)=Γ(¯B0(t)→f)−Γ(B0(t)→ˉf)Γ(¯B0(t)→f)+Γ(B0(t)→ˉf).
(42) CP violating asymmetries can, in principle, be divided into three cases according to the final states [5, 63, 64]. For the sake of simplification, the following conventional symbols will be defined and used:Af=A(B0(0)→f),ˉAf=A(¯B0(0)→f),
(43) Aˉf=A(B0(0)→ˉf),ˉAˉf=A(¯B0(0)→ˉf).
(44) ● Case 1: The final states originate from either
B0 decays or¯B0 decays, but not both, that is,¯B0→f andB0→ˉf withf≠ˉf , for example, the¯B0→π+K∗− decay. TheCP asymmetries are immune toB0 -¯B0 mixing and have a similar definition to the directCP asymmetry in Eq. (41).● Case 2: The final states are the eigenstates of the
CP transformation, that is,fCP=ηfˉf with the eigenvalue|ηf|=1 . The final states can originate from bothB0 decays and¯B0 decays, that is,¯B0→f←B0 , for example, the¯B0→π0ρ0 decay.For
B0 -¯B0 mixing, the SM predicts that the ratio of the decay width differenceΔΓ of mass eigenstates to the total decay widthΓ is small, that is,ΔΓ/Γ=0.001±0.010 , from data [5]. In the most general calculation, it is usually assumed thatΔΓ=0 ; thus, theCP asymmetries can be expressed as [5]ACP(t)=Sfsin(Δmt)−Cfcos(Δmt),
(45) Sf=2Im(λf)1+|λf|2,Cf=1−|λf|21+|λf|2,λf=qpˉAfAf,
(46) where
q/p=V∗tbVtd/VtbV∗td describesB0 -¯B0 mixing. Sometimes, time-integratedCP asymmetries are written asACP=∫∞0dtΓ(¯B0(t)→f)−∫∞0dtΓ(B0(t)→ˉf)∫∞0dtΓ(¯B0(t)→f)+∫∞0dtΓ(B0(t)→ˉf)
(47) =x1+x2Sf−11+x2Cf,
(48) with
x=Δm/Γ=0.769(4) [5] for theB0 -¯B0 system, whereΔm=0.5065(19)ps−1 [5] is the mass difference of the mass eigenstates.● Case 3: The final states are not the eigenstates of the
CP transformation; however, both f andˉf are the common final states of¯B0 andB0 , that is,¯B0→ (f &ˉf )←B0 , for example, the¯B0→π+ρ− andπ−ρ+ decays.The four time-dependent partial decay widths can be expressed as [63, 64]
Γ(B0(t)→f)=12e−Γt(|Af|2+|ˉAf|2)×{1+aϵ′cos(Δmt)+aϵ+ϵ′sin(Δmt)},
(49) Γ(B0(t)→ˉf)=12e−Γt(|ˉAˉf|2+|Aˉf|2)×{1+ˉaϵ′cos(Δmt)+ˉaϵ+ϵ′sin(Δmt)},
(50) Γ(¯B0(t)→f)=12e−Γt(|Af|2+|ˉAf|2)×{1−aϵ′cos(Δmt)−aϵ+ϵ′sin(Δmt)},
(51) Γ(¯B0(t)→ˉf)=12e−Γt(|ˉAˉf|2+|Aˉf|2)×{1−ˉaϵ′cos(Δmt)−ˉaϵ+ϵ′sin(Δmt)},
(52) with the following definitions:
aϵ′=1−|λf|21+|λf|2,aϵ+ϵ′=−2Im(λf)1+|λf|2,λf=V∗tbVtdVtbV∗tdˉAfAf,
(53) ˉaϵ′=1−|ˉλf|21+|ˉλf|2,ˉaϵ+ϵ′=−2Im(ˉλf)1+|ˉλf|2,ˉλf=V∗tbVtdVtbV∗tdˉAˉfAˉf.
(54) Besides
ACP in Eq.(48),CP asymmetries can also be expressed by the physical quantitiesaϵ′ ,aϵ+ϵ′ ,ˉaϵ′ , andˉaϵ+ϵ′ .According to the previous analysis of the form factors in Fig. 3, it is natural to suppose that the theoretical results of the branching ratios would be strongly dependent on the shape parameter
ωB . In this paper, we optimize the parameterωB using the minimumχ2 method:χ2=∑iχ2i=∑i(Bth.i−Bexp.i)2σ2i,
(55) where
Bth.i andBexp.i denote the theoretical results and experimental data on the branching ratio, respectively.σi denotes the errors on the experimental measurements. The distribution ofχ2 vs the shape parameterωB is shown in Fig. 5, where the contributions from the B mesonic WFsϕB2 are considered. Three optimal scenarios of the shape parameterωB corresponding to experimental data from the PDG, BaBar, and Belle groups are obtained with the chiral massμP=1.4 GeV, that is,Figure 5. (color online) Distribution of
χ2 vs the shape parameterωB , where the red points at the arrowheads correspond to the optimal values.● Scenario 1 (S1):
ωB=0.46 GeV from PDG data withχ2min. /dof≈519/18≈29 ,● Scenario 2 (S2):
ωB=0.49 GeV from BaBar data withχ2min. /dof≈238/16≈15 ,● Scenario 3 (S3):
ωB=0.43 GeV from Belle data withχ2min. /dof≈141/13≈11 .As is well known, the errors of the PDG group from a weighted average of selected data are generally smaller than those of any independent experimental groups. Therefore, it is clear from Eq. (55) that the relatively smaller (larger) errors on the PDG (Belle) data result in the relatively larger (smaller) value of
χ2min. /dof.The numerical results of the
CP -averaged branching ratios for three scenarios (S1, S2, and S3) using the PQCD approach with experimental data are presented in Tables 3 and 4, and the previous PQCD results without contributions from the B mesonic WFsϕB2 are listed in Table 5. To obtain a clear and comprehensive impression of the agreement between the theoretical and experimental results, theχ2i distributions are illustrated in Fig. 6. The results of theCP asymmetries are presented in Tables 6, 7, and 8. It should be noted that the uncertainties on our results only originate from the parametersωB andμP based on the previous analysis of form factors. Uncertainties from other factors, such as the Gegenbauer moments① and different models of the mesonic WFs, are not carefully scrutinized here, but deserve a more dedicated study.mode B−→π−ρ0 B−→π0ρ− B−→π−ω B−→π−ϕ data PDG 8.3±1.2 10.9±1.4 6.9±0.5 (3.2±1.5)×10−2 S1 ϕB1 +ϕB2 4.25+0.22+0.01−0.21−0.00 6.91+0.39+0.46−0.37−0.45 3.83+0.20+0.01−0.19−0.01 4.9+0.4+0.6−0.4−0.5×10−2 ϕB1 2.66+0.15+0.01−0.14−0.01 4.56+0.28+0.38−0.26−0.36 2.47+0.14+0.01−0.13−0.01 4.2+0.3+0.5−0.3−0.5×10−2 data BaBar 8.1±1.7 10.2±1.7 6.7±0.6 S2 ϕB1 +ϕB2 3.66+0.19+0.01−0.18−0.00 5.87+0.32+0.38−0.30−0.37 3.28+0.17+0.01−0.16−0.01 3.9+0.3+0.4−0.3−0.4×10−2 ϕB1 2.26+0.12+0.01−0.12−0.01 3.83+0.22+0.31−0.21−0.30 2.10+0.12+0.00−0.11−0.00 3.3+0.3+0.4−0.3−0.4×10−2 data Belle 8.0±2.4 13.2±3.0 6.9±0.8 S3 ϕB1 +ϕB2 4.96+0.26+0.01−0.25−0.00 8.17+0.48+0.56−0.45−0.54 4.47+0.24+0.01−0.23−0.01 6.2+0.5+0.7−0.5−0.7×10−2 ϕB1 3.13+0.18+0.01−0.17−0.01 5.45+0.34+0.46−0.32−0.44 2.91+0.17+0.01−0.16−0.01 5.3+0.4+0.6−0.4−0.6×10−2 mode B−→K−K∗0 B−→K0K∗− B−→π0K∗− B−→K−ρ0 data PDG 0.59±0.08 6.8±0.9 3.7±0.5 S1 ϕB1 +ϕB2 0.35+0.02+0.05−0.02−0.05 4.7+0.1+1.3−0.1−0.8×10−2 2.90+0.19+0.22−0.18−0.22 1.04+0.01+0.03−0.01−0.00 ϕB1 0.24+0.02+0.04−0.01−0.04 4.8+0.1+1.3−0.1−1.0×10−2 1.96+0.14+0.19−0.13−0.18 0.88+0.01+0.03−0.01−0.01 data BaBar 6.4±1.0 3.56±0.73 S2 ϕB1 +ϕB2 0.29+0.02+0.04−0.02−0.04 4.4+0.1+1.0−0.1−0.7×10−2 2.40+0.15+0.18−0.14−0.18 1.01+0.01+0.02−0.01−0.00 ϕB1 0.19+0.01+0.03−0.01−0.03 4.5+0.1+1.1−0.1−0.8×10−2 1.61+0.11+0.15−0.10−0.15 0.86+0.01+0.02−0.01−0.01 data Belle 3.89±0.64 S3 ϕB1 +ϕB2 0.42+0.03+0.06−0.03−0.06 5.1+0.2+1.6−0.1−1.0×10−2 3.52+0.24+0.27−0.22−0.26 1.08+0.02+0.03−0.01−0.00 ϕB1 0.29+0.02+0.05−0.02−0.05 5.3+0.2+1.6−0.2−1.2×10−2 2.41+0.18+0.23−0.16−0.22 0.91+0.01+0.03−0.01−0.01 mode B−→K−ω B−→π−¯K∗0 B−→¯K0ρ− B−→K−ϕ data PDG 6.5±0.4 10.1±0.8 7.3±1.2 8.8±0.7 S1 ϕB1 +ϕB2 3.43+0.17+0.26−0.16−0.30 4.44+0.31+0.44−0.28−0.42 1.36+0.00+0.12−0.00−0.05 13.48+0.96+2.32−0.89−2.27 ϕB1 2.76+0.13+0.28−0.12−0.30 3.04+0.22+0.36−0.20−0.34 1.36+0.01+0.15−0.01−0.09 9.50+0.73+1.94−0.67−1.87 data BaBar 6.3±0.6 10.1±2.0 6.5±2.2 9.2±0.8 S2 ϕB1 +ϕB2 2.99+0.14+0.22−0.13−0.25 3.65+0.24+0.36−0.23−0.34 1.36+0.00+0.10−0.00−0.04 11.00+0.77+1.87−0.71−1.83 ϕB1 2.41+0.11+0.23−0.10−0.25 2.48+0.17+0.29−0.16−0.28 1.34+0.00+0.12−0.00−0.07 7.64+0.57+1.55−0.53−1.49 data Belle 6.8±0.6 9.67±1.10 9.60±1.40 S3 ϕB1 +ϕB2 3.98+0.21+0.32−0.19−0.36 5.44+0.39+0.53−0.36−0.51 1.38+0.01+0.16−0.01−0.07 16.60+1.21+2.89−1.12−2.83 ϕB1 3.19+0.16+0.33−0.15−0.36 3.76+0.29+0.44−0.26−0.42 1.38+0.01+0.18−0.01−0.11 11.88+0.93+2.43−0.86−2.35 Table 3.
