arXiv subjects

P. Paradisi

Publications and source records attributed to P. Paradisi.

21 records · Page 2Linked to original sources

arXiv2006

Higgs-Mediated e -> mu transitions in II Higgs doublet Model and Supersymmetry

We study the phenomenology of the e-mu lepton flavour violation (LFV) in a general two Higgs Doublet Model (2HDM) including the supersymmetric case. We compute the decay rate expressions of mu -> e gamma, mu -> eee, and mu -> e conversion in nuclei at two loop level. In particular, it is shown that mu -> e gamma is generally the most sensitive channel to probe Higgs-mediated LFV. The correlations among the decay rates of the above processes are also discussed.

hep-ph↗

arXiv2006

Probing New Physics through mu-e Universality in K->lnu

The recent NA48/2 improvement on R_K=Gamma(K->e nu_e)/Gamma(K->mu nu_mu) emphasizes the role of K_l2 decays in probing the mu-e universality. Supersymmetric (SUSY) extensions of the Standard Model can exhibit mu-e non-universal contributions. Their origin is twofold: those deriving from lepton flavor conserving couplings are subdominant with respect to those arising from lepton flavor violating (LFV) sources. We show that mu-e non-universality in K_l2 is quite effective in constraining relevant regions of SUSY models with LFV (for instance, supergravities with a see-saw mechanism for neutrino masses). A comparison with analogous bounds coming from tau LFV decays proves the relevance of the measurement of R_K to probe LFV in SUSY.

hep-ph↗

arXiv2006

Higgs--mediated K -> pi nu nu-bar in the MSSM at large tan(beta)

We analyze the impact of Higgs-mediated amplitudes on the rare decays KL -> pi0 nu nu-bar and K+ -> pi+ nu nu-bar in the MSSM with large tan(beta) and general flavour mixing. We point out that, going beyond the minimal flavour violation hypothesis, Z-penguin amplitudes generated by charged-Higgs exchange can induce sizable modifications of K -> pi nu nu-bar rates. Interestingly, these effects scale as tan^4(beta) at the amplitude level. For large values of tan(beta), this mechanism allows deviations from the SM expectations even for tiny (CKM-type) off-diagonal mixing terms in the right-handed squark sector.

hep-ph↗