期刊：
Journal of High Energy Physics,2010年2010(4):1-16 ISSN：1029-8479
通讯作者：
Li, Xin-Qiang
作者机构：
[Chang, Qin; Li, Xin-Qiang] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China.;[Yang, Ya-Dong; Chang, Qin] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;[Li, Xin-Qiang] Rhein Westfal TH Aachen, Inst Theoret Phys E, D-52056 Aachen, Germany.;[Yang, Ya-Dong] Huazhong Normal Univ, Minist Educ, Key Lab Quark & Lepton Phys, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Li, Xin-Qiang] H;Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China.
关键词：
Rare Decays;Beyond Standard Model;B-Physics
摘要：
Motivated by the observed forward-backward asymmetry in B → K*ℓ
+
ℓ
− decay, we perform a detailed analysis of this decay mode within a family non-universal Z′ model. With the related coupling
$$ Z' - \bar sb $$
constrained by
$$ {B_s} - {\bar B_s} $$
mixing, B → πK and B → X
s
μ
+
μ
− decays, we look for further constraint on the couplings Z′ − μ
+
μ
− from
$$ {A_{FB}}{\left( {B \to {K^*}{\mu^{+} }{\mu^{-} }} \right)_{0{\text{Ge}}{{\text{V}}^2} \leqslant {q^2} \leqslant 2{\text{Ge}}{{\text{V}}^2}}} $$
and get numerically
$$ B_{\mu \mu }^{L,R} \sim \mathcal{O}\left( {{{10}^{ - 2}}} \right) $$
. Moreover, we find that the relations
$$ B_{\mu \mu }^L < B_{\mu \mu }^R $$
and
$$ B_{\mu \mu }^L + B_{\mu \mu }^R < 0 $$
, with a small negative phase ϕ
s
L
, are crucial to moderate the discrepancy for A
FB
(B → K*μ
+
μ
−) between the SM prediction and the experimental data. Numerically, comparing with the SM prediction, we find that
$$ {A_{FB}}{\left( {B \to {K^*}{\mu^{+} }{\mu^{-} }} \right)_{0{\text{Ge}}{{\text{V}}^2} \leqslant {q^2} \leqslant 2{\text{Ge}}{{\text{V}}^2}}} $$
could be enhanced about 80% and 50% by Z′ contribution at most in scenarios S1 and S2, corresponding to the two fitted results of ϕ
s
by UTfit collaboration, respectively. However, the results are still about 1.5σ lower than the experimental measurement.
期刊：
Journal of High Energy Physics,2009年2009(5) ISSN：1029-8479
通讯作者：
Yang, Ya-Dong
作者机构：
[Yang, Ya-Dong; Chang, Qin] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;[Chang, Qin] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China.;[Li, Xin-Qiang] Rhein Westfal TH Aachen, Inst Theoret Phys E, D-52056 Aachen, Germany.
通讯机构：
[Yang, Ya-Dong] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.
关键词：
B-physics;Beyond standard model;CP violation;Rare decays
摘要：
Motivated by the large difference between the direct CP asymmetries A(CP)(B- -> pi K-0(-)) and A(CP) ((B) over bar (0) -> pi K-+(-)), we combine the up-to-date experimental information on B -> pi K, pi K* and rho K decays to pursue possible solutions with the nonuniversal Z' model. Detailed analyses of the relative impacts of different types of couplings are presented in four specific cases. Numerically, we find that the new coupling parameters, xi(LL) and xi(LR) with a common nontrivial new weak phase phi(L) similar to -86 degrees, which are relevant to the Z' contributions to the electroweak penguin sector Delta C-9 and Delta C-7, are crucial to the observed "pi K puzzle". Furthermore, they are found to be definitely unequal and opposite in sign. We also find that A(CP)(B- -> rho(0) K-) can put a strong constraint on the new Z' couplings, which implies the Z' contributions to the coefficient of QCD penguins operator O-3 involving the parameter zeta(LL) required.
期刊：
Journal of High Energy Physics,2008年2008(09):038- ISSN：1029-8479
通讯作者：
Yang, Y.-D.
作者机构：
Institute of Particle Physics, Huazhong Normal University, Wuhan, Hubei 430079, P.R. China;Department of Physics, Henan Normal University, Xinxiang, Henan 453007, P.R. China;Institut für Theoretische Physik E, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, D-52056, Aachen, Germany
通讯机构：
Institute of Particle Physics, Huazhong Normal University, China
关键词：
B-physics;Beyond standard model;CP violation;Rare decays
期刊：
Journal of High Energy Physics,2008年(9) ISSN：1029-8479
通讯作者：
Yang, Ya-Dong
作者机构：
[Yang, Ya-Dong; Chang, Qin] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;[Chang, Qin] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China.;[Li, Xin-Qiang] Rhein Westfal TH Aachen, D-52056 Aachen, Germany.
通讯机构：
[Yang, Ya-Dong] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.