CP -averaged branching ratios (in the unit of10−6 ) forBu→PV decays. The central theoretical values are calculated with three scenario parameters ofωB to compare with data from the PDG, BaBar, and Belle groups [5]. The first theoretical uncertainties arise from variations inωB=0.46±0.01 GeV for S1,ωB=0.49±0.01 GeV for S2, andωB=0.43±0.01 GeV for S3. The second theoretical uncertainties originate from variations inμP=1.4±0.1 GeV.mode ¯B0→π+ρ− ¯B0→π−ρ+ ¯B0→π0ω ¯B0→π0ρ0 ¯B0→π0ϕ data PDG 23.0±2.3 <0.5 2.0±0.5 <0.15 S1 ϕB1 +ϕB2 10.11+0.59+0.60−0.55−0.59 7.52+0.41+0.14−0.38−0.13 0.16+0.01+0.00−0.01−0.00 7.0+0.3+0.4−0.3−0.3×10−2 2.3+0.2+0.3−0.2−0.2×10−2 ϕB1 6.35+0.40+0.49−0.37−0.47 4.58+0.26+0.12−0.25−0.11 0.12+0.01+0.00−0.01−0.00 5.8+0.3+0.2−0.3−0.1×10−2 2.0+0.2+0.2−0.2−0.2×10−2 data BaBar 22.6±2.8 <0.5 1.4±0.7 <0.28 S2 ϕB1 +ϕB2 8.56+0.48+0.50−0.45−0.49 6.44+0.34+0.12−0.32−0.11 0.13+0.01+0.00−0.01−0.00 6.2+0.3+0.3−0.2−0.3×10−2 1.8+0.1+0.2−0.1−0.2×10−2 ϕB1 5.32+0.32+0.41−0.30−0.39 3.88+0.22+0.10−0.20−0.09 0.10+0.01+0.00−0.01−0.00 5.1+0.2+0.1−0.2−0.1×10−2 1.5+0.1+0.2−0.1−0.2×10−2 data Belle 22.6±4.5 <2.0 3.0±0.9 <0.15 S3 ϕB1 +ϕB2 11.99+0.72+0.73−0.67−0.71 8.82+0.49+0.17−0.46−0.16 0.19+0.01+0.01−0.01−0.01 8.0+0.4+0.4−0.3−0.4×10−2 2.9+0.2+0.3−0.2−0.3×10−2 ϕB1 7.64+0.49+0.60−0.46−0.58 5.43+0.32+0.14−0.30−0.14 0.14+0.01+0.01−0.01−0.01 6.7+0.3+0.2−0.3−0.2×10−2 2.5+0.2+0.3−0.2−0.3×10−2 mode ¯B0→¯K0K∗0 ¯B0→K0¯K∗0 ¯B0→π+K∗− ¯B0→K−ρ+ ¯B0→π0¯K∗0 data PDG <0.96 7.5±0.4 7.0±0.9 3.3±0.6 S1 ϕB1 +ϕB2 0.23+0.02+0.04−0.02−0.03 0.16+0.01+0.02−0.01−0.02 3.61+0.24+0.34−0.22−0.33 1.80+0.04+0.19−0.03−0.13 1.30+0.09+0.16−0.08−0.15 ϕB1 0.15+0.01+0.03−0.01−0.03 0.12+0.01+0.02−0.00−0.02 2.53+0.17+0.29−0.16−0.27 1.58+0.03+0.19−0.03−0.14 0.94+0.07+0.13−0.06−0.13 data BaBar <1.9 8.0±1.4 6.6±0.9 3.3±0.6 S2 ϕB1 +ϕB2 0.19+0.01+0.03−0.01−0.03 0.14+0.01+0.02−0.01−0.01 2.99+0.19+0.29−0.18−0.27 1.71+0.03+0.16−0.03−0.10 1.07+0.07+0.13−0.06−0.13 ϕB1 0.12+0.01+0.02−0.01−0.02 0.11+0.00+0.02−0.00−0.01 2.09+0.13+0.24−0.12−0.23 1.51+0.02+0.15−0.02−0.11 0.77+0.05+0.11−0.05−0.10 data Belle 8.4±1.5 15.1±4.2 S3 ϕB1 +ϕB2 0.28+0.02+0.04−0.02−0.04 0.18+0.01+0.02−0.01−0.02 4.40+0.30+0.42−0.28−0.40 1.93+0.05+0.24−0.05−0.16 1.60+0.12+0.20−0.11−0.19 ϕB1 0.19+0.01+0.04−0.01−0.03 0.14+0.01+0.02−0.01−0.02 3.10+0.23+0.35−0.21−0.34 1.68+0.04+0.23−0.04−0.17 1.15+0.09+0.17−0.08−0.16 mode ¯B0→¯K0ρ0 ¯B0→¯K0ω ¯B0→¯K0ϕ ¯B0→K+K∗− ¯B0→K−K∗+ data PDG 3.4±1.1 4.8±0.4 7.3±0.7 <0.4 S1 ϕB1 +ϕB2 0.81+0.02+0.18−0.02−0.14 3.54+0.17+0.27−0.16−0.31 12.31+0.88+2.15−0.81−2.11 5.1+0.1+0.0−0.1−0.0×10−2 2.6+0.1+0.1−0.1−0.1×10−2 ϕB1 0.77+0.02+0.16−0.02−0.12 2.81+0.13+0.28−0.12−0.31 8.64+0.66+1.79−0.61−1.73 2.9+0.1+0.1−0.1−0.1×10−2 2.2+0.1+0.1−0.0−0.1×10−2 data BaBar 4.4±0.8 5.4±0.9 7.1±0.7 S2 ϕB1 +ϕB2 0.76+0.02+0.15−0.02−0.11 3.09+0.14+0.22−0.13−0.26 10.04+0.70+1.73−0.65−1.70 4.7+0.1+0.0−0.1−0.0×10−2 2.4+0.1+0.1−0.1−0.1×10−2 ϕB1 0.72+0.02+0.13−0.01−0.10 2.47+0.11+0.23−0.10−0.26 6.95+0.52+1.43−0.48−1.38 2.7+0.1+0.1−0.1−0.1×10−2 2.0+0.0+0.1−0.0−0.1×10−2 data Belle 6.1±1.6 4.5±0.5 9.0±2.3 S3 ϕB1 +ϕB2 0.89+0.03+0.23−0.03−0.17 4.09+0.21+0.33−0.20−0.37 15.15+1.10+2.68−1.02−2.62 5.4+0.1+0.0−0.1−0.0×10−2 2.8+0.1+0.1−0.1−0.1×10−2 ϕB1 0.84+0.03+0.20−0.03−0.15 3.24+0.17+0.34−0.15−0.37 10.80+0.85+2.25−0.78−2.17 3.2+0.1+0.1−0.1−0.1×10−2 2.3+0.1+0.1−0.1−0.1×10−2 Table 4.
