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arXiv · 1510.03957

$CP$ Invariance Study of $J/ψ\toΛ\barΛ$ and $Λ$ Nonpleptonic Decays in Helicity Frame

Bin Zhong·Guangrui Liao
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Abstract

We present the joint helicity amplitudes for $J/ψ\to Λ\barΛ$, $Λ(\barΛ)$ decays to different final states in the helicity frame. Two observables to search for $CP$ violation in $J/ψ\toΛ\barΛ$ can be expressed with the information of helicity angles of baryon and antibaryon. Four decay parameters of $Λ$ and $\barΛ$, namely, $α_-,α_+,α_0$ and $\barα_0$, can be obtained with the joint helicity amplitude equations by the likelihood fit method. With the data sample of $10^{10}$ $J/ψ$ decays accumulated by BESIII, the precision of the measurements is estimated to be about $10^{-3}$.

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Bin Zhong, Guangrui Liao. 2016-02-29. $CP$ Invariance Study of $J/ψ\toΛ\barΛ$ and $Λ$ Nonpleptonic Decays in Helicity Frame. https://doi.org/10.5506/aphyspolb.46.2459

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