Study of the lepton flavor-violating Z′→τμZ'\to\tau\mu decay

The lepton flavor violating $Z^{\prime}\to\tau\mu$ decay is studied in the context of several extended models that predict the existence of the new gauge boson named $Z^\prime$. A calculation of the strength of the lepton flavor violating $Z^\prime\mu\tau$ coupling is presented by using the most general renormalizable Lagrangian that includes lepton flavor violation. We used the experimental value of the muon magnetic dipole moment to bound this coupling, from which the $\mathrm{Re}(\Omega_{L\mu\tau}\Omega^\ast_{R\mu\tau})$ parameter is constrained and it is found that $\mathrm{Re}(\Omega_{L\mu\tau}\Omega^\ast_{R\mu\tau})\sim 10^{-2}$ for a $Z^\prime$ boson mass of 2 TeV. Alongside, we employed the experimental restrictions over the $\tau\to\mu\gamma$ and $\tau\to\mu\mu^+\mu^-$ processes in the context of several models that predict the existence of the $Z^\prime$ gauge boson to bound the mentioned coupling. The most restrictive bounds come from the calculation of the three-body decay. For this case, it was found that the most restrictive result is provided by a vector-like coupling, denoted as $|\Omega_{\mu\tau}|^2$, for the $Z_\chi$ case, finding around $10^{-2}$ for a $Z^\prime$ boson mass of 2 TeV. We used this information to estimate the branching ratio for the $Z^\prime\to\tau\mu$ decay. According to the analyzed models the least optimistic result is provided by the Sequential $Z$ model, which is of the order of $10^{-2}$ for a $Z^\prime$ boson mass around 2 TeV.Comment: Revised versio

Electric dipole and magnetic quadrupole moments of the WW boson via a CP-violating HWWHWW vertex in effective Lagrangians

The possibility of nonnegligible $W$ electric dipole ($\widetilde{\mu}_W$) and magnetic quadrupole ($\widetilde{Q}_W$) moments induced by the most general $HWW$ vertex is examined via the effective Lagrangian technique. It is assumed that new heavy fermions induce an anomalous CP-odd component of the $HWW$ vertex, which can be parametrized by an $SU_L(2)\times U_Y(1)$-invariant dimension-six operator. This anomalous contribution, when combined with the standard model CP-even contribution, lead to CP-odd electromagnetic properties of the $W$ boson, which are characterized by the form factors $\Delta \widetilde{\kappa}$ and $\Delta \widetilde{Q}$. It is found that $\Delta \widetilde{\kappa}$ is divergent, whereas $\Delta \widetilde{Q}$ is finite, which reflects the fact that the latter cannot be generated at the one-loop level in any renormalizable theory. Assuming reasonable values for the unknown parameters, we found that $\widetilde{\mu}_W\sim 3-6\times 10^{-21}$ e-cm, which is eight orders of magnitude larger than the SM prediction and close to the upper bound derived from the neutron electric dipole moment. The estimated size of the somewhat less-studied $\widetilde{Q}_W$ moment is of the order of $-10^{-36}$ e-cm^2, which is fifteen orders of magnitude above the SM contribution.Comment: 7 pages, 6 figures, REVTEX styl

Non Sequential Recursive Pair Substitution: Some Rigorous Results

We present rigorous results on some open questions on NSRPS, non sequential recursive pairs substitution method (see Grassberger in \cite{G}). In particular, starting from the action of NSRPS on finite strings we define a corresponding natural action on measures and we prove that the iterated measure becomes asymptotically Markov. This certify the effectiveness of NSRPS as a tool for data compression and entropy estimation.Comment: 20 page

Consumption of the Dietary Flavonoids Quercetin, Luteolin and Kaempferol and Overall Risk of Cancer - A Review and Meta-Analysis of the Epidemiological Data

Numerous epidemiological and preclinical studies suggest that flavonoids may play an important role in the decreased risk of cancer associated with a diet rich in plant-derived foods. In this article, we have reviewed the epidemiological studies assessing the relationship between the consumption of three of the most common flavonoids, i.e. quercetin, luteolin and kaempferol, and the risk of developing cancer. We have also performed a meta-analysis on the consumption of these three flavonoids (alone and combined) and overall risk of cancer. The analysis of data from 18 case-control studies (8585 cases with cancer and 9975 control subjects) revealed that a high consumption of these three flavonoids (combined) was associated with a statistically significant reduction of overall cancer risk (OR: 0.73; 95% CI: 0.63, 0.84; p<0.01). A reduction of overall cancer risk was also observed for quercetin (OR: 0.73; 95% CI: 0.62, 0.86; p<0.01), kaempferol (OR: 0.86; 95% CI: 0.73, 1.11; p>0.05) and luteolin (OR: 0.90; 95% CI: 0.69, 1.18; p>0.05), which was statistically significant for quercetin. A high intake of these three flavonoids (combined) was also associated with a statistically significant reduction of lung cancer risk (OR: 0.67; 95% CI: 0.49, 0.91; p<0.05) and colon cancer risk (OR: 0.75; 95% CI: 0.57, 0.98; p<0.05). The analysis of data from 14 cohort studies (385033 individuals and 10809 cancer cases) showed a statistically significant reduction of overall cancer risk for the three flavonoids combined (RR: 0.89; 95% CI: 0.80, 1.00; p<0.05), for quercetin (RR: 0.82; 95% CI: 0.71, 0.96; p<0.05) and for kaempferol (RR: 0.88; 95% CI: 0.78, 0.99; p<0.05), and a non-statistically significant reduction for luteolin (RR: 0.95; 95% CI: 0.67, 1.34; p>0.05). These results suggest that consumption of foods rich in the flavonoids quercetin, kaempferol and luteolin may reduce the risk of developing cance