Measurements of weak decay asymmetries of Lambda(+)(c) -> pK(S)(0), Lambda pi(+), Sigma(+)pi(0), and Sigma(0)pi(+)

Abstract

Using e(+)e(-) -> Lambda(+)(c)(Lambda) over bar (-)(c). production from a 567 pb(-1) data sample collected by BESIII at 4.6 GeV, a full angular analysis is carried out simultaneously on the four decay modes of Lambda(+)(c) -> pK(S)(0), Lambda pi(+), Sigma(+)pi(0), and Sigma(0)pi(+). For the first time, the Lambda(+)(c) transverse polarization is studied in unpolarized e(+)e(-) collisions, where a nonzero effect is observed with a statistical significance of 2.1 sigma. The decay asymmetry parameters of the Lambda(+)(c) weak hadronic decays into pK(S)(0), Lambda pi(+), Sigma(+)pi(0), and Sigma(0)pi(+) are measured to be 0.18 +/- 0.43(stat) +/- 0.14(syst), -0.80 +/- 0.11(stat) +/- 0.02(syst), -0.57 +/- 0.10(stat) +/- 0.07(syst), and -0.73 +/- 0.17(stat) +/- 0.07(syst), respectively. In comparison with previous results, the measurements for the Lambda pi(+) and Sigma(+)pi(0) modes are consistent but with improved precision, while the parameters for the pK(S)(0) and Sigma(+)pi(0) modes are measured for the first time.