The universality of the weak interactions can be tested in semileptonic b→c transitions,and in particular in the ratios R（D＊） ≡ Γ（B → D（＊）τν）/Γ（B → D＊lν）（where 1 = μ or e）.Due to the recent diff...The universality of the weak interactions can be tested in semileptonic b→c transitions,and in particular in the ratios R（D＊） ≡ Γ（B → D（＊）τν）/Γ（B → D＊lν）（where 1 = μ or e）.Due to the recent differences between the experimental measurements of these observables by Ba Bar,Belle and LHCb on the one hand and the Standard Model predicted values on the other hand,we study the predicted ratios R（D＊）=Γ（B→D＊τ＋＂missing＂）/Γ（B→D（＊）lν）in scenarios with an additional sterile heavy neutrino of mass ～1 Ge V.Further,we evaluate the newly defined ratio R（0）≡Γ（B→τ＋＂missing＂）/Γ（B→μν） in such scenarios,in view of the future possibilities of measuring the quantity at Belle-Ⅱ.展开更多
We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of W^±→e^±e^±μ ν and μ^±^±e ν at the 14 TeV LHC. The discovery and exclusion lim...We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of W^±→e^±e^±μ ν and μ^±^±e ν at the 14 TeV LHC. The discovery and exclusion limits for sterile neutrinos are shown using both the Cut-and-Count（CC） and Multi-Variate Analysis（MVA） methods. We also discriminate between Dirac and Majorana sterile neutrinos by exploiting a set of kinematic observables which differ between the Dirac and Majorana cases. We find that the MVA method, compared to the more common CC method, can greatly enhance the discovery and discrimination limits. Two benchmark points with sterile neutrino mass m N =20 GeV and 50 GeV are tested. For an integrated luminosity of 3000 fb^-1, sterile neutrinos can be found with 5σ significance if heavy-to-light neutrino mixings ｜U_（Ne）｜^2~｜U_（Nμ）｜^2~10^-6, while Majorana vs. Dirac discrimination can be reached if at least one of the mixings is of order 10^-5.展开更多
In this paper, we present a gauge inflation model based on the orbifold M4×S1/Z2 with non-Abelian SU（2） gauge symmetry, which is probably the simplest model in this category. As the inflaton potential is fully ...In this paper, we present a gauge inflation model based on the orbifold M4×S1/Z2 with non-Abelian SU（2） gauge symmetry, which is probably the simplest model in this category. As the inflaton potential is fully radiatively generated exclusively by gauge self-interactions, the model is predictive; thus, it is protected by gauge symmetry itself, without the introduction of any additional matter fields or arbitrary interactions. We show that the model fully agrees with the recent cosmological observations within the controlled perturbative regime of gauge interactions, g4≤1/（2πRMP）, with the compactification radius（10 ≤ RMP ≤ 100）： the expected magnitude of the curvature perturbation power spectrum and the value of the corresponding spectral index are in perfect agreement with the recent observations. The model also predicts a large fraction of the gravitational waves, negligible nonGaussianity, and a sufficiently high reheating temperature.展开更多
基金support by FONDECYT(Chile)(1130599)supported in part by the NRF grant funded by the Korean government of the MEST(2016R1D1A1A02936965)
文摘The universality of the weak interactions can be tested in semileptonic b→c transitions,and in particular in the ratios R（D＊） ≡ Γ（B → D（＊）τν）/Γ（B → D＊lν）（where 1 = μ or e）.Due to the recent differences between the experimental measurements of these observables by Ba Bar,Belle and LHCb on the one hand and the Standard Model predicted values on the other hand,we study the predicted ratios R（D＊）=Γ（B→D＊τ＋＂missing＂）/Γ（B→D（＊）lν）in scenarios with an additional sterile heavy neutrino of mass ～1 Ge V.Further,we evaluate the newly defined ratio R（0）≡Γ（B→τ＋＂missing＂）/Γ（B→μν） in such scenarios,in view of the future possibilities of measuring the quantity at Belle-Ⅱ.
基金Supported by the International Postdoctoral Exchange Fellowship Program(No.90 Document of OCPC,2015)the NRF grant funded by the Korean government of the MEST(No.2016R1D1A1A02936965)+2 种基金Chile grants Fondecyt No.1130617Conicyt ACT 1406PIA/Basal FB0821
文摘We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of W^±→e^±e^±μ ν and μ^±^±e ν at the 14 TeV LHC. The discovery and exclusion limits for sterile neutrinos are shown using both the Cut-and-Count（CC） and Multi-Variate Analysis（MVA） methods. We also discriminate between Dirac and Majorana sterile neutrinos by exploiting a set of kinematic observables which differ between the Dirac and Majorana cases. We find that the MVA method, compared to the more common CC method, can greatly enhance the discovery and discrimination limits. Two benchmark points with sterile neutrino mass m N =20 GeV and 50 GeV are tested. For an integrated luminosity of 3000 fb^-1, sterile neutrinos can be found with 5σ significance if heavy-to-light neutrino mixings ｜U_（Ne）｜^2~｜U_（Nμ）｜^2~10^-6, while Majorana vs. Dirac discrimination can be reached if at least one of the mixings is of order 10^-5.
基金supported in part by the Basic Science Research Program through the National Research Foundation of Korea Research Grant 2016R1D1A1B03930408a TJ Park Science Fellowship of the POSCO TJ Park Foundationsupported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(2016R1A2B2016112)
文摘In this paper, we present a gauge inflation model based on the orbifold M4×S1/Z2 with non-Abelian SU（2） gauge symmetry, which is probably the simplest model in this category. As the inflaton potential is fully radiatively generated exclusively by gauge self-interactions, the model is predictive; thus, it is protected by gauge symmetry itself, without the introduction of any additional matter fields or arbitrary interactions. We show that the model fully agrees with the recent cosmological observations within the controlled perturbative regime of gauge interactions, g4≤1/（2πRMP）, with the compactification radius（10 ≤ RMP ≤ 100）： the expected magnitude of the curvature perturbation power spectrum and the value of the corresponding spectral index are in perfect agreement with the recent observations. The model also predicts a large fraction of the gravitational waves, negligible nonGaussianity, and a sufficiently high reheating temperature.
