ترغب بنشر مسار تعليمي؟ اضغط هنا

Pion-Kaon interaction effects on CP violation in B -> K pi+ pi- decays

74   0   0.0 ( 0 )
 نشر من قبل Loiseau Benoit
 تاريخ النشر 2008
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We apply QCD factorization to the quasi two-body B ->(K pi) pi decays where the (K pi)-pair effective mass is limited to 1.8 GeV. Our strong interaction phases constrained by theory and pi-K experimental data yield useful information for studies of CP violation

قيم البحث

اقرأ أيضاً

150 - Svjetlana Fajfer 2004
We investigate a possibility of observing CP asymmetries in the partial widths for the decays B^- -> pi^+ pi^- K^- and B^- -> K^+ K^- K^- produced by the interference of the non-resonant decay amplitude with the resonant amplitudes. The resonant stat es which subsequently decay into pi^+ pi^- and K^+ K^- or K^- pi^+ are charmonium c(bar) c states with J^P = 0^+, 1^-, 1^+ or the phi(1020) meson. We find that the largest partial width asymmetry comes from the chi_c0 resonance, while the resonances K^*_0(1430) and psi(2S) give a partial width asymmetry of the order 10%.
The three-body charmless hadronic decay $B^0_s rightarrow K^{0}_{rm S} pi^{+}pi^{-}$ provides a number of novel possibilities to search for CP violation effects and test the Standard Model of particle physics. These include fits to the Dalitz-plot di stributions of the decay-time-integrated final state, decay-time-dependent (but without initial state flavour tagging) fits to the Dalitz-plot distribution, as well as full decay-time-dependent and flavour tagged fits. The relative sensitivities of these different approaches are investigated.
In this work, we study the localized $CP$ violation in $B^-rightarrow K^-pi^+pi^-$ and $B^-rightarrow K^- sigma(600)$ decays by employing the quasi two-body QCD factorization approach. Both the resonance and the nonresonance contributions are studied for the $B^-rightarrow K^-pi^+pi^-$ decay. The resonance contributions include those not only from $[pipi]$ channels including $sigma(600)$, $rho^0(770)$ and $omega(782)$ but also from $[Kpi]$ channels including $K^*(892)$, $K_0^*(1430)$, $K^*(1410)$, $K^*(1680)$ and $K_2^*(1430)$. By fitting the experimental data $mathcal{A_{CP}}(K^-pi^+pi^-)=0.678pm0.078pm0.0323pm0.007$ for $m_{K^-pi^+}^2<15$ $mathrm{GeV}^2$ and $0.08<m_{pi^+pi^-}^2<0.66$ $mathrm{GeV}^2$, we get the end-point divergence parameters in our model, $phi_S in [4.75, 5.95]$ and $rho_Sin[4.2, 8]$. Using these results for $rho_S$ and $phi_S$, we predict that the $CP$ asymmetry parameter $mathcal{A_{CP}} in [-0.094, -0.034]$ and the branching fraction $mathcal{B} in [1.82, 20.0]times10^{-5}$ for the $B^-rightarrow K^-sigma(600)$ decay. In addition, we also analyse contributions to the localized $CP$ asymmetry $mathcal{A_{CP}}(B^-rightarrow K^-pi^+pi^-)$ from $[pipi]$, $[Kpi]$ channel resonances and nonresonance individually, which are found to be $mathcal{A_{CP}}(B^-rightarrow K^-[pi^+pi^-] rightarrow K^-pi^+pi^-)=0.585pm0.045$, $mathcal{A_{CP}}(B^-rightarrow [K^-pi^+] pi rightarrow K^-pi^+pi^-)=0.086pm0.021$ and $mathcal{A_{CP}}^{NR}(B^-rightarrow K^-pi^+pi^-)=0.061pm0.0042$, respectively. Comparing these results, we can see that the localized $CP$ asymmetry in the $B^-rightarrow K^-pi^+pi^-$ decay is mainly induced by the $[pipi]$ channel resonances while contributions from the $[Kpi]$ channel resonances and nonresonance are both very small.
Observations are reported of different sources of $CP$ violation from an amplitude analysis of $B^+ to pi^+ pi^+ pi^-$ decays, based on a data sample corresponding to an integrated luminosity of $3 ; {rm fb}^{-1}$ of $pp$ collisions recorded with the LHCb detector. A large $CP$ asymmetry is observed in the decay amplitude involving the tensor $f_2(1270)$ resonance, and in addition significant $CP$ violation is found in the $pi^+ pi^-$ S-wave at low invariant mass. The presence of $CP$ violation related to interference between the $pi^+ pi^-$ S-wave and the P-wave $B^+ to rho(770)^0 pi^+$ amplitude is also established; this causes large local asymmetries but cancels when integrated over the phase space of the decay. The results provide both qualitative and quantitative new insights into $CP$-violation effects in hadronic $B$ decays.
101 - KTeV Collaboration 1999
We report the first observation of a manifestly CP violating effect in the K(L)->pi+pi-e+e- decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle phi between the decay planes of the e+e- and pi+p i- pairs in the K(L) center of mass system. After acceptance corrections, the overall asymmetry is found to be 13.6+-2.5 (stat) +-1.2 (syst)%. This is the largest CP-violating effect yet observed integrating over the entire phase space of a mode and the first such effect observed in an angular variable.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا