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Li, X. Q., Lu, J., & Pich, A. (2014). Bs,d(0) -> l(+)l(-) decays in the aligned two-Higgs-doublet model. J. High Energy Phys., 06(6), 022–39pp.
Abstract: The rare decays B-s,d(0) -> l(+)l(-) are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data.
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Botella, F. J., Branco, G. C., Carmona, A., Nebot, M., Pedro, L., & Rebelo, M. N. (2014). Physical constraints on a class of two-Higgs doublet models with FCNC at tree level. J. High Energy Phys., 07(7), 078–33pp.
Abstract: We analyse the constraints and some of the phenomenological implications of a class of two Higgs doublet models where there are flavour-changing neutral currents (FCNC) at tree level but the potentially dangerous FCNC couplings are suppressed by small entries of the CKM matrix V. This class of models have the remarkable feature that, as a result of a discrete symmetry of the Lagrangian, the FCNC couplings are entirely fixed in the quark sector by V and the ratio v(2)/v(1) of the vevs of the neutral Higgs. The discrete symmetry is extended to the leptonic sector, so that there are FCNC in the leptonic sector with their flavour structure fixed by the leptonic mixing matrix. We analyse a large number of processes, including decays mediated by charged Higgs at tree level, processes involving FCNC at tree level, as well as loop induced processes. We show that in this class of models one has new physical scalars beyond the standard Higgs boson, with masses reachable at the next round of experiments.
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Mitsou, V. A. (2013). Shedding light on dark matter at colliders. Int. J. Mod. Phys. A, 28(31), 1330052–34pp.
Abstract: Dark matter remains one of the most puzzling mysteries in Fundamental Physics of our times. Experiments at high-energy physics colliders are expected to shed light to its nature and determine its properties. This review focuses on recent searches for dark matter signatures at the Large Hadron Collider, also discussing related prospects in future e(+)e(-) colliders.
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Duarte, L., Gonzalez-Sprinberg, G. A., & Vidal, J. (2013). Top quark anomalous tensor couplings in the two-Higgs-doublet models. J. High Energy Phys., 11(11), 114–21pp.
Abstract: We compute the one loop right and left anomalous tensor couplings (g(R) and g(L), respectively) for the top quark, in the aligned two-Higgs-doublet model. They are the magnetic-like couplings in the most general parameterization of the tbW vertex. We find that the aligned two-Higgs doublet model, that includes as particular cases some of the most studied extensions of the Higgs sector, introduces new electroweak contribution's and provides theoretical predictions that are very sensitive to both new scalar masses and the neutral scalar mixing angle. For a largo area in the parameters space we obtain significant deviations in both the real and the imaginary parts of the couplings gR and gL, compared to the predictions given by the electroweak sector of the Standard Model. The most important ones are those involving the imaginary part of the left coupling g(L) and the real part of the right coupling gR. The real part of g(L), and the imaginary part of gR also show an important sensitivity to new physics scenarios. The model can also account for new CP violation effects via the introduction of complex alignment parameters that have important consequences on the values for the imaginary parts of the couplings. The top anomalous tensor couplings will be measured at the LHC and at future colliders providing a complementary insight on new physics, independent from the bounds in top decays coming from B physics and b -> s gamma.
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Barenboim, G., Bosch, C., Lopez-Ibañez, M. L., & Vives, O. (2013). Eviction of a 125 GeV “heavy”-Higgs from the MSSM. J. High Energy Phys., 11(11), 051–39pp.
Abstract: We prove that the present experimental constraints are already enough to rule out the possibility of the similar to 125 GeV Higgs found at LHC being the second lightest Higgs in a general MSSM context, even with explicit CP violation in the Higgs potential. Contrary to previous studies, we are able to eliminate this possibility analytically, using simple expressions for a relatively small number of observables. We show that the present LHC constraints on the diphoton signal strength, tau tau production through Higgs and BR(B -> X-s gamma) are enough to preclude the possibility of H-2 being the observed Higgs with m(H) similar or equal to 125 GeV within an MSSM context, without leaving room for finely tuned cancellations. As a by-product, we also comment on the difficulties of an MSSM interpretation of the excess in the gamma gamma production cross section recently found at CMS that could correspond to a second Higgs resonance at m(H) similar or equal to 136 GeV.
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