共查询到20条相似文献,搜索用时 15 毫秒
1.
In the framework of R-parity violating supersymmetry, we investigate the time dependent CP asymmetry SφKs anomaly of B→φKs decay. When the values of the weak phase φ in the R-parity violating coupling fall into certain parameter spaces (246°〈 φ 〈 263°) we find that this anomaly can be easily explained; at the same time, the branching ratio of B→φKs decay can also be in agreement with experimental measurements. 相似文献
2.
In past years,several hints of lepton flavor universality(LFU)violation have emerged from the b→ct■,and b→sl~+l-data.More recently,the Belle Collaboration has reported the first measurement of the D* longitudinal polarization fraction in the B→D*τV decay.Motivated by this intriguing result,along with the recent measurements of RJ/Ψand τ polarization,we present the study of b→ct■ decays in supersymmetry(SUSY)with R-parity violation(RPV).We consider B→D(*)t■,Bc→ηct■,Bc→J/ψt■ and ∧b→∧ct■ modes and focus on the branching ratios,LFU ratios,forward-backward asymmetries,polarizations of daughter hadrons,and the τ lepton.The RPV SUSY was capable of explaining the RD(*) anomalies at the 2σ level,after taking into account various flavor constraints.In the allowed parameter space,the differential branching fractions and LFU ratios are largely enhanced by the SUSY effects,especially in the large dilepton invariant mass region.Moreover,a lower bound B(B~+→K~+vv)7.37×10~(-6) is obtained.These observables could provide testable signatures at the high-luminosity LHC and SuperKEKB,and correlate with direct searches for SUSY. 相似文献
3.
Ashutosh Kumar Alok Sudhir Kumar Gupta 《The European Physical Journal C - Particles and Fields》2010,65(3-4):491-500
We study B s →μ + μ ? in the context of the R-parity violating minimal supergravity in the high-tan?β regime. We find that the lowest value of the branching ratio can go well below the present LHCb sensitivity and hence B s →μ + μ ? can even be invisible to the LHC. We also find that the present upper bound on Br?(B s →μ + μ ?) puts strong constraint on the minimal supergravity parameter space. The constraints become more severe if the upper bound is close to its standard model prediction. 相似文献
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5.
Using the QCD factorization approach, we investigate the large branching ratios of B→ηK^* decays and the SCKs anomaly of B→φKs decay in the two Higgs doublet model Ⅲ. With the contributions of flavour-changing neutral current mediated by the neutral Higgs bosons H^0, h^0 and A^0 at the tree level, we provide a coherent resolution to these anomalies within the constrained parameter spaces, which are 120 〈|λbs λss| 〈136. This will be really interesting in searching for the signs of new physics. 相似文献
6.
In an R-parity nonconserving supersymmetric theory, the lighter stop can dominantly decay into b&mgr; and btau if R-parity breaking has to explain the neutrino mass and mixing pattern suggested by the data on atmospheric muon neutrinos. This should give rise to dilepton + dijet and single - lepton + jets, signals identical with those of the top quark at the Fermilab Tevatron. One can thus constrain the stop parameter space using the current top search data and can similarly look for the first signals of supersymmetry at the upgraded runs of the Tevatron. 相似文献
7.
We calculate direct CP-violating rate asymmetries in chargedB→PP andB→VP decays arising from the interference of amplitudes with different strong and CKM phases. The perturbative strong phases develop at order α s from absorptive parts of one-loop matrix elements of the next-to-leading logarithm corrected effective Hamiltonian. CPT constraints are maintained. Based on this model, we find that partial rate asymmetries between charge conjugateB ± decays can be as high as 20% for certain channels with branching ratios in the 10?6 range. Because the $c\bar c$ threshold lies so close to the physical momentum scale, the asymmetries depend sensitively on the model assumptions used to evaluate the imaginary parts of the matrix elements, in particular, on the internal momentum transfer. The charge asymmetries of partial rates would provide unambiguous evidence for direct CP violation. 相似文献
8.
Aaij R Abellan Beteta C Adeva B Adinolfi M Adrover C Affolder A Ajaltouni Z Albrecht J Alessio F Alexander M Alkhazov G Alvarez Cartelle P Alves AA Amato S Amhis Y Anderson J Appleby RB Aquines Gutierrez O Archilli F Arrabito L Artamonov A Artuso M Aslanides E Auriemma G Bachmann S Back JJ Bailey DS Balagura V Baldini W Barlow RJ Barschel C Barsuk S Barter W Bates A Bauer C Bauer T Bay A Bediaga I Belogurov S Belous K Belyaev I Ben-Haim E Benayoun M Bencivenni G Benson S Benton J Bernet R 《Physical review letters》2012,108(11):111602
A search for time-integrated CP violation in D(0)→h(-)h(+) (h=K, π) decays is presented using 0.62 fb(-1) of data collected by LHCb in 2011. The flavor of the charm meson is determined by the charge of the slow pion in the D(*+)→D(0)π(+) and D(*-)→D[over ˉ](0)π(-) decay chains. The difference in CP asymmetry between D(0)→K(-)K(+) and D(0)→π(-)π(+), ΔA(CP)≡A(CP)(K(-)K(+))-A(CP)(π(-)π(+)), is measured to be [-0.82±0.21(stat)±0.11(syst)]%. This differs from the hypothesis of CP conservation by 3.5 standard deviations. 相似文献
9.
