We re-derive exactly the transverse Ward–Takahashi relation for the vector vertex in momentum space. The result shows that this transverse Ward–Takahashi relation in momentum space involves a perturbative correction...We re-derive exactly the transverse Ward–Takahashi relation for the vector vertex in momentum space. The result shows that this transverse Ward–Takahashi relation in momentum space involves a perturbative correction term. We demonstrate explicitly that this transverse Ward–Takahashi relation is satisfied indeed at one-loop order.展开更多
In the two-quark model supposition for the meson ao（1450）, which can be viewed as either the first excited state （scenario I） or the lowest lying state （scenario II）, the branching ratios and the direct CP-viola...In the two-quark model supposition for the meson ao（1450）, which can be viewed as either the first excited state （scenario I） or the lowest lying state （scenario II）, the branching ratios and the direct CP-violating asymmetries for decays B→a0（1450）ρ（ω） are studied by employing the perturbative QCD factorization approach. We find the following results： （a） For the decays B- B→a0（1450）ρ- andB→a0^＋（1450）ρ^-, their branching ratios have large difference between two scenarios. Although their branching ratios are larger than other considered decay modes, their direct CP-violating asymmetries in both scenarios are small. （b） For the decays B-→a0^-（1450）ρ0 and B0→ a0（1450）ρ＋, a0^0（1450）ρ0, a00 （1450）w, their branching ratios are dose to each other between two scenarios, respectively. （c） Comparing with the decays a0^0（1450）ρ0,π0ρ0 π0π0, the decay B-→a0^-（1450）ρ0 receives a larger branching ratio in each scenario, which is sensitive to the variation of the Cabibbo-Kobayashi-Maskawa angle α.展开更多
Using a new perturbative expansion method in Quantum Chromodynamics with a non-perturbative gluon background, the gluon propagator is calculated up to the one-loop level, and renormalized in the modified minimal subtr...Using a new perturbative expansion method in Quantum Chromodynamics with a non-perturbative gluon background, the gluon propagator is calculated up to the one-loop level, and renormalized in the modified minimal subtraction scheme. The resultant renormalization constants of the quantum gluon field and the gauge parameter receive a non-perturbative contribution coming from the gluon condensate <FF> besides the usual perturbative one, respectively.展开更多
The scaling behaviors of the nucleon resonance transition amplitudes from perturbative QCD (PQCD) are utilized to parametrize the amplitudes of the first negative-parity nucleon resonance . Our analysis indicates that...The scaling behaviors of the nucleon resonance transition amplitudes from perturbative QCD (PQCD) are utilized to parametrize the amplitudes of the first negative-parity nucleon resonance . Our analysis indicates that the constraints of the transition amplitude for the resonance at the limit by QCD sum rule calculations are not applicable at a moderate range of compared with the present available data if the contribution of is dominant in the limit.展开更多
In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar mes...In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.展开更多
Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the l...Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the logarithmic branch is given. Using the new type Baecklund transformation, many exact solutions are obtained.展开更多
The quantum chromodynamics(QCD) coupling αs is the most important parameter for achieving precise QCD predictions. By using the well measured effective coupling α_(s)^(g)1)(Q) defined from the Bjorken sum rules as a...The quantum chromodynamics(QCD) coupling αs is the most important parameter for achieving precise QCD predictions. By using the well measured effective coupling α_(s)^(g)1)(Q) defined from the Bjorken sum rules as a basis, we suggest a novel self-consistency way to fix the αs at all scales: The QCD light-front holographic model is adopted for its infrared behavior, and the fixed-order p QCD prediction under the principle of maximum conformality(PMC) is used for its high-energy behavior. Using the PMC scheme-and-scale independent perturbative series,and by transforming it into the one under the physical V scheme, we observe that a precise αs running behavior in both the perturbative and nonperturbative domains with a smooth transition from small to large scales can be achieved.展开更多
We compare the results of some perturbative quantum dissipation approaches to the exact linear absorption of two state systems. The considered approximate methods are the so-called complete second-order quantum dissip...We compare the results of some perturbative quantum dissipation approaches to the exact linear absorption of two state systems. The considered approximate methods are the so-called complete second-order quantum dissipation theories, in either the chronological ordering prescription or the correlated driving-dissipation form. Analytical results can be derived for the linear absorption of two-state systems. Assessments on their applicability are then made by comparison to the exact results.展开更多