CP -averaged branching ratios (in the unit of10−6 ) forBd→PV decays. Other legends are the same as those of Table 3.mode LO NLO NLOG B−→π−ρ0 10.4+3.9−4.0 [49]9.0 [50]4.61±0.36 [54]5.4+1.6−1.2 [50]6.5 [51]7.2 [51]B−→π0ρ− 14.1 [50]8.73±0.25 [54]9.6+2.8−2.6 [50]13.3 [51]9.3 [51]B−→π−ω 11.3+3.6−3.2 [49]8.4 [50]4.6+1.4−1.1 [50]5.4 [51]6.1 [51]B−→K−K∗0 0.31+0.12−0.08 [52]0.42 [53]0.48±0.02 [54]0.32+0.12−0.08 [53]B−→K0K∗− 1.83+0.68−0.47 [52]0.20 [53]0.21+0.14−0.12 [53]B−→π0K∗− 4.0 [55]3.51±0.19 [54]4.3+5.0−2.2 [55]B−→K−ρ0 2.5 [55]2.24±0.41 [54]5.1+4.1−2.8 [55]B−→K−ω 2.1 [55]10.6+10.4−5.8 [55]B−→π−¯K∗0 5.5 [55]5.17±0.23 [54]6.0+2.8−1.5 [55]B−→¯K0ρ− 3.6 [55]3.39±0.55 [54]8.7+6.8−4.4 [55]B−→K−ϕ 13.8 [55]10.2 [48]7.8+5.9−1.8 [55]¯B0→π±ρ∓ 41.3 [50]23.3±0.8 [54]25.7+7.7−6.4 [50]27.8 [51]30.8 [51]¯B0→π0ω 0.22 [50]0.32+0.08−0.10 [50]0.04 [51]0.85 [51]¯B0→π0ρ0 0.15 [50]0.026±0.002 [54]0.37+0.13−0.10 [50]0.7 [51]1.1 [51]¯B0→π+K∗− 5.1 [55]4.93±0.28 [54]6.0+6.8−2.6 [55]¯B0→K−ρ+ 4.7 [55]4.4±0.6 [54]8.8+6.8−4.5 [55]¯B0→π0¯K∗0 1.5 [55]1.73±0.10 [54]2.0+1.2−0.6 [55]¯B0→{¯K0K∗0K0¯K∗0 1.96+0.79−0.54 [52]1.37 [53]0.85+0.26−0.21 [53]¯B0→¯K0ρ0 2.5 [55]3.06±0.37 [54]4.8+4.3−2.3 [55]¯B0→¯K0ω 1.9 [55]9.8+8.6−4.9 [55]¯B0→¯K0ϕ 12.9 [55]7.3+5.4−1.6 [55]¯B0→K±K∗∓ 0.07±0.01 [52]0.27 [53]0.13+0.05−0.07 [53]Table 5. Previous results of branching ratios (in the unit of
10−6 ) forB→PV decays, including the LO and NLO contributions using the PQCD approach, where NLO and NLOG represent those without and with Glauber effects, and the contributions from the B mesonic WFsϕB2 are not considered. If there are many theoretical uncertainties, the total uncertainties are given by the square roots of the sums of all quadratic errors. The details and meanings of the uncertainties can be found in their respective references.Figure 6. (color online)
χ2i distribution of branching ratios for three scenarios, where the numbers in the bar charts denote the values ofχ2i for a specific process.mode B−→π−ρ0 B−→π0ρ− B−→π−ω B−→π−ϕ data PDG 0.9±1.9 2±11 −4±5 9.8±51.1 S1 ϕB1 +ϕB2 −24.00+0.61+1.16−0.62−1.15 18.35+0.54+0.23−0.53−0.24 −1.67+0.01+0.26−0.01−0.26 0 ϕB1 −29.49+0.81+1.25−0.83−1.22 22.40+0.70+0.10−0.68−0.11 −4.36+0.02+0.18−0.02−0.18 0 data BaBar 18±17 −1±13 −2±8 S2 ϕB1 +ϕB2 −25.90+0.65+1.25−0.66−1.23 19.98+0.56+0.26−0.55−0.28 −1.66+0.01+0.26−−0.00−0.26 0 ϕB1 −32.02+0.86+1.35−0.88−1.32 24.52+0.73+0.13−0.72−0.14 −4.43+0.03+0.18−0.02−0.17 0 data Belle 6±18 −2±9 S3 ϕB1 +ϕB2 −22.20+0.58+1.08−0.59−1.07 16.80+0.51+0.20−0.50−0.21 −1.68+0.00+0.26−0.00−0.26 0 ϕB1 −27.09+0.77+1.15−0.78−1.12 20.38+0.66+0.08−0.65−0.09 −4.28+0.03+0.18−0.03−0.18 0 mode B−→K−K∗0 B−→K0K∗− B−→π0K∗− B−→K−ρ0 data PDG 12.3±9.8 −39±21 37±10 S1 ϕB1 +ϕB2 15.16+0.34+0.70−0.34−0.58 −25.13+2.03+13.90−1.99−7.02 −21.17+0.82+0.16−0.84−0.15 82.79+1.30+3.37−1.32−5.16 ϕB1 19.60+0.50+1.29−0.51−1.03 −11.19+1.82+7.91−1.77−4.25 −24.32+1.00+0.00−1.02−0.01 78.05+1.52+0.57−1.53−2.24 data BaBar −52±15 44±17 S2 ϕB1 +ϕB2 16.19+0.37+0.74−0.35−0.60 −19.01+2.03+13.91−2.05−8.18 −23.76+0.89+0.15−0.91−0.14 78.79+1.35+3.20−1.36−4.65 ϕB1 21.14+0.54+1.39−0.52−1.09 −5.72+1.82+8.30−1.83−5.14 −27.46+1.07+0.04−1.09−0.05 73.45+1.54+0.72−1.54−2.04 data Belle 30±16 S3 ϕB1 +ϕB2 14.18+0.32+0.68−0.31−0.55 −31.01+1.93+13.31−1.86−5.46 −18.78+0.75+0.16−0.77−0.15 86.60+1.20+3.42−1.24−5.63 ϕB1 18.12+0.48+1.22−0.47−0.96 −16.43+1.73+7.11−1.66−3.10 −21.41+0.92+0.04−0.95−0.04 82.55+1.45+0.28−1.48−2.37 mode B−→K−ω B−→π−¯K∗0 B−→¯K0ρ− B−→K−ϕ data PDG −2±4 −4±9 −3±15 2.4±2.8 S1 ϕB1 +ϕB2 20.64+0.37+1.48−0.38−1.06 −1.13+0.03+0.03−0.03−0.03 0.03+0.09+0.55−0.09−0.64 −0.55+0.01+0.02−0.01−0.03 ϕB1 22.70+0.32+2.07−0.33−1.50 −1.48+0.05+0.05−0.05−0.06 −0.12+0.09+0.36−0.08−0.42 −0.69+0.02+0.04−0.02−0.06 data BaBar −1±7 −12±25 21±31 12.8±4.6 S2 ϕB1 +ϕB2 21.75+0.35+1.42−0.36−1.01 −1.23+0.03+0.03−0.03−0.03 −0.22+0.08+0.51−0.07−0.56 −0.59+0.01+0.02−0.02−0.03 ϕB1 23.61+0.27+1.99−0.29−1.44 −1.63+0.05+0.06−0.05−0.06 −0.36+0.08+0.34−0.07−0.38 −0.76+0.02+0.04−0.02−0.06 data Belle −3±4 −14.9±6.8 1±13 S3 ϕB1 +ϕB2 19.49+0.39+1.53−0.40−1.09 −1.04+0.03+0.02−0.03−0.03 0.30+0.10+0.58−0.10−0.71 −0.51+0.01+0.02−0.01−0.03 ϕB1 21.66+0.36+2.13−0.38−1.53 −1.34+0.04+0.05−0.04−0.05 0.14+0.09+0.37−0.09−0.47 −0.64+0.02+0.04−0.02−0.05 Table 6. Direct
CP -violating asymmetries (ACP , in the unit of percentage) forBu→PV decays. Other legends are the same as those of Table 3.ACP mode ¯B0→π+ρ− ¯B0→π−ρ+ ¯B0→π+K∗− ¯B0→K−ρ+ data PDG 13±6 −8±8 −27±4 20±11 S1 ϕB1 +ϕB2 4.04+0.27+0.77−0.26−0.80 −19.80+0.35+0.18−0.36−0.13 −31.04+1.13+0.29−1.15−0.33 86.31+0.61+2.50−0.71−4.95 ϕB1 7.20+0.37+0.76−0.36−0.80 −22.88+0.48+0.26−0.48−0.18 −35.44+1.28+0.64−1.29−0.74 74.34+0.83+3.15−0.92−4.75 data BaBar 9±7 −12±9 −29±11 20±12 S2 ϕB1 +ϕB2 4.87+0.29+0.77−0.28−0.81 −20.91+0.38+0.12−0.38−0.06 −34.56+1.19+0.36−1.21−0.40 83.91+0.89+1.48−0.97−3.71 ϕB1 8.33+0.39+0.76−0.39−0.80 −24.36+0.51+0.18−0.51−0.10 −39.34+1.30+0.75−1.30−0.85 71.37+1.06+2.15−1.13−3.61 data Belle 21±9 8±19 −21±13 22±24 S3 ϕB1 +ϕB2 3.27+0.25+0.76−0.24−0.79 −18.77+0.33+0.23−0.34−0.19 −27.72+1.06+0.24−1.09−0.27 87.84+0.29+3.77−0.40−6.31 ϕB1 6.14+0.34+0.75−0.33−0.80 −21.48+0.45+0.33−0.46−0.26 −31.64+1.23+0.55−1.25−0.63 76.57+0.55+4.41−0.65−6.03 ACP mode ¯B0→π0¯K∗0 ¯B0→¯K0ρ0 ¯B0→¯K0ω ¯B0→¯K0ϕ data PDG −15±13 −4±20 0±40 1±14 S1 ϕB1 +ϕB2 −0.47+0.09+0.01−0.08−0.01 −5.47+0.16+1.72−0.15−2.25 3.12+0.04+0.35−0.04−0.29 0 ϕB1 −1.33+0.12+0.03−0.10−0.02 −6.57+0.20+1.80−0.19−2.27 4.58+0.05+0.45−0.05−0.35 0 data BaBar −15±13 −5±28 −52±22 5±19 S2 ϕB1 +ϕB2 −0.20+0.10+0.01−0.10−0.01 −5.88+0.12+1.65−0.11−2.03 3.23+0.03+0.35−0.03−0.29 0 ϕB1 −0.96+0.14+0.02−0.13−0.01 −7.08+0.15+1.69−0.14−2.02 4.71+0.04+0.44−0.04−0.34 0 data Belle −3±28 36±20 −4±22 S3 ϕB1 +ϕB2 −0.69+0.07+0.03−0.06−0.03 −4.97+0.19+1.75−0.18−2.42 3.00+0.04+0.36−0.04−0.29 0 ϕB1 −1.62+0.09+0.06−0.08−0.06 −5.93+0.24+1.86−0.23−2.48 4.41+0.06+0.46−0.06−0.36 0 mode ¯B0→π0ρ0 ¯B0→π0ω Cf Sf Cf Sf data PDG 27±24 −23±34 S1 ϕB1 +ϕB2 −0.04+0.14+0.31−0.21−0.50 −89.75+0.46+2.11−0.45−1.82 −67.36+1.06+0.75−1.05−0.73 24.00+0.40+1.86−0.40−1.78 ϕB1 −22.82+0.03+0.11−0.06−0.22 −74.39+0.50+3.22−0.49−2.90 −66.52+1.05+0.33−1.04−0.32 39.32+0.41+0.97−0.42−0.89 data BaBar 19±27 −37±39 S2 ϕB1 +ϕB2 0.49+0.21+0.26−0.18−0.42 −88.39+0.46+2.27−0.45−1.96 −70.49+1.05+0.82−1.03−0.79 25.15+0.32+1.79−0.38−1.74 ϕB1 −22.65+0.09+0.10−0.08−0.20 −73.00+0.42+3.28−0.43−2.98 −69.62+1.03+0.36−1.03−0.36 40.43+0.28+0.85−0.35−0.79 data Belle 49±46 17±67 S3 ϕB1 +ϕB2 −0.57+0.13+0.43−0.11−0.57 −91.10+0.46+1.94−0.45−1.64 −64.23+1.05+0.67−1.03−0.65 22.69+0.46+1.91−0.46−1.84 ϕB1 −22.90+0.05+0.15−0.01−0.23 −76.00+0.58+3.11−0.60−2.78 −63.47+1.00+0.27−1.00−0.27 37.90+0.53+1.07−0.55−1.00 Table 7.