《Physics Reports》2002,370(6):537-680
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11.
M. Tanimoto K. Hirayama T. Shinmoto K. Senba 《Zeitschrift fur Physik C Particles and Fields》1990,48(1):99-104
The CP violating asymmetry in theB→K? decay is studied in both supersymmetric model and three Higgs doublets model. The absorptive part of the penguin amplitude leads to the CP violating asymmetry in theB u +- →K ±? decays, which is at most 3% due to the GIM mechanism in the standard model. However, the asymmetry could be relatively large if there exists a new source of the imaginary component in the decay amplitude. In the supersymmetric model, the contributions of the imaginary part of the super-penguin and the super-box processes rather suppress the magnitude of the asymmetry, whereas in the three Higgs doublets model, that of the charged Higgs-penguin process could significantly enhance it. 相似文献
12.
Hoi CT Chang P Aihara H Asner DM Aushev T Bakich AM Belous K Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Browder TE Chang MC Chao Y Chen A Chen KF Chen P Cheon BG Chilikin K Cho K Choi Y Danilov M Drásal Z Drutskoy A Eidelman S Fast JE Gaur V Gabyshev N Goh YM Golob B Haba J Hayasaka K Hoshi Y Hou WS Hsiung YB Hyun HJ Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Kang JH Kawasaki T Kim HJ Kim HO Kim JB Kim JH Kim KT Kim MJ Kinoshita K Ko BR Kobayashi N Kodyš P Korpar S 《Physical review letters》2012,108(3):031801
We report measurements of the branching fractions and CP asymmetries for B(±)→ηh(±) (h=K or π) and the observation of the decay B(0)→ηK(0) from the final data sample of 772×10(6) B ?B pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B(±)→ηK(±))=(2.12±0.23±0.11)×10(-6), B(B(±)→ηπ(±))=(4.07±0.26±0.21)×10(-6), and B(B(0)→ηK(0))=(1.27(-0.29)(+0.33)±0.08)×10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (σ). We also find evidence for CP violation in the charged B modes, A(CP)(B(±)→ηK(±))=-0.38±0.11±0.01 and A(CP)(B(±)→ηπ(±))=-0.19±0.06±0.01 with significances of 3.8 σ and 3.0 σ, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively. 相似文献
13.
Azeem Mir Farida Tahir Kamaluddin Ahmed 《The European Physical Journal C - Particles and Fields》2010,65(3-4):475-490
We study the decay rate of the process B→Kl + l ? (l=e,μ) and some of its other related observables, like the forward–backward asymmetry (A FB), polarization asymmetry (PA), double branching ratio and CP asymmetry (A CP) in the R-parity violating Minimal Supersymmetric Standard Model ( $\not \!{R}_{p}$ MSSM). We have performed an error analysis of the differential branching fraction, A FB and CP asymmetry. The analysis shows that theoretical results based on $\not \!{R}_{p}$ MSSM as an additional effect are compatible with the standard model. A FB is found to be zero, in agreement with SM. The average A CP is not only found to be significant in comparison with SM, but it is also compatible with the measured value within errors. 相似文献
14.
Aaltonen T Álvarez González B Amerio S Amidei D Anastassov A Annovi A Antos J Apollinari G Appel JA Apresyan A Arisawa T Artikov A Asaadi J Ashmanskas W Auerbach B Aurisano A Azfar F Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Barria P Bartos P Bauce M Bauer G Bedeschi F Beecher D Behari S Bellettini G Bellinger J Benjamin D Beretvas A Bhatti A Binkley M Bisello D Bizjak I Bland KR Blumenfeld B Bocci A Bodek A Bortoletto D Boudreau J Boveia A Brigliadori L Brisuda A Bromberg C Brucken E 《Physical review letters》2011,107(26):261802
We present the first measurement of polarization and CP-violating asymmetries in a B(s)(0) decay into two light vector mesons, B(s)(0)→φφ, and an improved determination of its branching ratio using 295 decays reconstructed in a data sample corresponding to 2.9 fb(-1) of integrated luminosity collected by the CDF experiment at the Fermilab Tevatron collider. The fraction of longitudinal polarization is determined to be f(L)=0.348±0.041(stat)±0.021(syst), and the branching ratio B(B(s)(0)→φφ)=[2.32±0.18(stat)±0.82(syst)]×10(-5). Asymmetries of decay angle distributions sensitive to CP violation are measured to be A(u)=-0.007±0.064(stat)±0.018(syst) and A(v)=-0.120±0.064(stat)±0.016(syst). 相似文献
15.
