644 research outputs found

    Slepton Non-Universality in the Flavor-Effective MSSM

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    Supersymmetric theories supplemented by an underlying flavor-symmetry Gf\mathcal{G}_f provide a rich playground for model building aimed at explaining the flavor structure of the Standard Model. In the case where supersymmetry breaking is mediated by gravity, the soft-breaking Lagrangian typically exhibits large tree-level flavor violating effects, even if it stems from an ultraviolet flavor-conserving origin. Building on previous work, we continue our phenomenological analysis of these models with a particular emphasis on leptonic flavor observables. We consider three representative models which aim to explain the flavor structure of the lepton sector, with symmetry groups Gf=Δ(27)\mathcal{G}_f = \Delta(27), A4,A_4, and S3S_3.Comment: References added, minor typos corrected. 28 pages, 8 figure

    Controlled flavor violation in the MSSM from a unified Δ(27)\Delta(27) flavor symmetry

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    We study the phenomenology of a unified supersymmetric theory with a flavor symmetry Δ(27)\Delta(27). The model accommodates quark and lepton masses, mixing angles and CP phases. In this model, the Dirac and Majorana mass matrices have a unified texture zero structure in the (1,1)(1,1) entry that leads to the Gatto-Sartori-Tonin relation between the Cabibbo angle and ratios of the masses in the quark sectors, and to a natural departure from zero of the θ13\theta_{13}^\ell angle in the lepton sector. We derive the flavor structures of the trilinears and soft mass matrices, and show their general non-universality. This causes large flavor violating effects. As a consequence, the parameter space for this model is constrained, allowing it to be (dis)proven by flavor violation searches in the next decade. Although the results are model specific, we compare them to previous studies to show similar flavour effects (and associated constraints) are expected in general in supersymmetric flavor models, and may be used to distinguish them.Comment: 21 pages, 6 figure

    Leptogenesis in Δ(27)\Delta(27) with a Universal Texture Zero

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    We investigate the possibility of viable leptogenesis in an appealing Δ(27)\Delta(27) model with a universal texture zero in the (1,1) entry. The model accommodates the mass spectrum, mixing and CP phases for both quarks and leptons and allows for grand unification. Flavoured Boltzmann equations for the lepton asymmetries are solved numerically, taking into account both N1N_1 and N2N_2 right-handed neutrino decays. The N1N_1-dominated scenario is successful and the most natural option for the model, with M1[109,1012]M_1 \in [10^9, 10^{12}] GeV, and M1/M2[0.002,0.1]M_1/M_2 \in [0.002, 0.1], which constrains the parameter space of the underlying model and yields lower bounds on the respective Yukawa couplings. Viable leptogenesis is also possible in the N2N_2-dominated scenario, with the asymmetry in the electron flavour protected from N1N_1 washout by the texture zero. However, this occurs in a region of parameter space which has a stronger mass hierarchy M1/M2<0.002M_1/M_2 < 0.002 , and M2M_2 relatively close to M3M_3, which is not a natural expectation of the Δ(27)\Delta(27) model.Comment: v2: 20 pages, 2 figures. Version accepted in JHE

    Neutrino masses and lepton mixing from A5×CPA_5\times{\rm CP}

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    We analyse in detail the phenomenological implications for lepton masses and mixing derived by the breaking of the discrete symmetries A5×CPA_5 \times CP into the subgroups Z2×CPZ_2 \times CP in the neutrino sector and Z5Z_5 in the charged lepton sector. We derive accurate analytic expressions for the sum of the neutrino masses Σimi\Sigma_i m_i as well as for the effective Majorana masses mβm_\beta and mββm_{\beta \beta} under different hypotheses for the flavon vevs and compare them with the exact numerical results obtained from the diagonalization of the neutrino mass matrix.Comment: 40 pages, 9 figure