CP -violating asymmetries (in the unit of percentage) forBd decays. Other legends are the same as those of Table 3.π+ρ− ,π−ρ+ aϵ′ aϵ+ϵ′ ˉaϵ′ ˉaϵ+ϵ′ data PDG −3±7 5±7 S1 ϕB1 +ϕB2 −19.23+0.34+3.24−0.34−3.06 9.05+0.03+1.00−0.03−1.00 27.32+0.22+3.26−0.22−3.46 12.71+0.09+1.36−0.09−1.36 ϕB1 −22.66+0.38+4.00−0.38−3.72 9.78+0.03+1.14−0.03−1.15 32.52+0.21+4.04−0.20−4.37 9.60+0.04+1.60−0.04−1.59 data BaBar 1.6±6.9 5.3±8.8 S2 ϕB1 +ϕB2 −18.25+0.31+3.18−0.32−3.00 8.97+0.02+0.96−0.03−0.96 26.71+0.19+3.24−0.19−3.43 12.99+0.10+1.33−0.10−1.34 ϕB1 −21.56+0.34+3.95−0.36−3.68 9.88+0.03+1.09−0.04−1.09 31.97+0.17+4.05−0.16−4.37 9.70+0.04+1.57−0.04−1.57 data Belle −13±10 6±14 S3 ϕB1 +ϕB2 −20.29+0.36+3.30−0.38−3.11 9.13+0.03+1.04−0.03−1.04 28.03+0.26+3.28−0.25−3.49 12.44+0.09+1.38−0.09−1.38 ϕB1 −23.84+0.41+4.05−0.42−3.75 9.68+0.04+1.20−0.03−1.19 33.19+0.25+4.02−0.23−4.36 9.50+0.03+1.62−0.04−1.61 ¯K0K∗0 ,K0¯K∗0 aϵ′ aϵ+ϵ′ ˉaϵ′ ˉaϵ+ϵ′ data PDG S1 ϕB1 +ϕB2 −76.49+1.10+1.14−1.05−0.53 58.96+1.43+4.66−1.42−4.44 76.49+1.05+0.53−1.10−1.14 −58.96+1.42+4.44−1.43−4.66 ϕB1 −64.09+1.43+1.69−1.37−0.24 61.42+1.34+6.32−1.34−5.61 64.09+1.37+0.24−1.43−1.69 −61.42+1.34+5.61−1.34−6.32 data BaBar S2 ϕB1 +ϕB2 −73.04+1.25+1.01−1.20−0.69 63.22+1.40+4.78−1.41−4.61 73.04+1.20+0.69−1.25−1.01 −63.22+1.41+4.61−1.40−4.78 ϕB1 −59.64+1.58+1.11−1.53−0.43 65.34+1.24+6.41−1.27−5.78 59.64+1.53+0.43−1.58−1.11 −65.34+1.27+5.78−1.24−6.41 data Belle S3 ϕB1 +ϕB2 −79.48+0.95+1.56−0.90−0.05 54.71+1.41+4.50−1.40−4.25 79.48+0.90+0.05−0.95−1.56 −54.71+1.40+4.25−1.41−4.50 ϕB1 −68.05+1.27+2.23−1.22−0.89 57.33+1.37+6.13−1.39−5.39 68.05+1.22+0.89−1.27−2.23 −57.33+1.39+5.39−1.37−6.13 K+K∗− ,K−K∗+ aϵ′ aϵ+ϵ′ ˉaϵ′ ˉaϵ+ϵ′ data PDG S1 ϕB1 +ϕB2 −14.02+0.79+0.86−0.71−0.95 −38.60+−0.01+0.60−0.03−0.62 67.26+0.34+0.17−0.32−0.10 −11.47+0.44+0.69−0.47−0.69 ϕB1 11.39+0.07+0.17−−0.05−0.23 −41.60+0.20+0.63−0.17−0.56 27.65+0.89+0.42−0.88−0.38 −1.97+0.05+1.45−0.15−1.41 data BaBar S2 ϕB1 +ϕB2 −16.09+0.63+0.79−0.72−0.87 −38.54+0.05+0.58−0.04−0.63 66.24+0.40+0.15−0.33−0.11 −10.14+0.46+0.73−0.44−0.71 ϕB1 11.56+−0.01+0.07−0.12−0.14 −40.90+0.25+0.63−0.27−0.63 25.04+0.94+0.45−0.86−0.46 −1.80+0.07+1.47−0.04−1.38 data Belle S3 ϕB1 +ϕB2 −11.66+0.89+0.93−0.81−1.03 −38.60+−0.02+0.63−0.04−0.66 68.33+0.31+0.13−0.38−0.12 −12.84+0.48+0.69−0.50−0.64 ϕB1 11.38+0.05+0.25−−0.04−0.29 −42.02+0.09+0.67−0.07−0.62 30.49+0.95+0.32−1.03−0.34 −2.33+0.14+1.48−0.19−1.35 Table 8.
CP -violating asymmetries (in the unit of percentage) for Case 3Bd decays. Other legends are the same as those of Table 3.(1) As shown in Tables 3 and 4, except for the
B−→¯K0ρ− andK0K∗− decays, the contributions from the B mesonic WFsϕB2 can enhance the branching ratios compared with those fromϕB1 . The contributions fromϕB2 to the branching ratios are approximately30 % and sometimes more, except for the¯B→Kρ ,Kω ,πϕ ,π0ρ0 ,K0K∗− , andK−K∗+ decays. In addition, as shown in Tables 5, various results are obtained with the PQCD approach at the LO and NLO levels. The previous PQCD studies in Refs. [50, 53, 55] have shown that the NLO contributions can sometimes enhance and sometimes lessen the LO branching ratios. The shares fromϕB2 to the branching ratios are comparable to the module of the shares from the NLO contributions. Taking the branching ratios for theB−→π−ρ0 (K−K∗0 ) decays as an example, the shares fromϕB2 are approximately37 % (30 %), and the shares from the NLO contributions are approximately40 % [50] (24 % [53]). On the whole, considerably more effort is required to further improve the agreement between the theoretical results and data.(2) As shown in Tables 6 and 7, the participation of the WFs
ϕB2 results in a small reduction in the directCP asymmetries, except for the¯B→K−ρ andK0K∗− decays. As is well known, the theoretical results of theCP asymmetries are highly sensitive to the strong phases. Therefore, it is essential to obtain the strong phases as accurately as possible. There are numerous sources of strong phases, such as the higher order radiative corrections to HMEs and final state interactions. In this paper,CP asymmetries are calculated at the LO order, and many factors that might affect these asymmetries are not carefully considered owing to our inadequate comprehension. For instance, there are still many theoretical and experimental discrepancies on the branching ratios. Therefore, ourCP asymmetry estimations in Tables 6, 7, and 8 cannot be taken too literally. Moreover, it is assumed that the current precision of most measurements ofCP asymmetries is too low to impose helpful constraints. Given their theoretical and experimental research status,CP asymmetries are not considered in the fit with Eq. (55). In addition, it is shown in the amplitudes of Eq. (A4), Eq. (A19), and Eq. (A25) that tree amplitudes are absent and only the penguin contributions participate. These facts result in unavailable weak phase differences, which are an essential ingredient of directCP asymmetries. Therefore, it is not surprising that the theoretical expectations of the directCP asymmetries for theB−→π−ϕ and¯B0→π0ϕ ,¯K0ϕ decays are exactly zero. For¯B0→¯K0K∗0+K0¯K∗0 decays, which are induced by the pure penguin amplitudes in Eq. (A17) and Eq. (A18), the parametersλf of Eq. (53) andˉλf of Eq. (54) contain only strong phase information. The measurements of the observablesaϵ′=−ˉaϵ′ andaϵ+ϵ′=−ˉaϵ+ϵ′ would be helpful for testing our understanding on the strong interactions in nonleptonic B meson weak decays.(3) It is clear in Fig. 6 that for S1, the goodness of fit between the PDG group data and PQCD results is still far from satisfactory. Among the 19