W. Bernreuther G. W. Botz D. Bruß P. Haberl O. Nachtmann 《Zeitschrift fur Physik C Particles and Fields》1995,68(1):73-80
We discuss the effect of CP-violatingZb $\bar b$ Zb $\bar b$ G andZb $\bar b$ γ couplings on the width Γ(Z→b $\bar b$ X). The presence of such couplings leads in a natural way to an increase of this width relative to the prediction of the standard model. Various strategies of a direct search for such CP-violating couplings by using CP-odd observables are outlined. The number ofZ bosons required to obtain significant information on the couplings in this way is well within the reach of present LEP experiments. 相似文献
16.
《Physics letters. [Part B]》1987,199(1):139-146
The decay rates of KL → 2γ and KS → 2γ have been measured at the CERN SPS. The results are Γ(KL→2γ)/χ(KL→2π0)=0.632±0.004±0.008 and Γ(KS→2γ)/Γ(KL→2γ)=2.3 ±1.0±0.4. This is the first observation of KS→2γ decays. 相似文献
17.
We study the rare B decay B→K*ℓ+ℓ- using soft-collinear effective theory (SCET). At leading power in 1/mb, a factorization formula is obtained valid to all orders in αs. For phenomenological application, we calculate the decay amplitude including order αs corrections, and resum the logarithms by evolving the matching coefficients from the hard scale
down to the scale
. The branching ratio for B→K*ℓ+ℓ- is uncertain due to the imprecise knowledge of the soft form factors ζ⊥(q2) and ζ∥(q2). Constraining the soft form factor ζ⊥(q2=0) from data on B→K*γ yields ζ⊥(q2=0)=0.32±0.02. Using this input, together with the light-cone sum rules to determine the q2-dependence of ζ⊥(q2) and the other soft form factor ζ∥(q2), we estimate the partially integrated branching ratio in the range 1 GeV2≤q2≤7 GeV2 to be (2.92+0.67
-0.61)×10-7. We discuss how to reduce the form factor related uncertainty by combining data on B→ρ(→ππ)ℓνℓ and B→K*(→Kπ)ℓ+ℓ-. The forward-backward asymmetry is less sensitive to the input parameters. In particular, for the zero-point of the forward-backward
asymmetry in the standard model, we get q0
2=(4.07+0.16
-0.13)
GeV2. The scale dependence of q0
2 is discussed in detail.
PACS 13.25.Hw, 12.39.St, 12.38.Bx 相似文献
18.
We calculate the branching ratio of B→J/ψπ0 with a mixed formalism that combines the QCD-improved factorization and the perturbative QCD approaches. The result is consistent with experimental data.The quite small penguin contribution in B→J/ψπ0 decay can be calculated with this method. We suggest two methods to extract the weak phase β. One is through the dependence of the mixing induced CP asymmetry SJ/ψπ0 on the weak phase β, the other is from the relation of the total asymmetry ACP with the weak phase β. Our results show that the deviation △SJ/ψπ0 of the mixing induced CP asymmetry from sin(-2β) is of O(10-3) and has much less uncertainty. The above O(10-3) deviation can provide a good reference for identifying new physics. 相似文献
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20.
Adachi I Aihara H Asner DM Aulchenko V Aushev T Aziz T Bakich AM Bay A Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Browder TE Chen P Cheon BG Chilikin K Chistov R Cho K Choi SK Choi Y Dalseno J Danilov M Doležal Z Drásal Z Eidelman S Epifanov D Fast JE Gaur V Gabyshev N Garmash A Goh YM Golob B Haba J Hara K Hara T Hayasaka K Hayashii H Higuchi T Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kapusta P Katayama N 《Physical review letters》2012,108(17):171802
We present a precise measurement of the CP violation parameter sin2φ1 and the direct CP violation parameter A(f) using the final data sample of 772×10(6) BB[over ˉ] pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is reconstructed in a J/ψK(S)(0), ψ(2S)K(S)(0), χ(c1)K(S)(0), or J/ψK(L)(0) CP eigenstate and its flavor is identified from the decay products of the accompanying B meson. From the distribution of proper-time intervals between the two B decays, we obtain the following CP violation parameters: sin2φ1=0.667±0.023(stat)±0.012(syst) and A(f)=0.006±0.016(stat)±0.012(syst). 相似文献