关键词：
rare decays;beyond standard model;B-physics;CP violation
摘要：
Combining the up-to-date experimental information on B -> pi K, pi K* and rho K decays, we revisit the decay rates and CP asymmetries of these decays within the framework of QCD factorization. Using an infrared finite gluon propagator of Cornwall prescription, we find that the time-like annihilation amplitude could contribute a large strong phase, while the space-like hard spectator scattering amplitude is real. Numerically, we find that all the branching ratios and most of the direct CP violations, except A(CP)(B-+/- -> K-+/-pi(0)), agree with the current experimental data with an effective gluon mass m(g) similar or equal to 0.5 GeV. Taking the unmatched difference in direct CP violations between B -> pi(0) K-+/- and pi K--/+(+/-) decays as a hint of new physics, we perform a model-independent analysis of new physics contributions with a set of (s) over bar (1 + gamma(5))b circle times (q) over bar (1 + gamma(5))q (q=u,d) operators. Detail analyses of the relative impacts of the operators are presented in five cases. Fitting the twelve decay modes, parameter spaces are found generally with nontrivial weak phases. Our results may indicate that both strong phase from annihilation amplitude and new weak phase from new physics are needed to resolve the pi K puzzle. To further test the new physics hypothesis, the mixing-induced CP violations in B -> pi K-0(s) and rho K-0(s) are discussed and good agreements with the recent experimental data are found.
期刊：
Journal of High Energy Physics,2007年2007(6):038- ISSN：1029-8479
通讯作者：
Chang, Qin
作者机构：
[Chang, Qin] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China.;Chinese Acad Sci, Inst Theoret Phys, Beijing 100080, Peoples R China.;Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China.
通讯机构：
[Chang, Qin] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.
关键词：
sum rules;1/N expansion;chiral lagrangians
摘要：
We investigate whether the anomalous tensor operators with the Lorentz structure (sigma(mu nu)(1 + gamma(5)) circle times sigma(mu nu) (1 + gamma(5)), which could provide a simple resolution to the polarization anomaly observed in B -> phi K* decays, could also provide a coherent resolution to the large B(B -> eta K*) and survive bounds from B -> eta K decays. Parameter spaces satisfying all these experimental data are obtained, and found to be dominated by the color-octet tensor operator contribution. Constraints for the equivalent solution with (1 + gamma(5)) circle times (1 + gamma(5)) operators are also derived and found to be dominated by the color-singlet one. With the constrained parameter spaces, we finally give predictions for B-s ->phi phi decay, which could be tested at the Fermilab Tevatron and the LHC-b experiments.
作者机构：
[Ablikim, M.] Inst High Energy Phys, Beijing 100039, Peoples R China.;CCAST, Beijing 100080, Peoples R China.;Guangxi Normal Univ, Guilin 541004, Peoples R China.;Henan Normal Univ, Xinxiang 453002, Peoples R China.;Huazhong Normal Univ, Dept Phys, Wuhan 430070, Peoples R China.
通讯机构：
[Ablikim, M.] I;Inst High Energy Phys, Beijing 100039, Peoples R China.
作者机构：
[Ablikim, M] Inst High Energy Phys, Beijing 100039, Peoples R China.;China Ctr Adv Sci & Technol, Beijing 100080, Peoples R China.;Guangxi Normal Univ, Guilin 541004, Peoples R China.;Henan Normal Univ, Xinxiang 453002, Peoples R China.;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Ablikim, M] I;Inst High Energy Phys, Beijing 100039, Peoples R China.
摘要：
The cross sections for D-0(D) over bar (0) and D+D- production at 3.773 GeV have been measured with BES-II detector at BEPC. These measurements are made by analyzing a data sample of about 17.3 pb(-1) collected at the center-of-mass energy of 3.773 GeV. Observed cross sections for the charm pair production are radiatively corrected to obtain the tree level cross section for DD production. A measurement of the total tree level hadronic cross section is obtained from the tree level DD cross section and an extrapolation of the R-uds below the open charm threshold. (C) 2004 Elsevier B.V. All rights reserved.
期刊：
HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION,2004年28(1):1-10 ISSN：0254-3052
通讯作者：
Bai, JZ
作者机构：
[Bai, JZ] CAS, Inst High Energy Phys, Beijing 100039, Peoples R China.;Univ Sci & Technol China, Dept Modern Phys, Hefei 230027, Peoples R China.;Shandong Univ, Dept Phys, Jinan 250100, Peoples R China.;Zhejiang Univ, Dept Phys, Hangzhou 310028, Peoples R China.;Shanghai Jiao Tong Univ, Dept Appl Phys, Shanghai 200030, Peoples R China.
通讯机构：
[Bai, JZ] C;CAS, Inst High Energy Phys, Beijing 100039, Peoples R China.
