相关论文: Top-Squark Study at a Future e^+e^- Linear Collide…
A stable neutralino $\chi_1^0$, assumed to be the lightest supersymmetric particle, is a favored particle physics candidate for the cosmological Dark Matter. We study co-annihilation of the lightest neutralino with the lighter scalar top…
The supersymmetric decays of the top quark into charged Higgs plus bottom, $\thb$, and into the supersymmetric partner of the top (${\wti u}_1$) plus the lightest neutralino (${\wti \chi}_1^0$), $\tstopneu$, are discussed within the…
We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in low energy supersymmetric models for the International Linear Collider energies. This includes the minimal…
In Supersymmetry with large $\tan\beta$ values, the lighter stau ($\tilde{\tau}_{1}$) may be lighter than the lightest chargino ($\tilde{\chi}^{\pm}_{1}$). The decay $\tilde{\chi}^{\pm}_{1} \to \tilde{\tau}^{\pm}_{1} \nu_{\tau}$, followed…
Once supersymmetric neutralinos $\tilde{\chi}^0$ are produced copiously at $e^+e^-$ linear colliders, their characteristics can be measured with high precision. In particular, the fundamental parameters in the gaugino/higgsino sector of the…
A search for the pair production of the lightest supersymmetric partner of the top quark ($\widetilde{\mathrm{t}}_1$) is presented. The search focuses on a compressed scenario where the mass difference between the top squark and the…
In most supersymmetric theories charginos, $\tilde{\chi}^\pm_{1,2}$, belong to the class of the lightest supersymmetric particles. The chargino system can be reconstructed completely in $e^+e^-$ collider experiments:…
A search for the pair production of the lightest supersymmetric partner of the top quark, the top squark ($\tilde{\mathrm{t}}_1$), is presented. The search targets the four-body decay of the $\tilde{\mathrm{t}}_1$, which is preferred when…
We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in supersymmetric models with grand unification. We consider models wherein the standard model gauge group…
Decays of the lightest neutralino are studied in $R_p$-violating models, with operators $\lambda^\prime L Q D^c$ and $\lambda L L E^c$ involving third-generation matter fields and with dominant $\lambda^\prime$ and $\lambda$ couplings.…
We analyze higher order decay modes of the lightest top squark $\tilde{t}_1$ in the Minimal Supersymmetric extension of the Standard Model (MSSM), where the lightest SUSY particle (LSP) is assumed to be the neutralino $\chi_1^0$. For small…
In most supersymmetric theories, charginos $\tilde{\chi}^\pm_{1,2}$ belong to the class of the lightest supersymmetric particles and they are easy to observe at e^+e^- colliders. By measuring the total cross sections and the left-right…
Approximately 438 pb-1 of e+e- data from the OPAL detector, taken with the LEP collider running at centre-of-mass energies of 192-209 Gev, are analyzed to search for evidence of chargino pair production, e+e- -> tilde chi^+_1 tilde chi^-_1,…
We consider neutralino production and decay e^+e^ --> chi^0_i chi^0_j, chi^0_j --> chi^0_1 f \bar{f} at a linear collider with transverse e^+ and e^- beam polarization. We propose CP asymmetries by means of the azimuthal distribution of the…
The lighter chargino pair production ($e^+e^- \to \tilde{\chi}^{+}_{1} \tilde{\chi}^{-}_{1}$) is one of key processes for determination of supersymmetric parameters at a linear collider. If $\tan\beta$ is a large value, the lighter stau…
Charginos $\tilde{\chi}^\pm$ and neutralinos $\tilde{\chi}^0$ in supersymmetric theories can be produced copiously at $e^+e^-$ colliders and their properties can be measured with high accuracy. Consecutively to the chargino system, in which…
In supersymmetric theories, the top quark can decay into its scalar partner plus a neutralino, with an appreciable rate. We calculate the $O(\alpha_s)$ QCD corrections to this decay mode in the minimal supersymmetric extension of the…
We study the production processes e^+ e^- -> chi^+_i chi^-_j, i,j=1,2, and e^+ e^- -> chi^0_m chi^0_n, m,n=1,...,4, working out the advantages of polarizing both beams. For e^+ e^- -> chi^+_1 chi^-_1 with chi^-_1 -> chi^0_1 e^- nu and e^+…
Charginos $\chi_1^\pm$ are expected to be the lightest observable supersymmetric particles in many supersymmetric models. We present a procedure which will allow to determine the chargino mixing angles and, subsequently, the fundamental…
In the Minimal Supersymmetric Standard Model, the cross section for the associated production of the lightest neutral Higgs boson with the lightest top squark pairs can be rather substantial at high energies. We summarize the properties of…