CP-violating asymmetry in chargino decay into neutralino and W boson

Abstract In the MSSM with complex parameters, loop corrections to χ ˜ i ± → χ ˜ j 0 W ± lead to a CP violating asymmetry A CP = ( Γ ( χ ˜ i + → χ ˜ j 0 W + ) − Γ ( χ ˜ i − → χ ˜ j 0 W − ) ) / ( Γ ( χ ˜ i + → χ ˜ j 0 W + ) + Γ ( χ ˜ i − → χ ˜ j 0 W − ) ) . We calculate this asymmetry at full one-loop level. We perform a detailed numerical analysis for χ ˜ 1 ± → χ ˜ 1 0 W ± and χ ˜ 2 ± → χ ˜ 1 0 W ± analyzing the dependence on the parameters and phases involved. Asymmetries of several percent are obtained. We also discuss the feasibility of measuring these asymmetries at LHC.