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精确测量 e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-} 截面的质量中心能量从值到4.95 GeV
M Ablikim1, M N Achasov2, P Adlarson3
1Institute of High Energy Physics, Beijing 100049, People's Republic of China.
Physical review letters
|October 28, 2023
概括
研究人员精确地测量了波恩的截面,用于e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-}过程. 观察到两个新的共振结构,并在能量依赖的横截面中进行了表征.
科学领域:
- 粒子物理学 粒子物理学
- 高能物理 高能物理
- 量子色态动力学 量子色态动力学
背景情况:
- 对e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-}过程的研究为标准模型中的复杂相互作用提供了洞察力.
- 了解D_{s}^{*+}D_{s}^{*-}共振的特性对于完善粒子相互作用的理论模型至关重要.
研究的目的:
- 为了第一次精确测量e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-}过程的波恩截面.
- 为了研究和描述测量的横截面内的共振结构.
- 为了确定观察到的共振结构的质量和宽度.
主要方法:
- 使用半包容方法,采用北京电子正子加速器BESIII探测器收集的数据.
- 分析了从值到4.95 GeV的质量中心能量数据样本.
- 采用一个与三个布雷特-维格纳振幅和一个相空间振幅的连贯和值相适应的能量依赖横截面.
主要成果:
- 对于e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-}的波恩截面,其测量精度非常高.
- 在4.2 GeV和4.4 GeV附近观察到两个显著的共振结构.
- 这些结构的质量和宽度分别为 (4186.8±8.7±30) MeV/c^{2},宽度为 (55±15±53) MeV,和 (4414.6±3.4±6.1) MeV/c^{2},宽度为 (122.5±7.5±8.1) MeV.
- 还确定了大约4.79 GeV的第三个共振结构,需要第三个布雷特-维格纳振幅来描述.
结论:
- 精确测量波恩截面提供了有价值的数据,以了解e^{+}e^{-}→D_{s}^{*+}D_{s}^{*-}过程.
- 观察到的共振结构为重夸克状态的光谱提供了新的见解.
- 这些发现需要对这些新发现的共振的性质和特性进行进一步的理论研究.
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