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优化O ((α_{s}^{2}) 对B工厂的独家双J/ψ生产进行校正
Wen-Long Sang1, Feng Feng2,3, Yu Jia2,4
1School of Physical Science and Technology, Southwest University, Chongqing 400700, China.
Physical review letters
|November 5, 2023
概括
研究人员计算了对e^{+}e^{-}→J/ψJ/ψ事件的O(α_{s}^{2}) 校正,发现它基本上是负的. 一个改进的框架预测了正面截面,使Belle 2的观测成为可能.
科学领域:
- 高能物理 高能物理
- 量子色态动力学 量子色态动力学
- 粒子物理学 粒子物理学
背景情况:
- 在B工厂观察e^{+}e^{-}→J/ψJ/ψ事件受到显著的负顺序-α_{s}校正的阻碍.
- 由于这些纠正,标准的非相对论QCD预测产生了非物理的负截面.
研究的目的:
- 第一次计算e^{+}e^{-}→J/ψJ/ψ生产的O(α_{s}^{2}) 校正.
- 通过实施改进的非相对论QCD分解框架来解决导致非物理预测的差异.
主要方法:
- 计算了下一个到下一个到领先的顺序 (NNLO) 的扰动性纠正.
- 将振幅分解为光子碎片化和非碎片化元件.
- 利用测量的J/ψ衰变常数来恢复特定的辐射和相对论纠正.
主要成果:
- NNLO的调整基本上是负的,这给标准预测带来了挑战.
- 改进的框架,包括碎片化和非碎片化片段,产生一个积极的横截面.
- 截面的最佳预测是 σ(e^{+}e^{-}→J/ψJ/ψ) =2.13_{-0.06}^{+0.30} fb 在 √s=10.58 GeV.
结论:
- 使用J/ψ衰变常数作为输入,可以准确预测碎片化诱导的生产率.
- 通过NNLO计算的非碎片幅度显示了正的O(α_{s}) 和O(α_{s}^{2}) 校正,并具有良好的收.
- 在Belle 2实验中观察这种独特的过程是有希望的,预计整合发光度为50ab-1.1.
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