B→PV decays, there are only four decay modes withχ2i<9 , which indicates that the theoretical results on the branching ratios for theB−→π0ρ− ,π−ϕ ,¯B0→π±ρ∓ , and¯K0ρ0 decays agree with the PDG data within three standard experimental errors. The minimalχ2i≈1.3 is obtained for theB−→π−ϕ decay, where the relative fitting error is significantly large and can reach up to approximately47 %. (Note: There is a general and conventional consensus in elementary particle physics that a signal or event with a statistic significance of less than3σ , more than3σ , and more than5σ are respectively known as a hint (or an indication), an evidence, and a discovery (or an observation or a confirmation), usually with a relative error greater than33.3 %, lower than33.3 %, and lower than20 %.) There are eight decay modes withχ2i>25 , which suggests that the discrepancies between theoretical calculations and the data are larger than five standard experimental errors, and the theoretical results on theB−→π−ω ,K−ρ0 ,K−ω ,K−ϕ ,π−¯K∗0 and¯B0→π+K∗− ,K−ρ+ ,¯K0ϕ decays fail to provide a satisfactory explanation for the PDG data. The maximalχ2i≈94 is found for the¯B0→π+K∗− decay, where the relative fitting error is significantly small at approximately5 %. It should be noted that the disagreement about the¯B0→π+K∗− decay has been reported by previous PQCD studies in which only theϕB1 contributions were considered, for example,χ2i≈36 (14 ) with the LO (NLO) contributions [55] andχ2i≈41 with the recent global analysis of B decays [54] at the LO level. For S2 (S3), there are seven (six) decay modes withχ2i<9 .B−→K−ϕ is the only decay withχ2i just above25 in S3. In both scenarios, theB−→π0ρ− and¯B0→π±ρ∓ decays haveχ2i<9 at present.(4) As shown in Fig. 6, there are four decays with
χ2i≥50 in S1, including theB−→K−ω ,π−¯K∗0 and¯B0→π+K∗− ,¯K0ϕ decays. To further explore other possible underlying causes for the relatively largerχ2min for S1 besides the relatively smaller errors in the PDG data, the relations of the branching ratios versus the shape parameterωB are shown in Fig. 7. There are several clear and attractive phenomena evident in Fig. 7. (i) Most of the branching ratios decrease with an increase in the parameterωB . This situation is similar to that of form factors in Fig. 3. It is easy to understand this phenomenon because decay amplitudes are usually proportional to form factors. (ii) The current PDG data on theB−→¯K0ρ− ,K−ρ0 and¯B0→K−ρ+ ,π0ρ0 decays cannot be satisfactorily explained using the PQCD approach within3σ regions, no matter which value is taken for the parameter within0.3 GeV≤ωB≤0.6 GeV. These four decays contribute a largeχ2i>9 . In addition, the branching ratios of these four decays are insensitive to the parameterωB . (iii) When the pseudoscalar pion meson is one of the final states, branching ratios change significantly with the parameterωB , except for the above mentioned¯B0→π0ρ0 decay. A smallωB<0.4 GeV is commonly favored by most B decays, except for theB−→π−ϕ decay. Although the PGD data opt for a largeωB for theB−→π−ϕ decay, the value ofωB=0.4 GeV can also marginally meet the experimental3σ constraints. The S1 parameterωB=0.46 GeV is somewhat large and should be decreased forB→πV decays, which results in the extraordinarily largeχ2i≈38 ,50 , and94 corresponding respectively to the¯B→π−ω ,π−¯K∗0 , andπ+¯K∗0 decays. (iv) When the pseudoscalar kaon meson is one of the final states, the PDG data impose inconsistent requirements on the parameterωB , that is,ωB<0.45 GeV for the¯B→¯Kω ,K−K∗0 decays, andωB>0.5 GeV for the¯B→¯Kϕ decays. The positive and negative deviations fromωB=0.46 GeV facilitateχ2i for the¯B→K−ω ,K−ϕ , and¯K0ϕ decays to59 ,45 , and51 , respectively. (v) The general conclusion about S1 is that, on the one hand, a relatively smallωB is favored by the¯B→¯Kω decays and most of the¯B→πV decays. On the other hand, a relatively largeωB is favored by the¯B→Pϕ decays. Furthermore, the¯B→¯Kρ decays are insensitive to changes inωB .Figure 7. (color online) Branching ratios vs the shape parameter
ωB , where the relatively narrower (wider) horizontal bands denote the PGD data within±1σ (±3σ ) regions, the curves in red are the PQCD results, including contributions fromϕB2 , the curvy bands in pink denote the theoretical uncertainties from the chiral massμP=1.4±0.1 GeV, and the points in black denote the S1 results.(5) As shown in Table 5, previous PQCD results without contributions from the B mesonic WFs
ϕB2 could also provide a satisfactory explanation for many of theB→PV decays by choosing appropriate parameters, such asωB . In other words, to some extent, the effects ofϕB2 on nonleptonic B decays could be replaced by other scenarios of input parameters, which might be one reason why the contributions ofϕB2 were often not seriously considered in previous studies. To further illustrate the influences ofϕB2 onB→PV decays, consistencies between the experimental data and PQCD results with differentωB are shown in Figs. 8 and 9. It is clear from Fig. 8 that when contributions from the B mesonic WFsϕB2 are not taken into account, the optimal parameterωB and the minimumχ2 corresponding to experimental data from the BaBar and Belle groups are, respectively,Figure 8. (color online) Distribution of
χ2 versus the shape parameterωB with and without the contributions ofϕB2 .Figure 9. (color online)
χ2i distribution of branching ratios with and without the contributions ofϕB2 , where the numbers in the bar charts denote the values ofχ2i for a specific process.● Scenario 4 (S4):
ωB=0.44 GeV from BaBar data withχ2min.≈262 ,● Scenario 5 (S5):
ωB=0.39 GeV from Belle data withχ2min.≈154 .The value of
ωB for S4 (S5) is less than that for S2 (S3). The value ofχ2min. for S4 (S5) is larger than that for S2 (S3). As shown in Fig. 9, (i) there are five decay modes withχ2i<9 for S4, which is fewer than the seven decay modes withχ2i<9 for S2. (ii) There are six same decay modes withχ2i<9 for both S3 and S5, including theB−→π−ρ0 ,π0ρ− and¯B0→π±ρ∓ ,π+¯K∗− ,¯K0ω ,¯K0ϕ decays. Among these six same decays, except for the¯B0→¯K0ϕ decay, theχ2i of the other decays for S5 are larger than that for S3. A conclusion from the comparative analysis of Figs. 8 and 9 is that a more comprehensive agreement of branching ratios between the PQCD calculations and experimental data can be improved by the participation of the B mesonic WFsϕB2 . -
