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arXiv 1602.00907hep-phnucl-th
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ρ介子的半径由其衰变常数确定

The radius of the rho meson determined from its decay constant

A. F. Krutov, R. G. Polezhaev, V. E. Troitsky

摘要:

本文提出了一个描述π介子和ρ介子电弱性质的统一模型。利用定域算符矩阵元的相对论参数化的一般方法,在总角动量情况下对非对角项作了调整,我们用自由组分夸克的相同参数计算了ρ介子轻子衰变常数f_rho,这些参数保证了以前对π介子的唯一好结果。唯一的自由参数,表征夸克相互作用,其中包括额外的自旋-自旋贡献,因此不同于$π$ -介子的情况下,是固定的匹配的衰变常数,其实验值。计算出均方电荷半径,<r^2_rho>=(0.56+-0.04)fm^2。这一结果证实了在ρ介子情况下,强子的电磁半径与强半径相等的猜想。

英文摘要:

We present a unified model describing electroweak properties of the pi and rho mesons. Using a general method of relativistic parametrization of matrix elements of local operators, adjusted for the nondiagonal in total angular momentum case, we calculate the rho-meson lepton-decay constant f_rho using the same parameters of free constituent quarks that have ensured exclusively good results for the pi meson previously. The only free parameter, characterizing quark interactions, which include additional spin-spin contribution and hence differ from the $π$-meson case, is fixed by matching the decay constant to its experimental value. The mean square charge radius is calculated, <r^2_rho>=(0.56+-0.04) fm^2. This result verifies, for the rho-meson case, the conjecture of equality between electromagnetic and strong radii of hadrons tested previously for proton, pi and K mesons.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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