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CP-Violation from Spin-1 Resonances in a Left-Right Dynamical Higgs Context
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作者 阮坤明 舒菁 Juan Yepes 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第7期93-103,共11页
New physics field content in the nature, more specifically, from spin-1 resonances sourced by the extension of the SM local gauge symmetry to the larger local group SU(2)_LSU(2)_R U(1)_(B-L), may induce CP-violation s... New physics field content in the nature, more specifically, from spin-1 resonances sourced by the extension of the SM local gauge symmetry to the larger local group SU(2)_LSU(2)_R U(1)_(B-L), may induce CP-violation signalling NP effects from higher energy regimes. In this work we completely list and study all the CP-violating operators up to the p^4-order in the Lagrangian expansion, for a non-linear left-right electroweak chiral context and coupled to a light dynamical Higgs. Heavy right handed fields can be integrated out from the physical spectrum, inducing thus a physical impact in the effective gauge couplings, fermionic electric dipole moment, and CP-violation in the decay h→ ZZ*→4 l that are briefly analysed. The final relevant set of effective operators have also been identified at low energies. 展开更多
关键词 cp-violation spin-1 resonances dynamical Higgs
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Distinguishable RGE Running Effects Between Dirac Neutrinos and Majorana Neutrinos with Vanishing Majorana CP-Violating Phases
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作者 XING Zhi-Zhong ZHANG He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期525-530,共6页
In a novel parametrization of neutrino mixing and in the approximation of τ-lepton dominance, we show that the one-loop renormalization-group equations (RGEs) of Dirac neutrinos are different from those of Majorana... In a novel parametrization of neutrino mixing and in the approximation of τ-lepton dominance, we show that the one-loop renormalization-group equations (RGEs) of Dirac neutrinos are different from those of Majorana neutrinos even if two Majorana CP-violating phases vanish. As the latter can keep vanishing from the electroweak scale to the typical seesaw scale, it makes sense to distinguish between the RGE running effects of neutrino mixing parameters in Dirac and Majorana cases. The differences are found to be quite large in the minimal supersymmetric standard model with sizable tan β, provided the masses of three neutrinos are nearly degenerate or have an inverted hierarchy. 展开更多
关键词 neutrino mixing Dirac neutrino Majorana neutrino Majorana cp-violating phase
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On the Preponderance of Matter over Antimatter
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作者 Golden Gadzirayi Nyambuya 《Journal of Modern Physics》 2015年第11期1441-1451,共11页
Quantum electrodynamics (QED) is built on the original Dirac equation, an equation that exhibits perfect symmetry in that it is symmetric under charge conjugation (C), space (P) and time (T) reversal and any combinati... Quantum electrodynamics (QED) is built on the original Dirac equation, an equation that exhibits perfect symmetry in that it is symmetric under charge conjugation (C), space (P) and time (T) reversal and any combination of these discrete symmetries. We demonstrate herein that while the proposed Lorentz invariant Curved Spacetime Dirac Equations (CSTD-equations) obey C, PT and CPT-symmetries, these equations readily violate P, T, CP and CT-symmetries. Realising this violation, namely the T and CT-violation, we take this opportunity to suggest that the Curved Spacetime Dirac Equations may help in solving the long standing riddle and mystery of the preponderance of matter over antimatter. We come to the tentative conclusion that if these CSTD-equations are to explain the preponderance of matter over antimatter;then, photons are to be thought of as described by the spherically curved version of this set of equations, while ordinary matter is to be explained by the parabolically and hyperbolically curved spacetime versions of this same set of equations. 展开更多
关键词 ANTIMATTER ASYMMETRIC cp-violation Curved SPACETIME DIRAC Equation
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B→ρ(ω,φ)η(′)Decays and NLO Contributions in pQCD Approach 被引量:1
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作者 ZHANG Zhi-Qing XIAO Zhen-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期885-894,共10页
