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تسجيل مستخدم جديدTriple Higgs coupling effect on $h^0 to b bar b$ and $h^0 to tau^+ tau^-$ in the 2HDM
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We study the one loop electroweak radiative corrections to $h^0to bbar{b}$ and $h^0to tau^+tau^-$ in the framework of two Higgs doublet Model (2HDM). We evaluate the deviation of these couplings from their Standard Model (SM) values. $h^0to bbar{b}$ and $h^0to tau^+tau^-$ may receives large contribution from triple couplings $h^0H^0H^0$, $H^0h^0h^0$, $h^0A^0A^0$ and $h^0H^+H^-$ which are absent in the Standard Model. It is found that in 2HDM, these corrections could be significant and may reach more than 20% for not tow heavy $H^0$ or $A^0$ or $H^pm$. We also study the ratio of branching ratios $R=BR(h^0to bbar{b})/BR(h^0to tau^+tau^-)$ of Higgs boson decays which could be used to disentangle SM from other models such as 2HDM.
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It is still an open question whether the new scalar particle discovered at the LHC with a mass of 125 GeV is the SM Higgs boson or it belongs to models of new physics with an extended Higgs sector, as the MSSM or 2HDM. The ratio of branching fraction
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ading QCD corrections and estimate uncertainties in the theoretical calculation. Our analysis will contribute to probe an extended Higgs sector at B factory experiments.
We compute the width of the decay $h^0$ (125 GeV) $to b bar{b}$ at next-to-leading order in the general MSSM with quark-flavour violation (QFV). We study the effect of mixing between the second and the third generation of squarks, taking into account
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We evaluate long-distance electromagnetic (QED) contributions to $bar{B}{}^0 to D^+ tau^{-} bar{ u}_{tau}$ and $B^- to D^0 tau^{-} bar{ u}_{tau}$ relative to $bar{B}{}^0 to D^+ mu^{-} bar{ u}_{mu}$ and $B^- to D^0 mu^{-} bar{ u}_{mu}$, respectively,
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