We extend our previous work of a classical over-barrier ionization （COBI） model to calculate the single ionization cross sections of noble gases ranging from He to Xe at strong perturbative energies. The calculation...We extend our previous work of a classical over-barrier ionization （COBI） model to calculate the single ionization cross sections of noble gases ranging from He to Xe at strong perturbative energies. The calculation results are in good agreement with extensive experimental data. The scaling law of single ion-atom impact ionization cross sections of noble gases on projectile charge q and energy E, also on target ionization energy I is drawn from the model.展开更多
From the point of view of evolution equations with soliton solutions,we present a general way for the study of the shockwave of one-dimensional Burgers equation under the action of perturbations.Apart from the damping...From the point of view of evolution equations with soliton solutions,we present a general way for the study of the shockwave of one-dimensional Burgers equation under the action of perturbations.Apart from the damping case which needs a somewhat special treatment,we formulate the effects induced by other general perturbations unifyingly.展开更多
The local approach to construct master equation for a composite open system with a weak internal coupling is simple and seems reasonable. However, it is thermodynamic consistent only when the subsystems are resonantly...The local approach to construct master equation for a composite open system with a weak internal coupling is simple and seems reasonable. However, it is thermodynamic consistent only when the subsystems are resonantly coupled. Efforts are being made to understand the inconsistency and test the validity of the local master equation. We present a perturbative method to solve the steady-state solutions of linear local master equations, which are demonstrated by two simple models. The solving process shows the stationary state as the result of competition between incoherent operations and the unitary creating quantum coherence, and consequently relate quantum coherence with thermodynamic consistency.展开更多
We study perturbativeness of chiral nuclear forces in the 3P0 channel. In previous works, the focus has been on the one-pion exchange, and the applicable window of perturbative pion exchanges has been shown to span fr...We study perturbativeness of chiral nuclear forces in the 3P0 channel. In previous works, the focus has been on the one-pion exchange, and the applicable window of perturbative pion exchanges has been shown to span from the threshold to center-of-mass momentum k■180 MeV. We will examine,instead, whether the cancellation of short-and long-range parts can sufficiently soften the 3P0 chiral force to make it more amenable to perturbation theory. The result is encouraging, as the combined 3P0 force is shown to be perturbative up to k■280 MeV, covering many nuclear-structure calculations.展开更多
Although tetraquarks and pentaquarks[1]were predicted along with the quark model in 1964,more than half a century passed,multiquark-like states observed in experiments are still rare.Among these states,the structure o...Although tetraquarks and pentaquarks[1]were predicted along with the quark model in 1964,more than half a century passed,multiquark-like states observed in experiments are still rare.Among these states,the structure of hardly any was identified;whether they are multiquarks,molecules of hadrons,or other possible species of resonances are still under debate(for a review,see e.g.,Refs.[2,3]).展开更多
The annihilation type diagrams are difficult to calculate in any kind of model or method. Encouraged by the successful calculation of pure annihilation type B decays in the perturbative QCD factorization approach, we ...The annihilation type diagrams are difficult to calculate in any kind of model or method. Encouraged by the successful calculation of pure annihilation type B decays in the perturbative QCD factorization approach, we calculate the pure annihilation type D→ PP（V） decays in the perturbative QCD approach based on the kw factorization. Although the expansion parameter 1lind is not very small, our leading order numerical results agree with the existing experimental data for most channels. We expect more accurate observation from experiments, which can help us learn about the dynamics of D meson weak decays.展开更多
In this paper,we calculated the B →（J/ψ,ηc） K decays in the perturbative QCD（pQCD） factorization approach with the inclusion of the partial next-to-leading order（NLO） contributions. With the inclusion of the ...In this paper,we calculated the B →（J/ψ,ηc） K decays in the perturbative QCD（pQCD） factorization approach with the inclusion of the partial next-to-leading order（NLO） contributions. With the inclusion of the significant enhancement from the NLO vertex corrections,the NLO pQCD predictions for the branching ratios agree with the data within 2σ errors：Br（B0 → J/ψK0） = 5.2-＋32..58×10-4,Br（B＋ → J/ψK＋） = 5.6-＋32..79×10-4,Br（B0 →ηcK0） = 5.5-＋22..30 × 10-4,Br（B＋ →ηcK＋） = 5.9-＋22..51 × 10-4.展开更多
