Establishing <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>C</mml:mi> <mml:mi>P</mml:mi> </mml:math> Violation in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>b</mml:mi> </mml:math> -Baryon Decays
Jia-Jie Han, Ji-Xin Yu, Ya Li, Hsiang-nan Li, Jian-Peng Wang, Zhen-Jun Xiao, Fu-Sheng Yu
Abstract
It is a long-standing puzzle why the CP violation (CPV) in the baryon system has not yet been definitively established as in the meson one. We demonstrate that individual partial-wave CPV in the Λ_{b}→pπ^{-} and pK^{-} decays can exceed 10%, but the destruction between the partial waves (the suppression by the small partial-wave weight) results in a small net direct CPV in the former (the latter) as measured currently. Our finding highlights the different dynamics responsible for CPVs in baryon and meson decays. We propose to probe the CPV observables associated with the angular distributions of the Λ_{b}→pa_{1}(1260), pK_{1}(1270) decay products, which are large enough for being identified experimentally.