Shinya Kanemura

New physics effect on the Higgs self-coupling

One-loop corrections to the self-coupling constant of the lightest CP-even Higgs boson are studied in the two Higgs doublet model. After renormalization is performed, quartic contributions of heavy particles mass can appear in the effective coupling. We find that these non-decoupling effects can yield O(100)% deviations from the Standard Model prediction, even when all the other couplings of the lightest Higgs boson to gauge bosons and fermions are in good agreement with the Standard Model.

Phenomenology of Higgs bosons in the Zee model

To generate small neutrino masses radiatively, the Zee model introduces two Higgs doublets and one weak-singlet charged Higgs boson to its Higgs sector. From analyzing the renormalization group equations, we determine the possible range of the lightest CP-even Higgs boson (h) mass and the Higgs boson self-couplings as a function of the cutoff scale beyond which either some of the coupling constants are strong enough to invalidate the perturbative analysis or the stability of the electroweak vacuum is no longer guaranteed. Using the results obtained from the above analysis, we find that the singlet charged Higgs boson can significantly modify the partial decay width of

Thermodynamic Gross-Neveu model in a constant electromagnetic field

\stackrel{\ensuremath{\rightarrow}}{h}\ensuremath{\gamma}\ensuremath{\gamma}

Single charged Higgs boson production at next generation linear colliders

via radiative corrections, and its collider phenomenology can also be drastically different from that of the charged Higgs bosons in the usual two-Higgs-doublet models.

Single charged Higgs boson production in polarized photon collisions and the probe of new physics

We analyze the effective potential of the D-dimensional thermodynamic Gross-Neveu model (defined by large-N leading order, 2 ⩽ D < 4) in a constant electromagnetic field (E · B = 0). The potential is derived from a thermal analogy of the worldline formalism. In the magnetic case, the potential is expressed in terms of a discretized momentum sum instead of a continuum momentum integral, and it reproduces the known critical values of μ and T in the continuum limit. In the electric case, chiral symmetry is restored at finite T (with arbitrary μ) against instability of the fermion vacuum. An electromagnetic duality is pointed out as well. Phase diagrams are obtained in both cases.

Nondecoupling effects of Higgs bosons on e + e − → W L + W L − in the two-doublet model

We study the single production of charged Higgs bosons in e+e- collisions, chiefly in the Minimal Supersymmetric Standard Model. Our analysis complements foregoing studies of the pair production channel especially in regions where the kinematic constraint suppresses pair production. We present cross sections relevant to experiments at the next generation linear colliders and some brief discussions of their phenomenology. Our analysis shows that the single production is a useful alternative channel for studying the phenomenology of charged Higgs bosons, and there are regions of parameter space where it is accessible beyond the kinematic limit for pair production.

APPROACH TO D-DIMENSIONAL GROSS–NEVEU MODEL AT FINITE TEMPERATURE AND CURVATURE

We study single charged Higgs boson production in photon-photon collisions as a probe of the new dynamics of Higgs interactions. This is particularly important when the mass

ON PHASE DIAGRAM OF GROSS-NEVEU MODEL AT FINITE TEMPERATURE, DENSITY AND CONSTANT CURVATURE

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Heavy charged Higgs boson production at next generation

of charged Higgs bosons

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