By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^... By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^0(ω, φ)η('), induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for B^± → ρ^±η(') (B^0 → ρ^0(ω, φ)η(')decays, the partial NLO contributions to branching ratios are small (large) in magnitude; and (b) the pQCD predictions for ACP^dir(B^± → ρ^±η(')) are consistent with the data, while the predicted .ACP(B^0 → ρ^0(ω)η(')) are generally large in magnitude and could be tested by the forthcoming LHCb experiments. 展开更多
关键词 pQCD factorization approach B meson decays branching ratio cp-violating asymmetry
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Studies of B_s^O→η′η′ Decays in pQCD Approach
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作者 LIU Xin XIAO Zhen-Jun WANG Hui-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期981-986,共6页
We calculate the CP averaged branching ratios and CP-violating asymmetries for Bs^0 → η'η' and η'η' decays in the perturbative QCD (pQCD) approach here. The pQCD predictions for the C P-averaged branchin... We calculate the CP averaged branching ratios and CP-violating asymmetries for Bs^0 → η'η' and η'η' decays in the perturbative QCD (pQCD) approach here. The pQCD predictions for the C P-averaged branching ratios are Br(Bs^0 → ηη)=(14.2-7.5^+18.0) ×10^-6,Br(Bs^0 → ηη')=(12.4-7.0^+18.2)×10^-6,and Br(Bs^0 → η'η') =(9.2-4.9^+15.3)×10^-6, which agree well with those obtained by employing the QCD factorization approach and also be consistent with available experimental upper limits. The gluonic contributions are small in size: less than 7% for Bs →ηηand ηη' decays, and around 18% for Bs →η'η' decay. The CP-violating asymmetries for three decays are very small: less than 3% in magnitude. 展开更多
关键词 branching ratio cp-violating asymmetry perturbative QCD
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About detecting CP-violating processes in J/ψ→K~0K~0 decay
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作者 李海波 杨茂志 《Chinese Physics C》 SCIE CAS CSCD 2009年第2期85-88,共4页
Abstract Questions about detecting the CP-violating decay process of J/ψ→ K^0K^-0→ KsKs are discussed. Possible background and material regeneration effects are analyzed. The discussion can be directly extended to ... Abstract Questions about detecting the CP-violating decay process of J/ψ→ K^0K^-0→ KsKs are discussed. Possible background and material regeneration effects are analyzed. The discussion can be directly extended to other vector quarkonium decays, like γ, ψ(2S) and Ф → KsKs. 展开更多
关键词 cp-violation QUARKONIUM regeneration J/ψ decay BES
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Pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)in the PQCD approac
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作者 Yutong Chen Zewen Jiang Xin Liu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第4期82-91,共10页
We study the CP-averaged branching fractions and the CP-violating asymmetries in the pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0),where a_(0)[K^(∗)_(0)]denotes the scala... We study the CP-averaged branching fractions and the CP-violating asymmetries in the pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0),where a_(0)[K^(∗)_(0)]denotes the scalar a_(0)(980)and a_(0)(1450)[K^(∗)_(0)(800)(orκ)and K^(∗)_(0)(1430)],with the perturbative QCD factorization approach under the assumption of two-quark structure for the a_(0)and K^(∗)_(0)states.The numerical results show that the branching ratios of the B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)decays are in the order of 10^(−6),while the decay rates of the B^(s)_(0)→a^(+)_(0)a^(−)_(0)modes are in the order of 10−5.In light of the measured modes with the same quark components in the pseudoscalar sector,namely,B^(0)_(d)→K^(+)k_(-)and B^(0)_(s)→π^(+)π_(−),the predictions for the considered decay modes in this work are expected to be measured at the Large Hadron Collider beauty and/or Belle-Ⅱexperiments in the(near)future.Meanwhile,it is of great interest to find that the twist-3 distribution amplitudesφ^(S)andφ^(T)with inclusion of the Gegenbauer polynomials for the scalar a_(0)(1450)and K^(∗)_(0)(1430)states in scenario 2 contribute slightly to the branching ratios while significantly to the CP violations in the B^(0)_(d)→K^(∗)_(0)(1430)+K^(∗)_(0)(1430)−and B^(0)_(s)→a_(0)(1450)+a_(0)(1450)−decays,which indicates that,compared to the asymptoticφ^(S)andφ^(T),these Gegenbauer polynomials could change the strong phases evidently in these pure annihilation decay channels.These predictions await for the future confirmation experimentally,which could further provide useful information to help explore the inner structure of the scalars and shed light on the annihilation decay mechanism. 展开更多
关键词 B meson decays perturbative QCD factorization approach light scalar mesons branching ratios cp-violating asymmetries
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