CP violation with beautiful baryons
CP violation with beautiful baryons
复制标题
美丽重子的 CP 破坏
DOI：
10.1007/bf01589716
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
I. Dunietz
中科院分区：
文献类型：
--
作者：
I. Dunietz
摘要当衰变过程与其电荷共轭伙伴进行比较时，CP 破坏可以在粲或底部重子模式中进行研究。它可以表现为速率不对称性以及其他衰减参数的研究。与传统的 B0 模式相比，观察重子模式的 CP 破坏既不需要标记也不需要时间依赖性。底部重子的多种模式有可能在标准模型中表现出大的CP破坏效应。对于具有 aD0 的模式来说，这些影响可能很大，这可以在最终状态中看到，也可以从 aD0 馈送
$$\bar D^0 $$
。例如，Λb→ΛCP0 与
$$\bar \Lambda _b \to \bar \Lambda D_{CP}^0 $$
过程可能会显示出相当大的 CP 违规。这里 DCPo 表示 D0 的 CP 本征态，其出现频率为百分之几。六个相关过程，如Λb→ΛD0，
$$\Lambda _b \到 \Lambda \bar D^0 $$
,Λb→ΛCP0 及其电荷共轭对应物可以提取 ψ，这是酉三角形中最有问题的角度，通常用 Bs→ρ0KS 不对称性来探测。这里D0和D−0通过它们带电的kaon或轻子来识别。我们预测 B(Λb→ΛD0)∼10−5，因此 B(Λb→ΛCP0)∼10−7。在有利的情况下，CP 破坏可能会发生在百分之几十的水平。因此 102–103Λb→ΛCP0 衰变开始探测 phi。表中列出了许多其他模式，其典型分支比为 10−5–10−6 水平，具有较高的检测效率（与 DCP0 相比），并且具有潜在的较大 CP 破坏效应，例如 Ξb0→ΛΨ、Λphi、ΛK*0； Ξb-→ΛK(*)-，Ξ-Ks，Ξ-K*0，Ωb-→Ξ-φ，Ξ-ρ0，ΛK(*)-，ΩKs，Ω-K*0。
AbstractCP violation can be studied in modes of charmed or bottom baryons when a decay process is compared with its charge-conjugated partner. It can show up as a rate asymmetry and in a study of other decay parameters. Neither tagging nor time-dependences are required to observeCP violation with modes of baryons, in contrast to the conventionalB0 modes. Numerous modes of bottom baryons have the potential to show largeCP-violating effects within the Standard Model. Those effects can be substantial for modes with aD0, which is seen in a final state that can also be fed from a
$$\bar D^0 $$
. For instance, a comparison of theΛb→ΛCP0 with the
$$\bar \Lambda _b \to \bar \Lambda D_{CP}^0 $$
process can show sizeableCP violation. HereDCPo denotesCP eigenstates ofD0, which occur at a few percent. Six related processes, such asΛb→ΛD0,
$$\Lambda _b \to \Lambda \bar D^0 $$
,Λb→ΛCP0, and their charge-conjugated counterparts, can extract ϕ, which is the most problematic angle of the unitarity triangle and which is conventionally probed with theBs→ρ0KS asymmetry. HereD0 andD−0 are identified by their charged kaon or lepton. We predictB(Λb→ΛD0)∼10−5, thusB(Λb→ΛCP0)∼10−7. Under favourable circumstances,CP violation can occur at the few tens of percent level. Thus 102–103Λb→ΛCP0 decays start probing ϕ. Tables list many additional modes with typical branching ratios at the 10−5–10−6 level, with large detection efficiencies (in contrast to theDCP0), and with potentially largeCP-violating effects, such as Ξb0→ΛΨ, Λϕ, ΛK*0; Ξb−→ΛK(*)−, Ξ−Ks, Ξ−K*0, Ωb−→Ξ−φ, Ξ−ρ0, ΛK(*)−, ΩKs, Ω−K*0.