We present a phenomenological analysis of the space- and time-like charged kaon electromagnetic form factors in factorized perturbative QCD （pQCD） by employing an analytic model for αs （Q2 ） and an infrared （IR...We present a phenomenological analysis of the space- and time-like charged kaon electromagnetic form factors in factorized perturbative QCD （pQCD） by employing an analytic model for αs （Q2 ） and an infrared （IR） finite gluon propagator. In the space-like region, due to the lack of available experimental data above Q2 ～ 0.2 GeV2 , we only give our results for intermediate energies and make no comparison. In the time-like region, our results agree reasonably well with the available experimental data at moderate energies, including the CLEO data and the J/ψ result.展开更多
The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ （0） and the branching ratio IBr（Bc → Bsπ） ar...The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ （0） and the branching ratio IBr（Bc → Bsπ） are sensitive to the model of the Bs meson wave functions. With appropriate inputs, our estimate on 23r（Bc → Bsπ） is comparable with the recent LHCb measurement. A clear signal of Bc → Bsπ decay should be easily observed at the Large Hadron Collider.展开更多
Considering the B mesonic wave function φ_(B2),B→PV decays are re studied in the leading order for three scenarios using the perturbative QCD approach within the standard model,where P=π and K,and V denotes the gro...Considering the B mesonic wave function φ_(B2),B→PV decays are re studied in the leading order for three scenarios using the perturbative QCD approach within the standard model,where P=π and K,and V denotes the ground SU(3) vector mesons.It is found that contributions from φ_(B2) can enhance most branching ratios and are helpful for improving the overall consistency of branching ratios between the updated calculations and available data,although there are still several discrepancies between the experimental and theoretical results.展开更多
The principle of maximum conformality(PMC)provides a systematic approach to solve the conventional renormalization scheme and scale ambiguities.Scale-fixed predictions of physical observables using the PMC are indepen...The principle of maximum conformality(PMC)provides a systematic approach to solve the conventional renormalization scheme and scale ambiguities.Scale-fixed predictions of physical observables using the PMC are independent of the choice of renormalization scheme–a key requirement for renormalization group invariance.In this paper,we derive new degeneracy relations based on the renormalization group equations that involve both the usualβ-function and the quark mass anomalous dimensionγm-function.These new degeneracy relations enable improved PMC scale-setting procedures for correct magnitudes of the strong coupling constant and MS¯-running quark mass to be determined simultaneously.By using these improved PMC scale-setting procedures,the renormalization scale dependence of the MS¯-on-shell quark mass relation can be eliminated systematically.Consequently,the top-quark on-shell(or MS¯)mass can be determined without conventional renormalization scale ambiguity.Taking the top-quark MS¯mass m¯t(m¯t)=162.5+2.1−1.5 GeV as the input,we obtain Mt≃172.41+2.21−1.57 GeV.Here,the uncertainties arise from errors combined with those fromΔαs(MZ)and the approximate uncertainty resulting from the uncalculated five-loop terms predicted through the Padéapproximation approach.展开更多
In this study,we investigate quasi-two-body B_((s))→K^(*)γ→Kπγ decays in the perturbative QCD approach.Two-meson distribution amplitudes are introduced to describe the final state interactions of the Kπpair,whic...In this study,we investigate quasi-two-body B_((s))→K^(*)γ→Kπγ decays in the perturbative QCD approach.Two-meson distribution amplitudes are introduced to describe the final state interactions of the Kπpair,which involve time-like form factors and Gegenbauer polynomials.We calculate the CP averaged branching ratios of the B_((s))→K^(*)γ→Kπγ decays.Our results are in agreement with newly updated data measured by Belle Ⅱ.This suggests that it is more appropriate to analyze these quasi-two-body B decays in the three-body framework than the two-body framework.We also predict direct CP asymmetries for the considered decay modes and find that A_CP(B_(u,d)→K^(*)γ→Kπγ) is small and less than 1% in magnitude,whereas A_CP(B_(s)→K^(*)γ→Kπγ)is larger and can reach a few percent.Our predictions can be tested in future B meson experiments.展开更多
文摘We re-derive exactly the transverse Ward–Takahashi relation for the vector vertex in momentum space. The result shows that this transverse Ward–Takahashi relation in momentum space involves a perturbative correction term. We demonstrate explicitly that this transverse Ward–Takahashi relation is satisfied indeed at one-loop order.
