Takeshi Nihei

New cosmological and experimental constraints on the CMSSM

We analyze the implications of several recent cosmological and experimental measurements for the mass spectra of the Constrained MSSM (CMSSM). We compute the relic abundance of the neutralino and compare the new cosmologically expected and excluded mass ranges with those ruled out by the final LEP bounds on the lightest chargino and Higgs masses, with those excluded by current experimental values of BR(B→Xsγ), and with those favored by the recent measurement of the anomalous magnetic moment of the muon. We find that for tan β45 there remains relatively little room for the mass spectra to be consistent with the interplay of the several constraints. On the other hand, at larger values of tan β the decreasing mass of the pseudoscalar Higgs gives rise to a wide resonance in the neutralino WIMP pair-annihilation, whose position depends on the ratio of top and bottom quark masses. As a consequence, the cosmologically expected regions consistent with other constraints often grow significantly and generally shift towards superpartner masses in the TeV range.

Effect of RRRR dimension five operator on the proton decay in the minimal SU(5) SUGRA GUT model

We reanalyze the proton decay in the minimal SU(5) SUGRA GUT model. Unlike previous analyses, we take into account a Higgsino dressing diagram of dimension 5 operator with right-handed matter fields (

Exact Cross Sections for the Neutralino-Slepton Coannihilation

RRRR

Upper and Lower Limits on Neutralino WIMP Mass and Spin–Independent Scattering Cross Section, and Impact of New (g−2)μ Measurement

operator). It is shown that this diagram gives a dominant contribution for

Exact Cross Sections for the Neutralino WIMP Pair-Annihilation

p\to K^+\bar{\nu}_\tau

Observational constraints on the interacting Ricci dark energy model

over that from

Towards an accurate calculation of the neutralino relic density

LLLL

Neutralino dark matter in brane world cosmology

operator, and decay rate of this mode can be comparable with that of

Effect of supersymmetric CP phases on the B→Xsγ and B→Xsl+l− decays in the minimal supergravity model

p\to K^+\bar{\nu}_\mu

Light wino dark matter in brane world cosmology

which is dominated by the