TeV scale seesaw from supersymmetric Higgs-lepton inflation and BICEP2

We discuss the physics resulting from the supersymmetric Higgs-lepton inflation model and the recent CMB B-mode observation by the BICEP2 experiment. The tensor-to-scalar ratio r=0.20+0.07-0.05 of the primordial fluctuations indicated by the CMB B-mode polarization is consistent with the prediction of this inflationary model for natural parameter values. A salient feature of the model is that it predicts the seesaw mass scale M from the amplitude of the tensor mode fluctuations. It is found that the 68% (95%) confidence level (CL) constraints from the BICEP2 experiment give 927 GeV < M < 1.62 TeV (751 GeV < M < 2.37 TeV) for 50 e-foldings and 391 GeV < M < 795 GeV (355 GeV < M < 1.10 TeV) for 60 e-foldings. In the type I seesaw case, the right-handed neutrinos in this mass range are elusive in collider experiments due to the small mixing angle. In the type III seesaw, in contrast, the heavy leptons will be within the reach of future experiments. We point out that a significant portion of the parameter region corresponding to the 68% CL of the BICEP2 experiment will be covered by the Large Hadron Collider experiments at 14 TeV.Comment: 6 pages, 1 figure. v2: a reference added. v3: typos fixe

Supersymmetric B-L inflation near the conformal coupling

We investigate a novel scenario of cosmological inflation in a gauged $B-L$ extended minimal supersymmetric Standard Model with R-symmetry. We use a noncanonical K\"{a}hler potential and a superpotential, both preserving the R-symmetry to construct a model of slow-roll inflation. The model is controlled by two real parameters: the nonminimal coupling $\xi$ that originates from the K\"{a}hler potential, and the breaking scale $v$ of the $U(1)_{B-L}$ symmetry. We compute the spectrum of the cosmological microwave background radiation and show that the prediction of the model fits well the recent Planck satellite observation for a wide range of the parameter space. We also find that the typical reheating temperature of the model is low enough to avoid the gravitino problem but nevertheless allows sufficient production of the baryon asymmetry if we take into account the effect of resonance enhancement. The model is free from cosmic strings that impose stringent constraints on generic $U(1)_{B-L}$ based scenarios, as in our scenario the $U(1)_{B-L}$ symmetry is broken from the onset.Comment: 9 pages, 4 figures, REVTeX 4.1. References added (v2). Comments added and typos corrected (v3

Reheating consistency condition on the classically conformal U(1)B−LU(1)_{B-L} Higgs inflation model

We revisit a cosmological scenario based on the classically conformal $U(1)_{B-L}$-extension of the Standard Model. Our focus is on the mechanism of reheating after inflation and the constraints on the model parameters. In this scenario, the inflationary dynamics is driven by the $U(1)_{B-L}$ Higgs field that is nonminimally coupled to gravity and breaks the $U(1)_{B-L}$ symmetry spontaneously as it acquires a vacuum expectation value through the Coleman-Weinberg mechanism. It is found that the reheating process proceeds stepwise, and as the decay channels of the $U(1)_{B-L}$ Higgs field are known, the reheating temperature is evaluated. The relation between the e-folding number of inflation and the reheating temperature provides a strong consistency condition on the model parameters, and we find that the recent cosmological data gives an upper bound on the $U(1)_{B-L}$ breaking scale $v_{BL}\lesssim 10^{12}$ GeV. The lower bound is $v_{BL}\gtrsim 10^6$ GeV, obtained as the condition for successful reheating in this model. The prediction for the cosmic microwave background (CMB) spectrum of this model fits extremely well with today's cosmological data. The model can be tested and is falsifiable by near future CMB observations, including the LiteBIRD and CMB-S4.Comment: 11 pages, 3 figures, Appendix B added, version to be publishe

臨床的クラウン－インプラント比の増加がインプラント周囲骨に及ぼす影響に関する実験的研究

広島大学(Hiroshima University)博士(歯学)Philosophy in Dental Sciencedoctora

Renormalization effects on the MSSM from a calculable model of a strongly coupled hidden sector

We investigate possible renormalization effects on the low-energy mass spectrum of the minimal supersymmetric standard model (MSSM), using a calculable model of strongly coupled hidden sector. We model the hidden sector by N=2 supersymmetric quantum chromodynamics with gauge group SU(2) x U(1) and N_f=2 matter hypermultiplets, perturbed by a Fayet-Iliopoulos term which breaks the supersymmetry down to N=0 on a metastable vacuum. In the hidden sector the Kahler potential is renormalized. Upon identifying a hidden sector modulus with the renormalization scale, and extrapolating to the strongly coupled regime using the Seiberg-Witten solution, the contribution from the hidden sector to the MSSM renormalization group flows is computed. For concreteness, we consider a model in which the renormalization effects are communicated to the MSSM sector via gauge mediation. In contrast to the perturbative toy examples of hidden sector renormalization studied in the literature, we find that our strongly coupled model exhibits rather intricate effects on the MSSM soft scalar mass spectrum, depending on how the hidden sector fields are coupled to the messenger fields. This model provides a concrete example in which the low-energy spectrum of MSSM particles that are expected to be accessible in collider experiments is obtained using strongly coupled hidden sector dynamics.Comment: 18 pages, 11 figures, REVTeX4. Essentially the published versio