基金Supported by National Natural Science Foundation of China under Grant No.11047158by Foundation of Henan University of Technology under Grant No.2009BS038
文摘In the two-quark model supposition for the meson ao（1450）, which can be viewed as either the first excited state （scenario I） or the lowest lying state （scenario II）, the branching ratios and the direct CP-violating asymmetries for decays B→a0（1450）ρ（ω） are studied by employing the perturbative QCD factorization approach. We find the following results： （a） For the decays B- B→a0（1450）ρ- andB→a0^＋（1450）ρ^-, their branching ratios have large difference between two scenarios. Although their branching ratios are larger than other considered decay modes, their direct CP-violating asymmetries in both scenarios are small. （b） For the decays B-→a0^-（1450）ρ0 and B0→ a0（1450）ρ＋, a0^0（1450）ρ0, a00 （1450）w, their branching ratios are dose to each other between two scenarios, respectively. （c） Comparing with the decays a0^0（1450）ρ0,π0ρ0 π0π0, the decay B-→a0^-（1450）ρ0 receives a larger branching ratio in each scenario, which is sensitive to the variation of the Cabibbo-Kobayashi-Maskawa angle α.
文摘Using a new perturbative expansion method in Quantum Chromodynamics with a non-perturbative gluon background, the gluon propagator is calculated up to the one-loop level, and renormalized in the modified minimal subtraction scheme. The resultant renormalization constants of the quantum gluon field and the gauge parameter receive a non-perturbative contribution coming from the gluon condensate <FF> besides the usual perturbative one, respectively.
文摘The scaling behaviors of the nucleon resonance transition amplitudes from perturbative QCD (PQCD) are utilized to parametrize the amplitudes of the first negative-parity nucleon resonance . Our analysis indicates that the constraints of the transition amplitude for the resonance at the limit by QCD sum rule calculations are not applicable at a moderate range of compared with the present available data if the contribution of is dominant in the limit.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10575052, 10605012, and 10735080
文摘In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.
文摘Using the standard Painlevé analysis and the perturbative method, the Painlevé test for the logarithmic branch is investigated. Nine arbitrary functions are obtained and the Baecklund transformation of the logarithmic branch is given. Using the new type Baecklund transformation, many exact solutions are obtained.
基金supported in part by the Chongqing Graduate Research and Innovation Foundation (Grant Nos. CYB21045 and ydstd1912)the National Natural Science Foundation of China (Grant Nos. 11905056, 12175025, and 12147102)the Fundamental Research Funds for the Central Universities (Grant No. 2020CQJQYZ003)。
文摘The quantum chromodynamics(QCD) coupling αs is the most important parameter for achieving precise QCD predictions. By using the well measured effective coupling α_(s)^(g)1)(Q) defined from the Bjorken sum rules as a basis, we suggest a novel self-consistency way to fix the αs at all scales: The QCD light-front holographic model is adopted for its infrared behavior, and the fixed-order p QCD prediction under the principle of maximum conformality(PMC) is used for its high-energy behavior. Using the PMC scheme-and-scale independent perturbative series,and by transforming it into the one under the physical V scheme, we observe that a precise αs running behavior in both the perturbative and nonperturbative domains with a smooth transition from small to large scales can be achieved.
文摘We compare the results of some perturbative quantum dissipation approaches to the exact linear absorption of two state systems. The considered approximate methods are the so-called complete second-order quantum dissipation theories, in either the chronological ordering prescription or the correlated driving-dissipation form. Analytical results can be derived for the linear absorption of two-state systems. Assessments on their applicability are then made by comparison to the exact results.
