Long-lived Charginos in the Focus-point Region of the MSSM Parameter Space

We analyse the possibility to get light long-lived charginos within the framework of the MSSM with gravity mediated SUSY breaking. We find out that this possibility can be realized in the so-called focus-point region of parameter space. The mass degeneracy of higgsino-like chargino and two higgsino-like neutralinos is the necessary condition for a long lifetime. It requires the fine-tuning of parameters, but being a single additional constraint in the whole parameter space it can be fulfilled in the Constrained MSSM along the border line where radiative electroweak symmetry breaking fails. In a narrow band close to the border line the charginos are long-lived particles. The cross-sections of their production and co-production at the LHC via electroweak interaction reach a few tenth of pb.Comment: LaTeX, 11 pages, 11 eps figure

Production of Long-Lived Sleptons at LHC

We analyse the MSSM parameter space and discuss the narrow band near the so-called co-annihilation region where sleptons may be long-lived particles. This region is consistent with the WMAP restrictions on the Dark matter and depends on the value of $\tan\beta$. In this region staus are long-lived and may go through the detector. Due to a relatively small mass (150 $\div$ 850 GeV) their production cross-section at LHC may reach a few % pb.Comment: LaTex, 8 pages, 6 eps figure

A gobal fit to the anomalous magnetic moment, Higgs limit and b->s gamma in the constrained MSSM

New data on the anomalous magnetic moment of the muon together with the b->s gamma decay rate and Higgs limits are considered within the supergravity inspired constrained minimal supersymmetric model. We perform a global statistical chi2 analysis of these data and show that the allowed region of parameter space is bounded from below by the Higgs limit, which depends on the trilinear coupling and from above by the anomalous magnetic moment.Comment: 3 pages, To appear in Proc. of SUSY01, Dubna (Russia

The b->sgamma rate and Higgs boson limits in the Constrained Minimal Supersymmetric Model

New NLO b->sgamma calculations have become available using resummed radiative corrections. Using these calculations we perform a global fit of the supergravity inspired constrained minimal supersymmetric model (CMSSM). We find that the resummed calculations show similar constraints as the LO calculations, namely that only with a relatively heavy supersymmetric mass spectrum of the order of 1 TeV the b-\tau Yukawa unification and the b->sgamma rate can coexist in the large tanb scenario. The resummed b->sgamma calculations are found to reduce the renormalization scale uncertainty considerably. The low tanb scenario is excluded by the present Higgs limits from LEP II. The constraint from the Higgs limit in the $m_0,m_{1/2}$ plane is severe, if the trilinear coupling A_0 at the GUT scale is fixed to zero, but is considerably reduced for $A_0\le -2m_0$. The relatively heavy SUSY spectrum required by \besg corresponds to a Higgs mass of m_h=119\pm 1~ (stop masses)}\pm 2~(theory)~\pm~3 (top mass) GeV in the CMSSM.Comment: latex + 7 eps figs, 14 pages, final version to be published in EPJ

Spectral Analysis of Multi-dimensional Self-similar Markov Processes

In this paper we consider a discrete scale invariant (DSI) process $\{X(t), t\in {\bf R^+}\}$ with scale $l>1$. We consider to have some fix number of observations in every scale, say $T$, and to get our samples at discrete points $\alpha^k, k\in {\bf W}$ where $\alpha$ is obtained by the equality $l=\alpha^T$ and ${\bf W}=\{0, 1,...\}$. So we provide a discrete time scale invariant (DT-SI) process $X(\cdot)$ with parameter space $\{\alpha^k, k\in {\bf W}\}$. We find the spectral representation of the covariance function of such DT-SI process. By providing harmonic like representation of multi-dimensional self-similar processes, spectral density function of them are presented. We assume that the process $\{X(t), t\in {\bf R^+}\}$ is also Markov in the wide sense and provide a discrete time scale invariant Markov (DT-SIM) process with the above scheme of sampling. We present an example of DT-SIM process, simple Brownian motion, by the above sampling scheme and verify our results. Finally we find the spectral density matrix of such DT-SIM process and show that its associated $T$-dimensional self-similar Markov process is fully specified by $\{R_{j}^H(1),R_{j}^H(0),j=0, 1,..., T-1\}$ where $R_j^H(\tau)$ is the covariance function of $j$th and $(j+\tau)$th observations of the process.Comment: 16 page