Measurements of weak decay asymmetries of Lambda(+)(c) -> pK(S)(0), Lambda pi(+), Sigma(+)pi(0), and Sigma(0)pi(+)
Citation
Ablikim, M., Achasov, M. N., Adlarson, P., Ahmed, S., Albrecht, M., Alekseev, M., ... & Kurth, M. G. (2019). Measurements of weak decay asymmetries of Λ c+→ p K s 0, Λ π+, Σ+ π 0, and Σ 0 π+. Physical Review D, 100(7), 072004.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.