基金Project supported by the National Natural Science Foundation of China(Grants Nos.11174116,and 11175075)
文摘We extend our previous work of a classical over-barrier ionization （COBI） model to calculate the single ionization cross sections of noble gases ranging from He to Xe at strong perturbative energies. The calculation results are in good agreement with extensive experimental data. The scaling law of single ion-atom impact ionization cross sections of noble gases on projectile charge q and energy E, also on target ionization energy I is drawn from the model.
文摘From the point of view of evolution equations with soliton solutions,we present a general way for the study of the shockwave of one-dimensional Burgers equation under the action of perturbations.Apart from the damping case which needs a somewhat special treatment,we formulate the effects induced by other general perturbations unifyingly.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11675119,11575125,and 11105097
文摘The local approach to construct master equation for a composite open system with a weak internal coupling is simple and seems reasonable. However, it is thermodynamic consistent only when the subsystems are resonantly coupled. Efforts are being made to understand the inconsistency and test the validity of the local master equation. We present a perturbative method to solve the steady-state solutions of linear local master equations, which are demonstrated by two simple models. The solving process shows the stationary state as the result of competition between incoherent operations and the unitary creating quantum coherence, and consequently relate quantum coherence with thermodynamic consistency.
基金supported in part by the National Natural Science Foundation of China (NSFC) under Grant Nos.11775148 and 11735003。
文摘We study perturbativeness of chiral nuclear forces in the 3P0 channel. In previous works, the focus has been on the one-pion exchange, and the applicable window of perturbative pion exchanges has been shown to span from the threshold to center-of-mass momentum k■180 MeV. We will examine,instead, whether the cancellation of short-and long-range parts can sufficiently soften the 3P0 chiral force to make it more amenable to perturbation theory. The result is encouraging, as the combined 3P0 force is shown to be perturbative up to k■280 MeV, covering many nuclear-structure calculations.
基金supported in part by the National Natural Science Foundation of China(12375079,12325503,11975029,11965006,and 11875071)the National Key Research and Development Program of China(2020YFA0406400)+2 种基金the Guizhou Provincial Science and Technology Project(QKH-Basic-ZK[2021]YB319)the High-performance Computing Platform of Peking Universitysupported by the Natural Science Foundation of Chongqing(CSTB2023 NSCQ-MSX0132)。
文摘Although tetraquarks and pentaquarks[1]were predicted along with the quark model in 1964,more than half a century passed,multiquark-like states observed in experiments are still rare.Among these states,the structure of hardly any was identified;whether they are multiquarks,molecules of hadrons,or other possible species of resonances are still under debate(for a review,see e.g.,Refs.[2,3]).
基金Supported by National Science Foundation of China(11228512,11235005,11075168)
文摘The annihilation type diagrams are difficult to calculate in any kind of model or method. Encouraged by the successful calculation of pure annihilation type B decays in the perturbative QCD factorization approach, we calculate the pure annihilation type D→ PP（V） decays in the perturbative QCD approach based on the kw factorization. Although the expansion parameter 1lind is not very small, our leading order numerical results agree with the existing experimental data for most channels. We expect more accurate observation from experiments, which can help us learn about the dynamics of D meson weak decays.
基金Supported by National Natural Science Foundation of China (10605012,10735080)Project on Graduate Students' Education and Innovation of Jiangsu Province (CX09B 297Z)
文摘In this paper,we calculated the B →（J/ψ,ηc） K decays in the perturbative QCD（pQCD） factorization approach with the inclusion of the partial next-to-leading order（NLO） contributions. With the inclusion of the significant enhancement from the NLO vertex corrections,the NLO pQCD predictions for the branching ratios agree with the data within 2σ errors：Br（B0 → J/ψK0） = 5.2-＋32..58×10-4,Br（B＋ → J/ψK＋） = 5.6-＋32..79×10-4,Br（B0 →ηcK0） = 5.5-＋22..30 × 10-4,Br（B＋ →ηcK＋） = 5.9-＋22..51 × 10-4.
