16229442
Proposal for generalised supersymmetry Les Houches Accord for see-saw models and PDG numbering scheme
The SUSY Les Houches Accord (SLHA) 2 extended the first SLHA to include various generalisations of the Minimal Supersymmetric Standard Model (MSSM) as well as its simplest next-to-minimal version. Here, we propose further extensions to it, to include the most general and well-established see-saw descriptions (types I/II/III, inverse, and linear) in both an effective and a simple gauged extension of the MSSM framework. In addition, we generalise the PDG numbering scheme to reflect the properties of the particles.
55200110
Flavoured co-annihilation
In minimal supergravity (mSUGRA) or CMSSM, one of the main co-annihilating partners of the neutralino is the lightest stau, $\tilde{\tau}_1$. In the presence of flavour violation in the right-handed sector, the co-annihilating partner would be a flavour mixed state. The flavour effect is two-fold: (a) It changes the mass of $\tilde{\tau}_{1}$, thus modifying the parameter space of the co-annihilation and (b) flavour violating scatterings could now contribute to the cross-sections in the early Universe. In fact, it is shown that for large enough δ~0.2, these processes would constitute the dominant channels in co-annihilation regions. The amount of flavour mixing permissible is constrained by flavour violating τ→μ or τ→e processes. For ΔRR mass insertions, the constraints from flavour violation are not strong enough in some regions of the parameter space due to partial cancellations in the amplitudes. In mSUGRA, the regions with cancelations within LFV amplitudes do not overlap with the regions of co-annihilations. In non-universal Higgs model (NUHM), however, these regions do overlap leading to significant flavoured co-annihilations. At the LHC and other colliders, these regions can constitute for interesting signals.
119124449
Inertial effect on spin–orbit coupling and spin transport
Abstract We theoretically study the renormalization of inertial effects on the spin dependent transport of conduction electrons in a semiconductor by taking into account the interband mixing on the basis of k → ⋅ p → perturbation theory. In our analysis, for the generation of spin current we have used the extended Drude model where the spin–orbit coupling plays an important role. We predict enhancement of the spin current resulting from the renormalized spin–orbit coupling effective in our model in cubic and non-cubic crystals. Attention has been paid to clarify the importance of gauge fields in the spin transport of this inertial system. A theoretical proposition of a perfect spin filter has been done through the Aharonov–Casher like phase corresponding to this inertial system. For a time dependent acceleration, effect of k → ⋅ p → perturbation on the spin current and spin polarization has also been addressed. Furthermore, achievement of a tunable source of polarized spin current through the non uniformity of the inertial spin–orbit coupling strength has also been discussed.