相关论文: The Cabibbo angle : an algebraic calculation

We propose two phenomenological scenarios of lepton mass matrices and show that either of them can exactly give rise to \tan^2\theta_{13} = m_e/(m_e + 2m_\mu), \tan^2\theta_{23} = m_\mu/(m_e + m_\mu) and \tan^2\theta_{12} = (m_e m_2 +…

We point out that testing the equality of the Cabibbo angle as extracted from $\Gamma(K\rightarrow \pi l\nu)$, the ratio $\Gamma(K\rightarrow l\nu)/\Gamma(\pi\rightarrow l\nu)$ and nuclear $\beta$ decays is not identical to a test of first…

We construct a model of quark-lepton unification at the TeV scale based on an $SU(4)$ gauge symmetry, while still having acceptable neutrino masses and enough suppression in flavor changing neutral currents. An approximate $U(2)$ flavor…

We present a predictive scheme for fermion masses and mixings inspired by supersymmetric SO(10) in which the gauge hierarchy problem is resolved without fine tuning the parameters. There are six predictions in the flavor sector, all…

For a neutrino mass matrix whose texture has an approximate flavor symmetry and where one has near degenerate neutrino mass, it is shown that the tribimaximal values for atmospheric angle $\sin^{2}{\theta_{23}}=1/2$ and solar angle…

We propose a new $\mathrm{SU}(3)_C \otimes \mathrm{SU}(2)_{L}\otimes \mathrm{U}(1)_{Y}\otimes \mathrm{U}(1)_{X}$ gauge model which is non universal respect to the three fermion families of the Standard Model. We introduce additional one…

Different approaches to the quark-lepton mass problem are reviewed. The infrared quasifixed point predictions for the top quark mass are discussed for the Standard Model and its minimal supersymmetric extension, with particular reference to…

We propose a realistic A4 extension of the Standard Model involving a particular quark-lepton mass relation, namely that the ratio of the third family mass to the geometric mean of the first and second family masses are equal for down-type…

The recent measurements of the solar neutrino mixing angle theta_{sol} and the Cabibbo mixing angle theta_C reveal a surprising relation, theta_{sol}+theta_C ~ pi/4. Interpreting this empirical relation as a support of the quark-lepton…

Determining the absolute masses of neutrinos is of fundamental importance in particle physics, nuclear physics, and astrophysics. We conjecture that intrinsic mass relations exist between leptons and quarks. Using these relations and…

We study the pentaquark $uudd\bar s$ with $J=3/2$ and I=1 ($\Theta^{++}$) in the QCD sum rule approach. We derive the QCD sum rules for positive and negative parity states of the pentaquark. The QCD sum rule predicts that there exists…

A modified neutrino sector could imprint a signature on precision measurements of the quark sector because many such measurements rely on the semi-leptonic decays of the charged currents. Currently, global fits of the determinations of the…

We present a model in which the Supersymmetric Standard Model is augmented by the family symmetry $\bs{\m Z_7 \rtimes \m Z_3}$. Motivated by $SO(10)$, where the charge two-thirds and neutral Dirac Yukawa matrices are related, we propose,…

Model-independent consequences of applying a generalized hidden horizontal Z_2 symmetry to the neutrino mass matrix are explored. The Dirac CP phase delta_D can be expressed in terms of the three mixing angles as 4 c_a s_a c_s s_s s_x cos…

We relate the MNS and CKM mixing matrices using ideas from grand unification. We catalog models in terms of the family symmetries of the down quark mass matrices, and emphasize the role of the Cabibbo angle in the lepton mixing matrix. We…

In combination with supersymmetry, flavor symmetry may relate quarks with leptons, even in the absence of a grand-unification group. We propose an SU(3)xSU(2)xU(1) model where both supersymmetry and the assumed A4 flavor symmetries are…

A very precise determination of V_us can be obtained from the semi-inclusive hadronic decay width of the tau lepton into final states with strangeness. The ratio of the Cabibbo-suppressed and Cabibbo-allowed tau decay widths directly…

We formulate a predictive model of fermion masses and mixings based on a $\Delta(27)$ family symmetry. In the quark sector the model leads to the viable mixing inspired texture where the Cabibbo angle comes from the down quark sector and…

The recent results of the Planck experiment put a stringent constraint on the sum of the light neutrino masses, m1+m2+m3 < 0.23 eV (95 % CL). On the other hand, two-zero Majorana mass matrix textures predict strong correlations among the…

A comparative analysis of a number of phenomenological relationships between constants of the extended Standard Model of electromagnetic, strong and weak interactions of fundamental particles (hereinafter referred to as the extended…