Study of $s\to d\nu\bar{\nu}$ rare hyperon decays within the standard model and new physics.

FCNC processes offer important tools to test the standard model, and to search for possible new physics. In this work, we investigate the $s\to d\nu\bar{\nu}$ rare hyperon decays within the standard model and beyond. The hadronic matrix elements, parametrized in terms of form factors, are calculated in the light-front approach. We find branching ratios for these rare hyperon decays range from $10^{-14}$ to $10^{-11}$ within the standard model. And after taking into account the contribution from the new physics, the generalized SUSY extension of the SM and the minimal 331 model, the decay widths for these channels can be enhanced by a factor of 2 and 7, respectively. Uncertainties are discussed.