In this study, inspired by the experimental prospects of B meson physics, we reinvestigate
B→PV decays (P=π and K) at the LO order using the PQCD approach within the SM by considering the B mesonic WFsϕB2 , which have been excluded in previous phenomenological studies. In the convolution integrals of the HMEs of nonleptonic B decays, the WFsϕB2 are involved in the emission amplitudes and nonfactorizable annihilation amplitudes. Contributions fromϕB2 can enhance the hadronic transition form factorsF1(0) andA0(0) . The form factors are highly sensitive to the shape parameterωB of B mesonic WFs. By fitting the PQCD results with the branching ratios and experimental data using the minimumχ2 method, it is found that the participation ofϕB2 is helpful for improving the comprehensive agreement between the PQCD calculations and experimental data. The shares ofϕB2 should be given due attention and studied meticulously for nonleptonic B decays. When contributions fromϕB2 are considered, three optimal scenarios of the parameterωB are found. The PQCD results on branching ratios andCP asymmetries are updated with these three scenarios. It is found that in any one of these scenarios, theϕB2 contributions can increase most branching ratios, except for theB−→K0K∗− ,¯K0ρ− decays. In contrast, these contributions can decrease most directCP asymmetries, except in the¯B→K−ρ andK0K∗− decays. However, it should be noted that there are still several discrepancies between the PQCD results and available data to a greater or lesser extent. More worthwhile endeavors on nonleptonic B decays are required, experimentally and theoretically. From the experimental perspective, an increasing number of accurate measurement results are being produced within existing and future experiments. From the theoretical perspective, at the quark level, other possible mechanisms of the interactions and higher order corrections of scattering amplitudes are highly important; at the hadron level, some appropriate models for mesonic WFs including higher twist components are essential. -
Using the
SU(3) flavor structure, a more concise and compact amplitude for theB→PP ,PV decays is given by Eq. (12) in Ref. [54] with the PQCD approach. The analytical expressions are explicitly listed below.A(B−u→π−ρ0)=GF2VubV∗ud{a1[ALLab(π,ρ)+ALLef(π,ρ)−ALLef(ρ,π)]+a2ALLab(ρ,π)+C2[ALLcd(π,ρ)+ALLgh(π,ρ)−ALLgh(ρ,π)]+C1ALLcd(ρ,π)}−GF2VtbV∗td{(a4+a10)[ALLab(π,ρ)+ALLef(π,ρ)−ALLef(ρ,π)]+(a6+a8)[ASPab(π,ρ)+ASPef(π,ρ)−ASPef(ρ,π)]−(a4−32a7−32a9−12a10)ALLab(ρ,π)+(C3+C9)[ALLcd(π,ρ)+ALLgh(π,ρ)−ALLgh(ρ,π)]+(C5+C7)[ASPcd(π,ρ)+ASPgh(π,ρ)−ASPgh(ρ,π)]−(C3−32C10−12C9)ALLcd(ρ,π)+32C8ALRcd(ρ,π)−(C5−12C7)ASPcd(ρ,π)}, A(B−u→ρ−π0)=GF2VubV∗ud{a1[ALLab(ρ,π)+ALLef(ρ,π)−ALLef(π,ρ)]+a2ALLab(π,ρ)+C2[ALLcd(ρ,π)+ALLgh(ρ,π)−ALLgh(π,ρ)]+C1ALLcd(π,ρ)}−GF2VtbV∗td{(a4+a10)[ALLab(ρ,π)+ALLef(ρ,π)−ALLef(π,ρ)]+(a6+a8)[ASPef(ρ,π)−ASPef(π,ρ)]−(a6−12a8)ASPab(π,ρ)−(a4+32a7−32a9−12a10)ALLab(π,ρ)+(C5+C7)ASPcd(ρ,π)+(C3+C9)[ALLcd(ρ,π)+ALLgh(ρ,π)−ALLgh(π,ρ)]+(C5+C7)[ASPgh(ρ,π)−ASPgh(π,ρ)]−(C5−12C7)ASPcd(π,ρ)−(C3−32C10−12C9)ALLcd(π,ρ)+32C8ALRcd(π,ρ)},
A(B−u→π−ω)=GF2VubV∗ud{a1[ALLab(π,ω)+ALLef(π,ω)+ALLef(ω,π)]+a2ALLab(ω,π)+C2[ALLcd(π,ω)+ALLgh(π,ω)+ALLgh(ω,π)]+C1ALLcd(ω,π)}−GF2VtbV∗td{(a4+a10)[ALLab(π,ω)+ALLef(π,ω)+ALLef(ω,π)]+(a6+a8)[ASPab(π,ω)+ASPef(π,ω)+ASPef(ω,π)]+(2a3+a4+2a5+12a7+12a9−12a10)ALLab(ω,π)+(C3+C9)[ALLcd(π,ω)+ALLgh(π,ω)+ALLgh(ω,π)]+(C5+C7)[ASPcd(π,ω)+ASPgh(π,ω)+ASPgh(ω,π)]+(C3+2C4−12C9+12C10)ALLcd(ω,π)+(2C6+12C8)ALRcd(ω,π)+(C5−12C7)ASPcd(ω,π)},
A(B−u→π−ϕ)=−GF√2VtbV∗td{(a3+a5−12a7−12a9)ALLab(ϕ,π)+(C4−12C10)ALLcd(ϕ,π)+(C6−12C8)ALRcd(ϕ,π)},
A(B−u→K−K∗0)=GF√2VubV∗ud{a1ALLef(K∗,¯K)+C2ALLgh(K∗,¯K)}−GF√2VtbV∗td{(a4−12a10)ALLab(K∗,¯K)+(C3−12C9)ALLcd(K∗,¯K)+(a4+a10)ALLef(K∗,¯K)+(C3+C9)ALLgh(K∗,¯K)+(a6+a8)ASPef(K∗,¯K)+(C5+C7)ASPgh(K∗,¯K)+(C5−12C7)ASPcd(K∗,¯K)},
A(B−u→K∗−K0)=GF√2VubV∗ud{a1ALLef(K,¯K∗)+C2ALLgh(K,¯K∗)}−GF√2VtbV∗td{(a4−12a10)ALLab(K,¯K∗)+(a4+a10)ALLef(K,¯K∗)+(a6−12a8)ASPab(K,¯K∗)+(a6+a8)ASPef(K,¯K∗)+(C3−12C9)ALLcd(K,¯K∗)+(C3+C9)ALLgh(K,¯K∗)+(C5−12C7)ASPcd(K,¯K∗)+(C5+C7)ASPgh(K,¯K∗)},
A(B−u→K∗−π0)=GF2VubV∗us{a1[ALLab(¯K∗,π)+ALLef(¯K∗,π)]+a2ALLab(π,¯K∗)+C2[ALLcd(¯K∗,π)+ALLgh(¯K∗,π)]+C1ALLcd(π,¯K∗)}−GF2VtbV∗ts{(a4+a10)[ALLab(¯K∗,π)+ALLef(¯K∗,π)]+(a6+a8)ASPef(¯K∗,π)−32(a7−a9)ALLab(π,¯K∗)+(C3+C9)[ALLcd(¯K∗,π)+ALLgh(¯K∗,π)]+(C5+C7)[ASPcd(¯K∗,π)+ASPgh(¯K∗,π)]+32C8ALRcd(π,¯K∗)+32C10ALLcd(π,¯K∗)},
A(B−u→K−ρ0)=GF2VubV∗us{a1[ALLab(¯K,ρ)+ALLef(¯K,ρ)]+a2ALLab(ρ,¯K)+C2[ALLcd(¯K,ρ)+ALLgh(¯K,ρ)]+C1ALLcd(ρ,¯K)}−GF2VtbV∗ts{(a4+a10)[ALLab(¯K,ρ)+ALLef(¯K,ρ)]+(a6+a8)[ASPab(¯K,ρ)+ASPef(¯K,ρ)]+32(a7+a9)ALLab(ρ,¯K)+(C3+C9)[ALLcd(¯K,ρ)+ALLgh(¯K,ρ)]+(C5+C7)[ASPcd(¯K,ρ)+ASPgh(¯K,ρ)]+32C8ALRcd(ρ,¯K)+32C10ALLcd(ρ,¯K)},
A(B−u→K−ω)=GF2VubV∗us{a1[ALLab(¯K,ω)+ALLef(¯K,ω)]+a2ALLab(ω,¯K)+C2[ALLcd(¯K,ω)+ALLgh(¯K,ω)]+C1ALLcd(ω,¯K)}−GF2VtbV∗ts{(a4+a10)[ALLab(¯K,ω)+ALLef(¯K,ω)]+(a6+a8)[ASPab(¯K,ω)+ASPef(¯K,ω)]+(2a3+2a5+12a7+12a9)ALLab(ω,¯K)+(C3+C9)[ALLcd(¯K,ω)+ALLgh(¯K,ω)]+(C5+C7)[ASPcd(¯K,ω)+ASPgh(¯K,ω)]+(2C6+12C8)ALRcd(ω,¯K)+(2C4+12C10)ALLcd(ω,¯K)},
A(B−u→π−¯K∗0)=GF√2VubV∗us{a1ALLef(¯K∗,π)+C2ALLgh(¯K∗,π)}−GF√2VtbV∗ts{(a4−12a10)ALLab(¯K∗,π)+(C3−12C9)ALLcd(¯K∗,π)+(a4+a10)ALLef(¯K∗,π)+(C3+C9)ALLgh(¯K∗,π)+(a6+a8)ASPef(¯K∗,π)+(C5+C7)ASPgh(¯K∗,π)+(C5−12C7)ASPcd(¯K∗,π)},
A(B−u→ρ−¯K0)=GF√2VubV∗us{a1ALLef(¯K,ρ)+C2ALLgh(¯K,ρ)}−GF√2VtbV∗ts{(a4−12a10)ALLab(¯K,ρ)+(C3−12C9)ALLcd(¯K,ρ)+(a4+a10)ALLef(¯K,ρ)+(C3+C9)ALLgh(¯K,ρ)+(a6−12a8)ASPab(¯K,ρ)+(C5−12C7)ASPcd(¯K,ρ)+(a6+a8)ASPef(¯K,ρ)+(C5+C7)ASPgh(¯K,ρ)},
A(B−u→K−ϕ)=GF√2VubV∗us{a1ALLef(ϕ,¯K)+C2ALLgh(ϕ,¯K)}−GF√2VtbV∗ts{(a3+a4+a5−12a7−12a9−12a10)ALLab(ϕ,¯K)+(a4+a10)ALLef(ϕ,¯K)+(a6+a8)ASPef(ϕ,¯K)+(C3+C4−12C9−12C10)ALLcd(ϕ,¯K)+(C6−12C8)ALRcd(ϕ,¯K)+(C5−12C7)ASPcd(ϕ,¯K)+(C3+C9)ALLgh(ϕ,¯K)+(C5+C7)ASPgh(ϕ,¯K)},
