부산대학교 도서관

We extend the work [1] to a more general and detailed analysis through studying the naturalness problem and B physics constraints within the context of two higgs doublets model augmented with a complex scalar triplet field (2 H D M c T). We first derive the modified Vetman conditions and show that naturalness problem might be evaded at the electroweak scale. Then, we evaluate the branching ratio of B ¯ → X s γ radiative decay at the Next to leading order. Besides unitarity, boundedness from below constraints and the present collider data from Higgs signal rate measurements, the parameter space of 2 H D M c T is then revisited to see how the modified Veltman conditions and B ¯ → X s γ experimental bounds induce significant delimitations. Our analysis shows that the naturalness affects drastically the masses of heavy Higgs h 3 , A 2 , H 2 ± and H ± ±. More specifically, we considered three benchmark scenarios corresponding to μ 2 > 20 , 40 , 70 GeV. For μ 2 > 40 , we find stringent upper limits on m h 2 , m A 1 and m H 1 ± at 880, 920 and 918 GeV respectively. If, in addition, the measurements of B ¯ → X s γ decay rate are also considered, the lower masses limits of nonstandard Higgs bosons (h 2 , h 3 , A 1 , A 2 , H 1 ± , H 2 ± , H ± ±) are pushed up to higher values located between 490 and 750 GeV. Besides, we also demonstrate that the B ¯ → X s γ experimental limits can only be accommodated within 2 H D M c T if two conditions are fullfilled: α 1 parameter positive and the Higgs mass hierarchy m h 3 > m H 2 ± > m H ± ± . [ABSTRACT FROM AUTHOR]