Lepton flavor violating Z->l_1^+ l_2^- decay in the split fermion scenario in the two Higgs Doublet model

We predict the branching ratios of Z-> e^{\pm} \mu^{\pm}, Z-> e^{\pm} \tau^{\pm} and Z-> \mu^{\pm} \tau^{\pm} decays in the framework of the 2HDM, in the split fermion scenario. We observe that the branching ratios are not sensitive to a single extra dimension, however, this sensitivity is considerably large for two extra dimensions.Comment: 20 pages, 7 figures, 1 table

The Lorentz and CPT violating effects on the charged Higgs boson decays H^+ -> W^+ H^0 (h^0,A^0)

We study the decay widths of the processes H^+\to W^+ H^0 (h^0,A^0), including the Lorentz violating effects and analyze the possible CPT violating asymmetry arising from CPT odd coefficients. We observe that these effects are too small to be detected, since the corresponding coefficients are highly suppressed at the low energy scale.Comment: 15 pages, 6 figure

The effects of non-universal extra dimensions on the \tau\to \mu \bar{\nu_i} \nu_i decay

We study \tau\to \mu \bar{\nu_i} \nu_i, i=e,\mu,\tau decays in the two Higgs doublet model, with the inclusion of one and two spatial non-universal extra dimensions. We observe that the branching ratio is sensitive to two extra dimensions in contrary to a single extra dimension.Comment: 16 pages, 5 figure

Dark matter as a localized scalar in the extra dimension

We consider a standard model singlet which is accessible to a single extra dimension and its zero mode is localized with Gaussian profile around a point different than the origin. This zero mode scalar is a possible candidate for the dark matter and its annihilation rate is sensitive to the compactification radius of the extra dimension, the localization width and the position. For the case of non resonant annihilation, we estimated the dark matter scalar location around a point, at a distance \sim 3 \times localization width from the origin, by using the annihilation rate which is based on the current relic density.Comment: 9 pages, 3 figure

Annihilation cross sections and interaction couplings of the dark matter candidates in the warped and flat extra dimensions

We consider a scenario with an additional scalar standard model singlet $\phi_S$, living in a single extra dimension of the RS1 background. The zero mode of this scalar which is localized in the extra dimension is a dark matter candidate and the annihilation cross section is strongly sensitive to its localization parameter. As a second scenario, we assume that the standard model Higgs field is accessible to the fifth flat extra dimension. At first we take the additional standard model singlet scalar field as accessible to the sixth extra dimension and its zero mode is a possible dark matter candidate. Second, we consider that the new standard model singlet, the dark matter candidate, lives in four dimensions. In both choices the KK modes of the standard model Higgs field play an observable role for the large values of the compactification radius $R$ and the effective coupling \lambda_{S} is of the order of 10^{-2}-10^{-1} (10^{-6}) far from (near to) the resonant annihilation.Comment: 14 pages, 5 figure

Higgs to diphoton decay rate and the antisymmetric tensor unparticle mediation

We study the contribution of the antisymmetric tensor unparticle mediation to the diphoton production rate of the Higgs boson and try to explain the discrepancy between the measured value of the decay width of the discovered new resonance and that of the standard model Higgs boson. We observe that tree level contribution of the antisymmetric unparticle mediation is a possible candidate to explain the measured value of the diphoton decay rate.Comment: 12 pages, 4 figure

The annihilation cross section of dark matter which is driven by scalar unparticle

We analyze the annihilation cross section of dark matter which interacts with the standard model sector over the scalar unparticle propagator. We observe that the annihilation cross section of dark matter pair is sensitive to the dark matter mass and the scaling dimension of scalar unparticle. We estimate a range for the dark matter mass and the scaling dimension of scalar unparticle by using the current dark matter abundance.Comment: 9 pages, 4 figure