A(¯B0d→ρ−π+)=GF√2VubV∗ud{a1ALLab(ρ,π)+C2ALLcd(ρ,π)+a2ALLef(π,ρ)+C1ALLgh(π,ρ)}−GF√2VtbV∗td{(a4+a10)×ALLab(ρ,π)+(C3+C9)ALLcd(ρ,π)+(a3+a4−a5+12a7−12a9−12a10)ALLef(ρ,π)+(C3+C4−12C9−12C10)ALLgh(ρ,π)+(C6−12C8)ALRgh(ρ,π)+(a6−12a8)ASPef(ρ,π)+(C5−12C7)ASPgh(ρ,π)+(a3−a5−a7+a9)ALLef(π,ρ)+(C4+C10)ALLgh(π,ρ)+(C6+C8)ALRgh(π,ρ)+(C5+C7)ASPcd(ρ,π)},
A(¯B0d→π−ρ+)=GF√2VubV∗ud{a1ALLab(π,ρ)+C2ALLcd(π,ρ)+a2ALLef(ρ,π)+C1ALLgh(ρ,π)}−GF√2VtbV∗td{(a4+a10)×ALLab(π,ρ)+(C3+C9)ALLcd(π,ρ)+(a6+a8)ASPab(π,ρ)+(C5+C7)ASPcd(π,ρ)+(a3+a4−a5+12a7−12a9−12a10)ALLef(π,ρ)+(C3+C4−12C9−12C10)ALLgh(π,ρ)+(C6−12C8)ALRgh(π,ρ)+(a6−12a8)ASPef(π,ρ)+(C5−12C7)ASPgh(π,ρ)+(a3−a5−a7+a9)ALLef(ρ,π)+(C4+C10)ALLgh(ρ,π)+(C6+C8)ALRgh(ρ,π)},
A(¯B0d→π0ρ0)=GF2√2VubV∗ud{a2[−ALLab(π,ρ)−ALLab(ρ,π)+ALLef(π,ρ)+ALLef(ρ,π)]+C1[−ALLcd(π,ρ)−ALLcd(ρ,π)+ALLgh(π,ρ)+ALLgh(ρ,π)]}−GF2√2VtbV∗td{(a4−32a9−12a10)[ALLab(π,ρ)+ALLab(ρ,π)]+32a7[ALLab(π,ρ)−ALLab(ρ,π)]+(C3−12C9−32C10)[ALLcd(π,ρ)+ALLcd(ρ,π)]−32C8[ALRcd(π,ρ)+ALRcd(ρ,π)]+(a6−12a8)[ASPab(π,ρ)+ASPef(π,ρ)+ASPef(ρ,π)]+(C5−12C7)[ASPcd(π,ρ)+ASPcd(ρ,π)+ASPgh(π,ρ)+ASPgh(ρ,π)]+(2a3+a4−2a5−12a7+12a9−12a10)[ALLef(π,ρ)+ALLef(ρ,π)]+(C3+2C4−12C9+12C10)[ALLgh(π,ρ)+ALLgh(ρ,π)]+(2C6+12C8)[ALRgh(π,ρ)+ALRgh(ρ,π)]},
A(¯B0d→π0ω)=GF2√2VubV∗ud{a2[ALLab(π,ω)−ALLab(ω,π)+ALLef(π,ω)+ALLef(ω,π)]+C1[ALLcd(π,ω)−ALLcd(ω,π)+ALLgh(π,ω)+ALLgh(ω,π)]}−GF2√2VtbV∗td{−(2a3+a4+2a5+12a7+12a9−12a10)ALLab(ω,π)−(C3+2C4−12C9+12C10)ALLcd(ω,π)−(2C6+12C8)ALRcd(ω,π)−(a4+32a7−32a9−12a10)[ALLab(π,ω)+ALLef(π,ω)+ALLef(ω,π)]−(C3−12C9−32C10)[ALLcd(π,ω)+ALLgh(π,ω)+ALLgh(ω,π)]+32C8[ALRcd(π,ω)+ALRgh(π,ω)+ALRgh(ω,π)]−(a6−12a8)[ASPab(π,ω)+ASPef(π,ω)+ASPef(ω,π)]−(C5−12C7)[ASPcd(π,ω)+ASPcd(ω,π)+ASPgh(π,ω)+ASPgh(ω,π)]},
A(¯B0d→¯K0K∗0)=−GF√2VtbV∗td{(a4−12a10)[ALLab(K∗,¯K)+ALLef(K∗,¯K)]+(C3−12C9)[ALLcd(K∗,¯K)+ALLgh(K∗,¯K)]+(a6−12a8)ASPef(K∗,¯K)+(C5−12C7)[ASPcd(K∗,¯K)+ASPgh(K∗,¯K)]+(a3−a5+12a7−12a9)[ALLef(K∗,¯K)+ALLef(¯K,K∗)]+(C4−12C10)[ALLgh(K∗,¯K)+ALLgh(¯K,K∗)]+(C6−12C8)[ALRgh(K∗,¯K)+ALRgh(¯K,K∗)]},
A(¯B0d→¯K∗0K0)=−GF√2VtbV∗td{(a4−12a10)[ALLab(K,¯K∗)+ALLef(K,¯K∗)]+(C3−12C9)[ALLcd(K,¯K∗)+ALLgh(K,¯K∗)]+(a6−12a8)[ASPab(K,¯K∗)+ASPef(K,¯K∗)]+(C5−12C7)[ASPcd(K,¯K∗)+ASPgh(K,¯K∗)]+(a3−a5+12a7−12a9)[ALLef(K,¯K∗)+ALLef(¯K∗,K)]+(C4−12C10)[ALLgh(K,¯K∗)+ALLgh(¯K∗,K)]+(C6−12C8)[ALRgh(K,¯K∗)+ALRgh(¯K∗,K)]},
A(¯B0d→π0ϕ)=GF2VtbV∗td{(a3+a5−12a7−12a9)ALLab(ϕ,π)+(C4−12C10)ALLcd(ϕ,π)+(C6−12C8)ALRcd(ϕ,π)},
A(¯B0d→K∗−π+)=GF√2VubV∗us{a1ALLab(¯K∗,π)+C2ALLcd(¯K∗,π)}−GF√2VtbV∗ts{(a4+a10)ALLab(¯K∗,π)+(C3+C9)ALLcd(¯K∗,π)+(a4−12a10)ALLef(¯K∗,π)+(C3−12C9)ALLgh(¯K∗,π)+(a6−12a8)ASPef(¯K∗,π)+(C5−12C7)ASPgh(¯K∗,π)+(C5+C7)ASPcd(¯K∗,π)},
A(¯B0d→K−ρ+)=GF√2VubV∗us{a1ALLab(¯K,ρ)+C2ALLcd(¯K,ρ)}−GF√2VtbV∗ts{(a4+a10)ALLab(¯K,ρ)+(C3+C9)ALLcd(¯K,ρ)+(a6+a8)ASPab(¯K,ρ)+(C5+C7)ASPcd(¯K,ρ)+(a4−12a10)ALLef(¯K,ρ)+(C3−12C9)ALLgh(¯K,ρ)+(a6−12a8)ASPef(¯K,ρ)+(C5−12C7)ASPgh(¯K,ρ)},
A(¯B0d→¯K∗0π0)=GF2VubV∗us{a2ALLab(π,¯K∗)+C1ALLcd(π,¯K∗)}+GF2VtbV∗ts{(a4−12a10)[ALLab(¯K∗,π)+ALLef(¯K∗,π)]+(C3−12C9)[ALLcd(¯K∗,π)+ALLgh(¯K∗,π)]+32(a7−a9)ALLab(π,¯K∗)−32C8ALRcd(π,¯K∗)−32C10ALLcd(π,¯K∗)+(a6−12a8)ASPef(¯K∗,π)+(C5−12C7)[ASPcd(¯K∗,π)+ASPgh(¯K∗,π)]},
A(¯B0d→¯K0ρ0)=GF2VubV∗us{a2ALLab(ρ,¯K)+C1ALLcd(ρ,¯K)}+GF2VtbV∗ts{(a4−12a10)[ALLab(¯K,ρ)+ALLef(¯K,ρ)]+(C3−12C9)[ALLcd(¯K,ρ)+ALLgh(¯K,ρ)]+(a6−12a8)[ASPab(¯K,ρ)+ASPef(¯K,ρ)]+(C5−12C7)[ASPcd(¯K,ρ)+ASPgh(¯K,ρ)]−32(a7+a9)ALLab(ρ,¯K)−32C8ALRcd(ρ,¯K)−32C10ALLcd(ρ,¯K)},
A(¯B0d→¯K0ω)=GF2VubV∗us{a2ALLab(ω,¯K)+C1ALLcd(ω,¯K)}−GF2VtbV∗ts{(a4−12a10)[ALLab(¯K,ω)+ALLef(¯K,ω)]+(C3−12C9)[ALLcd(¯K,ω)+ALLgh(¯K,ω)]+(a6−12a8)[ASPab(¯K,ω)+ASPef(¯K,ω)]+(C5−12C7)[ASPcd(¯K,ω)+ASPgh(¯K,ω)]+(2a3+2a5+12a7+12a9)ALLab(ω,¯K)+(2C4+12C10)ALLcd(ω,¯K)+(2C6+12C8)ALRcd(ω,¯K)},
A(¯B0d→¯K0ϕ)=−GF√2VtbV∗ts{(a3+a4+a5−12a7−12a9−12a10)ALLab(ϕ,¯K)+(a4−12a10)ALLef(ϕ,¯K)+(a6−12a8)ASPef(ϕ,¯K)+(C3+C4−12C9−12C10)ALLcd(ϕ,¯K)+(C6−12C8)ALRcd(ϕ,¯K)+(C5−12C7)[ASPcd(ϕ,¯K)+ASPgh(ϕ,¯K)]+(C3−12C9)ALLgh(ϕ,¯K)},
A(¯B0d→K∗−K+)=GF√2VubV∗ud{a2ALLef(K,¯K∗)+C1ALLgh(K,¯K∗)}−GF√2VtbV∗td{(a3−a5−a7+a9)ALLef(K,¯K∗)+(C4+C10)ALLgh(K,¯K∗)+(C6+C8)ALRgh(K,¯K∗)+(a3−a5+12a7−12a9)ALLef(¯K∗,K)+(C4−12C10)ALLgh(¯K∗,K)+(C6−12C8)ALRgh(¯K∗,K)},
A(¯B0d→K−K∗+)=GF√2VubV∗ud{a2ALLef(K∗,¯K)+C1ALLgh(K∗,¯K)}−GF√2VtbV∗td{(a3−a5−a7+a9)ALLef(K∗,¯K)+(C4+C10)ALLgh(K∗,¯K)+(C6+C8)ALRgh(K∗,¯K)+(a3−a5+12a7−12a9)ALLef(¯K,K∗)+(C4−12C10)ALLgh(¯K,K∗)+(C6−12C8)ALRgh(¯K,K∗)}.
In shorthand,
ai={Ci+1NcCi+1,for odd i;Ci+1NcCi−1,for even i,
CmAkij(M1,M2)=Aki(Cm,M1,M2)+Akj(Cm,M1,M2),
where the explicit expressions of the amplitude building blocks
Aki(Cm,M1,M2) , including contributions from the B mesonic WFsϕB2 , are given in Appendix B. -
For the sake of simplification and convenience, shorthand is used for the amplitude building blocks.
ϕB1,B2=ϕB1,B2(x1,b1)e−SB,
ϕaP=ϕaP(x2)e−SP,
ϕp,tP=rPϕp,tP(x2)e−SP,
ϕvV=f∥VϕvV(x3)e−SV,
ϕt,sV=rVf⊥Vϕt,sV(x3)e−SV,
C=πCFN2cm4BfBfP,
where
rP=μP/mB , andrV=mV/mB . For the amplitude building blockAji(M1,M2) , the subscript i corresponds to the indices of Fig. 4, and the superscript j refers to the three possible Dirac structuresΓ1⊗Γ2 of the operator(ˉq1q2)Γ1(ˉq3q4)Γ2 , namelyj=LL for(V−A)⊗(V−A) ,j=LR for(V−A)⊗(V+A) , andj=SP for−2(S−P)⊗(S+P) . The explicit expressions ofAji(M1,M2) up to the order ofrP andrV are written as follows:ALLa(P,V)=C∫dx1dx3db1db3Hab(αVg,βVa,b1,b3)αs(tVa)Ci(tVa){ϕB1[ϕvV(1+x3)+(ϕtV+ϕsV)(ˉx3−x3)]−ϕB2[ϕvV−(ϕtV+ϕsV)x3]}St(x3), ALRa(P,V)=−ALLa(P,V),
ASPa(P,V)=C∫dx1dx3db1db3Hab(αVg,βVa,b1,b3)αs(tVa)Ci(tVa)2rP{ϕB1[−ϕvV+ϕtVx3−ϕsV(2+x3)]+ϕB2[ϕvV−ϕtV+ϕsV]}St(x3),
ALLa(V,P)=Cf∥V∫dx1dx2db1db2Hab(αPg,βPa,b1,b2)αs(tPa){ϕB1[ϕaP(1+x2)+(ϕpP+ϕtP)(ˉx2−x2)]−ϕB2[ϕaP−(ϕpP+ϕtP)x2]}Ci(tPa)St(x2),
ALRa(V,P)=ALLa(V,P),
ASPa(V,P)=0,
ALLb(P,V)=2C∫dx1dx3db1db3Hab(αVg,βVb,b3,b1)αs(tVb)Ci(tVb)St(x1)ϕB1ϕsV,
ALRb(P,V)=−ALLb(P,V),
ASPb(P,V)=−C∫dx1dx3db1db3Hab(αVg,βVb,b3,b1)αs(tVb)Ci(tVb)St(x1)2rP{ϕB1[ϕvVx1+2ϕsVˉx1]+2ϕB2ϕsVx1]},
ALLb(V,P)=2Cf∥V∫dx1dx2db1db2Hab(αPg,βPb,b2,b1)αs(tPb)Ci(tPb)St(x1)ϕB1ϕpP,
ALRb(V,P)=ALLb(V,P),
ASPb(V,P)=0,
ALLc(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVc,b1,b2)αs(tVc)Ci(tVc)St(x3)ϕaP{(ϕB1−ϕB2)ϕvV(ˉx2−x1)+ϕB1(ϕtV−ϕsV)x3}b1=b3,