关键词：
BES;BEPC;D-0 meson;branching fraction
摘要：
We report the results of an experimental study of the exclusive hadronic decays for D-0 --> K(s)(0)pi(+) pi(-) and (KsK+K-)-K-0 and their resonant structures using BES-I detector at the BEPC Collider. Using the data sample of 22.3 pb(-1) collected at the center-of-mass energy roots = 4.03 GeV, we measured the branching fraction for D-0 --> (K) over bar (0) pi(+) pi(-) to be (5.32 +/- 0.53 +/- 0.40)%, the branching fractions for the decays D-0 --> K* - pi(+), D-0 --> and D-0 --> (K) over bar (0) (pi(+) pi(-))(non-resonant) to be (6.05 +/- 0.32 +/- 0.49)%, (1.17 +/- 0.17 +/- 0.13)% and (1.35 +/- 0.22 +/- 0.17)% respectively. We measured the branching fractions Br(D-0 --> f) to be (1.04 +/- 0.24 +/- 0.16)% for f = (K) over bar (0) K+ K-, (1.12 +/- 0.34 +/- 0.15)% for f = (K) over bar (0)phi and (0.27 +/- 0.13 +/- 0.03)% for f = (K) over bar (0) (K+ K-)(non-phi).
期刊：
HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION,2002年26(2):93-99 ISSN：0254-3052
通讯作者：
Bai, JZ
作者机构：
[Bai, JZ] CAS, Inst High Energy Phys, Beijing 100039, Peoples R China.;Liaoning Univ, Dept Phys, Shenyang 110036, Peoples R China.;Hunan Univ, Dept Appl Phys, Changsha 410082, Peoples R China.;Wuhan Univ, Coll Phys & Elect Informat, Wuhan 430072, Peoples R China.;Henan Normal Univ, Coll Phys & Informat Engn, Xinxiang 453002, Peoples R China.
通讯机构：
[Bai, JZ] C;CAS, Inst High Energy Phys, Beijing 100039, Peoples R China.
关键词：
Beijing spectrometer;J/psi particle;Sigma(0) particle;angular distribution;branching ratio
摘要：
With 7.8 million produced J/psi events collected by the BES detector at the BEPC, the decay J/psi-->Sigma(0)Sigma(0) is analysed. The branching ratio is measured to be BR(J/psi-->Sigma(0)Sigma(0)) = (0.97 +/- 0.04 +/- 0.24) x 10(-3). The angular distribution is of the form dN/dcostheta = N-0(1 + alphacos(2)theta) with alpha value of -0.21 +/- 0.27 +/- 0.13.
摘要：
We report a measurement of the absolutely inclusive semileptonic branching fractions of D- and (D-0) over bar mesons, using a data sample of 22.3 pb(-1) collected with BES detector at BEPC e(+) e Collider at roots = 4.03 GeV and based on the method of "combinative D+ and D-0 single and double tags". The measured values of the branching fractions for D- --> e(-) X and (D-0) over bar --> e(-) X are ( 21.8 +/- 8.5 +/- 4.2)% and (8.9 +/- 3.0 +/- 1.6)%, respectively. The measured ratio of the branching fractions is BF(D- --> e(-) X)/BF (D0 --> e (-) X) -2.4 +/- 1.7 +/- 0.8.
期刊：
HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION,2001年25(6):465-475 ISSN：0254-3052
通讯作者：
Rong, G
作者机构：
[Rong, G] Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China.;Univ Sci & Technol China, Dept Modern Phys, Anhua 230026, Peoples R China.;Shandong Univ, Dept Phys, Jinan 250100, Peoples R China.;Hangzhou Univ, Dept Phys, Hangzhou 310028, Peoples R China.;Shanghai Jiao Tong Univ, Dept Appl Phys, Shanghai 200030, Peoples R China.
通讯机构：
[Rong, G] C;Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China.
关键词：
Beijing Electron Positron Collider (BEPC);Beijing Spectrometer (BES);D-s(+) Meson;D-s(+) single tag;branching fraction;production cross section;radiative correction
摘要：
Measurement of the production cross section of the D-s(+) D-s(-) in e(+) e(-) annihilation at the Center-of-Mass Energy of roots = 4.03 GeV is reported in the paper. The cross section for the D: DI production has been measured using a data sample of 22.3 pb(-1) collected with BES detector at BEPC e(+) e(-) collider. The D-s(+) measons are reconstructed in the phi pi (+), (K*(0)) over barK(+) and (K-0) over barK(+) decay modes. A total number of 94 +/- 13 singly tagged D-s(+) events is obtained from the three modes. This yelds the cross section value sigmaD(s)(prod+)D(s)(-) = (451 +/- 63 +/- 118)pb for D-s(+) D-s(-) production. Based on the numbers of singly tagged D-s(+) events for each of the three decay modes,the decay branching fractions for D-s(+) --> (K*(0)) over barK(+) and (K-0) over barK(+) have been determined to be (3.02 +/- 0.94 +/- 0.91)% and (3.28 +/- 1.22 +/- 0.94)%, respectively.