基金Supported by National Natural Science Foundation of China (10735080, 11075059)
文摘We present a phenomenological analysis of the space- and time-like charged kaon electromagnetic form factors in factorized perturbative QCD （pQCD） by employing an analytic model for αs （Q2 ） and an infrared （IR） finite gluon propagator. In the space-like region, due to the lack of available experimental data above Q2 ～ 0.2 GeV2 , we only give our results for intermediate energies and make no comparison. In the time-like region, our results agree reasonably well with the available experimental data at moderate energies, including the CLEO data and the J/ψ result.
基金supported by the National Natural Science Foundation of China(Grant Nos.11147008,U1232101 and 11275057)
文摘The Bc → Bsπ decay is studied with the perturbative QCD approach. Three types of wave functions for Bs meson are considered. The transition form factor F0Bc → Bsπ （0） and the branching ratio IBr（Bc → Bsπ） are sensitive to the model of the Bs meson wave functions. With appropriate inputs, our estimate on 23r（Bc → Bsπ） is comparable with the recent LHCb measurement. A clear signal of Bc → Bsπ decay should be easily observed at the Large Hadron Collider.
基金Supported by the National Natural Science Foundation of China (11705047,U1632109,11875122)the Natural Science Foundation of Henan Province(222300420479)+1 种基金the Excellent Youth Foundation of Henan Province (212300410010)the Youth Talent Support Program of Henan Province (ZYQR201912178)。
文摘Considering the B mesonic wave function φ_(B2),B→PV decays are re studied in the leading order for three scenarios using the perturbative QCD approach within the standard model,where P=π and K,and V denotes the ground SU(3) vector mesons.It is found that contributions from φ_(B2) can enhance most branching ratios and are helpful for improving the overall consistency of branching ratios between the updated calculations and available data,although there are still several discrepancies between the experimental and theoretical results.
基金Supported in part by the National Natural Science Foundation of China(12247129,12175025,12347101)the Graduate Research and Innovation Foundation of Chongqing,China(ydstd1912)。
文摘The principle of maximum conformality(PMC)provides a systematic approach to solve the conventional renormalization scheme and scale ambiguities.Scale-fixed predictions of physical observables using the PMC are independent of the choice of renormalization scheme–a key requirement for renormalization group invariance.In this paper,we derive new degeneracy relations based on the renormalization group equations that involve both the usualβ-function and the quark mass anomalous dimensionγm-function.These new degeneracy relations enable improved PMC scale-setting procedures for correct magnitudes of the strong coupling constant and MS¯-running quark mass to be determined simultaneously.By using these improved PMC scale-setting procedures,the renormalization scale dependence of the MS¯-on-shell quark mass relation can be eliminated systematically.Consequently,the top-quark on-shell(or MS¯)mass can be determined without conventional renormalization scale ambiguity.Taking the top-quark MS¯mass m¯t(m¯t)=162.5+2.1−1.5 GeV as the input,we obtain Mt≃172.41+2.21−1.57 GeV.Here,the uncertainties arise from errors combined with those fromΔαs(MZ)and the approximate uncertainty resulting from the uncalculated five-loop terms predicted through the Padéapproximation approach.
基金Supported in part by the National Natural Science Foundation of China under(11347030)the Program of Science and Technology Innovation Talents in Universities of Henan Province(14HASTIT037)。
文摘In this study,we investigate quasi-two-body B_((s))→K^(*)γ→Kπγ decays in the perturbative QCD approach.Two-meson distribution amplitudes are introduced to describe the final state interactions of the Kπpair,which involve time-like form factors and Gegenbauer polynomials.We calculate the CP averaged branching ratios of the B_((s))→K^(*)γ→Kπγ decays.Our results are in agreement with newly updated data measured by Belle Ⅱ.This suggests that it is more appropriate to analyze these quasi-two-body B decays in the three-body framework than the two-body framework.We also predict direct CP asymmetries for the considered decay modes and find that A_CP(B_(u,d)→K^(*)γ→Kπγ) is small and less than 1% in magnitude,whereas A_CP(B_(s)→K^(*)γ→Kπγ)is larger and can reach a few percent.Our predictions can be tested in future B meson experiments.