    Muon and electron g2g-2 and lepton masses in flavor models

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    The stringent experimental bound on μeγ\mu \rightarrow e \gamma is compatible with a simultaneous and sizable new physics contribution to the electron and muon anomalous magnetic moments (g2)(g-2)_\ell (=e,μ\ell=e,\,\mu), only if we assume a non-trivial flavor structure of the dipole operator coefficients. We propose a mechanism in which the realization of the (g2)(g-2)_\ell correction is manifestly related to the mass generation through a flavor symmetry. A radiative flavon correction to the fermion mass gives a contribution to the anomalous magnetic moment. In this framework, we introduce a chiral enhancement from a non-trivial O(1)\mathcal{O}(1) quartic coupling of the scalar potential. We show that the muon and electron anomalies can be simultaneously explained in a vast region of the parameter space with predicted vector-like mediators of masses as large as Mχ[0.6,2.5]M_\chi\in [0.6,2.5]~TeV.Comment: 18 pages, 3 figures, 2 table

    Implications of the Muon g-2 result on the flavour structure of the lepton mass matrix

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    The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for this discrepancy but these models are much more restricted, as they would also generate off-diagonal entries in the dipole moment matrix. Therefore, if we assume that the observed discrepancy in the muon g2g-2 is explained by the contributions of a low-energy flavor symmetry, lepton flavour violating processes can constrain the structure of the lepton mass matrices and therefore the flavour symmetries themselves predicting these structures. We apply these ideas to several discrete flavour symmetries popular in the leptonic sector, such as Δ(27)\Delta (27), A4A_4, and A5CPA_5 \ltimes {\rm CP}.Comment: 21 pages; v3: comments added, typos corrected, version accepted for publication in EPJ

    Measuring Accuracy of Triples in Knowledge Graphs

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    An increasing amount of large-scale knowledge graphs have been constructed in recent years. Those graphs are often created from text-based extraction, which could be very noisy. So far, cleaning knowledge graphs are often carried out by human experts and thus very inefficient. It is necessary to explore automatic methods for identifying and eliminating erroneous information. In order to achieve this, previous approaches primarily rely on internal information i.e. the knowledge graph itself. In this paper, we introduce an automatic approach, Triples Accuracy Assessment (TAA), for validating RDF triples (source triples) in a knowledge graph by finding consensus of matched triples (among target triples) from other knowledge graphs. TAA uses knowledge graph interlinks to find identical resources and apply different matching methods between the predicates of source triples and target triples. Then based on the matched triples, TAA calculates a confidence score to indicate the correctness of a source triple. In addition, we present an evaluation of our approach using the FactBench dataset for fact validation. Our findings show promising results for distinguishing between correct and wrong triples

    LA ESTIMULACIÓN PSICOMOTRIZ EN I A INFANCIA A TRAVÉS DEL MÉTODO ESTITSOLÓGICO MULTISENSORIAL DE ATENCIÓN TEMPRANA

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    Desde una perspectiva ecológica se analiza la importancia de la estimulación psicomotriz en la infancia, empleando enfoques teóricos del desarrollo psicomotor tales como el Evolutivo o el Sistema Dinámico, resaltando dominios como el control postural, el esquema corporal, la lateralidad o el aprendizajeperceptivo-motor. Se estudian los beneficios de la Estimulación Psicomotriz Temprana y la relevancia de las prácticas parentales de estimulación mediante un estudio empírico -diseño pretest-postest - que demuestra la eficacia del Método Estitsológico Multisensorial, aplicado durante 4 meses a niños de o a 6 años que viven en contextos normalizados. Los resultados de análisis estadísticos (t de Student, ANCOVA, medidas de asociación etc.) manifiestan que existen diferencias significativas en los niveles de Motricidad Somática, Desarrollo Sensomotor, Reacción y Coordinación Motriz de los niños del grupo experimental frente a los niveles alcanzados por los niños del grupo control, cuyo ritmo de desarrollopsicomotor es menor.ABSTRACTThe importance of psychomotor stimulation in early childhood is analyzed from a contextual perspective. Theoretical approaches of psychomotor development are employed (evolutive approach, Thelen's system) highlighting areas such as postural control, body scheme, laterality and perceptive-motor learning.The benefits of Early Psychomotor Stimulation as ivell as the importance of parental practices of stimulation are studied by means of an empiric study - designed as pre-test, post-test- that demonstrates the effectiveness of the Multisensorial Estitsologic Method, applied during four months to children of 0 to 6 years old who live in standardized contexts. The results of statistical analyses (t of Student, ANCOVA, measures of association) suggest the existence of significant differences in the levels of Somatic Motility, Sensomotor Development, Reaction and Coordination, in children from the experimental group compared to the levels reached by the control group, whose rate of psychomotor development is lower
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