ALRc(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVc,b1,b2)αs(tVc)Ci(tVc)St(x3)ϕaP{(ϕB1−ϕB2)[ϕvV(x1−ˉx2)+(ϕtV+ϕsV)x3]−ϕB1ϕvVx3}b1=b3,
ASPc(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVc,b1,b2)αs(tVc)Ci(tVc)St(x3){(ϕB1−ϕB2)(ϕpP+ϕtP)(ϕvV−ϕtV+ϕsV)(x1−ˉx2)−ϕB1(ϕpP−ϕtP)(ϕtV+ϕsV)x3}b1=b3,
ALLc(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPc,b1,b3)αs(tPc)Ci(tPc)St(x2)ϕvV{(ϕB1−ϕB2)ϕaP(ˉx3−x1)−ϕB1(ϕpP−ϕtP)x2}b1=b2,
ALRc(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPc,b1,b3)αs(tPc)Ci(tPc)St(x2)ϕvV{(ϕB1−ϕB2)[ϕaP(ˉx3−x1)−(ϕpP+ϕtP)x2]+ϕB1ϕaPx2}b1=b2,
ASPc(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPc,b1,b3)αs(tPc)Ci(tPc)St(x2){(ϕB1−ϕB2)(ϕaP+ϕpP−ϕtP)(ϕtV+ϕsV)(ˉx3−x1)−ϕB1(ϕpP+ϕtP)(ϕtV−ϕsV)x2}b1=b2,
ALLd(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVd,b1,b2)αs(tVd)Ci(tVd)St(x3)ϕap{(ϕB1−ϕB2)[ϕvV(x1−x2)+(ϕtV+ϕsV)x3]−ϕB1ϕvVx3}b1=b3,
ALRd(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVd,b1,b2)αs(tVd)Ci(tVd)St(x3)ϕap{(ϕB1−ϕB2)ϕvV(x2−x1)+ϕB1(ϕtV−ϕsV)x3}b1=b3,
ASPd(P,V)=C∫dx1dx2dx3db1db2Hcd(αVg,βVd,b1,b2)αs(tVd)Ci(tVd)St(x3){(ϕB1−ϕB2)(ϕpP−ϕtP)(ϕvV−ϕtV+ϕsV)(x2−x1)+ϕB1(ϕpP+ϕtP)(ϕtV+ϕsV)x3}b1=b3,
ALLd(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPd,b1,b3)αs(tPd)Ci(tPd)St(x2)ϕvV{(ϕB1−ϕB2)[ϕaP(x1−x3)+(ϕpP+ϕtP)x2]−ϕB1ϕaPx2}b1=b2,
ALRd(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPd,b1,b3)αs(tPd)Ci(tPd)St(x2)ϕvV{(ϕB1−ϕB2)ϕaP(x1−x3)+ϕB1(ϕpP−ϕtP)x2}b1=b2,
ASPd(V,P)=C∫dx1dx2dx3db1db3Hcd(αPg,βPd,b1,b3)αs(tPd)Ci(tPd)St(x2){(ϕB1−ϕB2)(ϕaP+ϕpP−ϕtP)(ϕtV−ϕsV)(x3−x1)−ϕB1(ϕpP+ϕtP)(ϕtV+ϕsV)x2}b1=b2,
ALLe(P,V)=C∫dx2dx3db2db3Hef(αVa,βVe,b2,b3)αs(tVe)Ci(tVe){2ϕpP[ϕtVx3+ϕsV(1+ˉx3)]−ϕaPϕvVˉx3}St(ˉx3),
ALRe(P,V)=−ALLe(P,V),
ASPe(P,V)=2C∫dx2dx3db2db3Hef(αVa,βVe,b2,b3)αs(tVe)Ci(tVe)St(ˉx3){ϕaP(ϕtV+ϕsV)ˉx3−2ϕpPϕvV},
ALLe(V,P)=−C∫dx2dx3db2db3Hef(αPa,βPe,b3,b2)αs(tPe)Ci(tPe){ϕaPϕvVˉx2+2ϕsV[ϕpP(1+ˉx2)+ϕtPx2]}St(ˉx2),
ALRe(V,P)=−ALLe(V,P),
ASPe(V,P)=2C∫dx2dx3db2db3Hef(αPa,βPe,b3,b2)αs(tPe)Ci(tPe)St(ˉx2){2ϕaPϕsV+ϕvV(ϕpP+ϕtP)ˉx2},
ALLf(P,V)=C∫dx2dx3db2db3Hef(αVa,βVf,b3,b2)αs(tVf)Ci(tVf){ϕaPϕvVx2−2ϕsV[ϕpP(1+x2)−ϕtPˉx2]}St(x2),
ALRf(P,V)=−ALLf(P,V),
ASPf(P,V)=2C∫dx2dx3db2db3Hef(αVa,βVf,b3,b2)αs(tVf)Ci(tVf)St(x2){2ϕaPϕsV−(ϕpP−ϕtP)ϕvVx2},
ALLf(V,P)=C∫dx2dx3db2db3Hef(αPa,βPf,b2,b3)αs(tPf)Ci(tPf){ϕaPϕvVx3−2ϕpP[ϕtVˉx3−ϕsV(1+x3)]}St(x3),
ALRf(V,P)=−ALLf(V,P),
ASPf(V,P)=2C∫dx2dx3db2db3Hef(αPa,βPf,b2,b3)αs(tPf)Ci(tPf)St(x3){2ϕpPϕvV−ϕaP(ϕtV−ϕsV)x3},
ALLg(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVg,b1,b2)αs(tVg)Ci(tVg){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx3−x2)−ϕaPϕvV(x1+x2)+(ϕpPϕsV−ϕtPϕtV)(x2+ˉx3−2ˉx1)+4ϕpPϕsV]+ϕB2[(ϕpP−ϕtP)(ϕtV+ϕsV)(x3−x1)−2(ϕpP−ϕtP)ϕsV]}b2=b3,
ALRg(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVg,b1,b2)αs(tVg)Ci(tVg){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx3−x2)+ϕaPϕvV(x1+ˉx3)−(ϕpPϕsV−ϕtPϕtV)(x2+ˉx3−2ˉx1)−4ϕpPϕsV]+ϕB2[(ϕpP+ϕtP)(ϕtV−ϕsV)(x3−x1)−2ϕpP(ϕtV−ϕsV)−ϕaPϕvV(x1+ˉx3)]}b2=b3,
ASPg(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVg,b1,b2)αs(tVg)Ci(tVg){(ϕB1−ϕB2)[ϕaP(ϕtV−ϕsV)(x3−x1)−(ϕpP+ϕtP)ϕvV]+ϕB1[ϕaP(ϕtV−ϕsV)+(ϕpP+ϕtP)ϕvV(x2−ˉx1)]}b2=b3,
ALLg(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPg,b1,b3)αs(tPg)Ci(tPg){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx2−x3)−ϕaPϕvV(x1+x3)−(ϕpPϕsV−ϕtPϕtV)(ˉx2+x3−2ˉx1)−4ϕpPϕsV]+ϕB2[(ϕpP−ϕtP)(ϕtV+ϕsV)(x3−ˉx1)+2ϕpP(ϕtV+ϕsV)+ϕaPϕvV(x1+x3)]}b2=b3,
ALRg(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPg,b1,b3)αs(tPg)Ci(tPg){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx2−x3)+ϕaPϕvV(x1+ˉx2)+(ϕpPϕsV−ϕtPϕtV)(ˉx2+x3−2ˉx1)+4ϕpPϕsV]+ϕB2[(ϕpP+ϕtP)(ϕtV−ϕsV)(x3−ˉx1)−2(ϕpP+ϕtP)ϕsV]}b2=b3,
ASPg(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPg,b1,b3)αs(tPg)Ci(tPg){(ϕB1−ϕB2)[ϕaP(ϕtV+ϕsV)(ˉx1−x3)−(ϕpP−ϕtP)ϕvV]+ϕB1[ϕaP(ϕtV+ϕsV)+(ϕpP−ϕtP)ϕvV(x1−x2)]}b2=b3,
ALLh(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVh,b1,b2)αs(tVh)Ci(tVh){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx3−x2)+ϕaPϕvV(ˉx3−x1)−(ϕpPϕsV−ϕtPϕtV)(x2+ˉx3−2x1)]+ϕB2[ϕaPϕvV+(ϕpP+ϕtP)(ϕtV−ϕsV)](x1−ˉx3)}b2=b3,
ALRh(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVh,b1,b2)αs(tVh)Ci(tVh){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx3−x2)+ϕaPϕvV(x1−x2)+(ϕpPϕsV−ϕtPϕtV)(x2+ˉx3−2x1)]+ϕB2(ϕpP−ϕtP)(ϕtV+ϕsV)(x1−ˉx3)}b2=b3,
ASPh(P,V)=C∫dx1dx2dx3db1db2Hgh(αVa,βVh,b1,b2)αs(tVh)Ci(tVh){(ϕB1−ϕB2)(ϕpP+ϕtP)ϕvV(x1−x2)+ϕB1ϕaP(ϕtV−ϕsV)(ˉx3−x1)}b2=b3,
ALLh(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPh,b1,b3)αs(tPh)Ci(tPh){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx2−x3)+ϕaPϕvV(ˉx2−x1)+(ϕpPϕsV−ϕtPϕtV)(ˉx2+x3−2x1)]+ϕB2(ϕpP+ϕtP)(ϕtV−ϕsV)(x3−x1)}b2=b3,
ALRh(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPh,b1,b3)αs(tPh)Ci(tPh){ϕB1[(ϕpPϕtV−ϕtPϕsV)(ˉx2−x3)+ϕaPϕvV(x1−x3)−(ϕpPϕsV−ϕtPϕtV)(ˉx2+x3−2x1)]+ϕB2[ϕaPϕvV+(ϕpP−ϕtP)(ϕtV+ϕsV)](x3−x1)}b2=b3,
ASPh(V,P)=C∫dx1dx2dx3db1db3Hgh(αPa,βPh,b1,b3)αs(tPh)Ci(tPh){(ϕB1−ϕB2)(ϕpP−ϕtP)ϕvV(x1−ˉx2)+ϕB1ϕaP(ϕtV+ϕsV)(x3−x1)}b2=b3,
αVg=m2Bx1x3,
αPg=m2Bx1x2,
αVa=m2Bx2ˉx3,
αPa=m2Bˉx2x3,
βVa=m2Bx3,
βPa=m2Bx2,
βVb=βPb=m2Bx1,
βVc=m2Bx3(x1−ˉx2),
βPc=m2Bx2(x1−ˉx3),
βVd=m2Bx3(x1−x2),
βPd=m2Bx2(x1−x3),
βVe=m2Bˉx3,
βPe=m2Bˉx2,
βVf=m2Bx2,
βPf=m2Bx3,
βVg=αVa−m2Bˉx1(x2+ˉx3),
βPg=αPa−m2Bˉx1(ˉx2+x3),
βVh=αVa−m2Bx1(x2+ˉx3),
βPh=αPa−m2Bx1(ˉx2+x3),
tVa,b=max(αVg,βVa,b,b1,b3),
tPa,b=max(αPg,βPa,b,b1,b2),
tic,d=max(αig,βic,d,b2,b3),
tie,f=max(αia,βie,f,b2,b3),
tig,h=max(αia,βig,h,b1,b2),
Hab(α,β,bi,bj)=bibjK0(bi√α){θ(bi−bj)K0(bi√β)I0(bj√β)+(bi↔bj)}, NcHcd(α,β,b1,bi)=b1bi{θ(b1−b2)K0(b1√α)I0(bi√α)+(b1↔bi)}{θ(β)K0(bi√β)+iπ2θ(−β)[J0(bi√−β)+iY0(bi√−β)]},
Hef(α,β,bi,bj)=−π24bibj{J0(bi√α)+iY0(bi√α)}{θ(bi−bj)[J0(bi√β)+iY0(bi√β)]J0(bj√β)+(bi↔bj)},
NcHgh(α,β,b1,bi)=b1bi{iπ2θ(β)[J0(b1√β)+iY0(b1√β)]+θ(−β)K0(b1√−β)}iπ2{θ(b1−bi)[J0(b1√α)+iY0(b1√α)]J0(bi√α)+(b1↔bi)}.
Reinvestigating B → PV decays by including contributions from ϕB2 with the perturbative QCD approach
- Received Date: 2022-02-25
- Available Online: 2022-08-15
Abstract: Considering the B mesonic wave function