论文标题
$ r $测量和QCD研究在未来超级$τ-c $工厂
$R$ measurement and QCD studies at future super $τ-c$ factory
论文作者
论文摘要
我们在低能范围内审查$ r $ $ $测量和QCD研究的状态，讨论超级$τ-$ charm工厂的前景，价格为$ 2-7 $ GEV。凭借高发光性$ e^+e^ - $ collider，统计数据不再是$ r $测量的问题，精度为$ 2 \％$甚至更好，这将导致统计，这将导致降低对QED的不确定性贡献的不确定性，以使QED贡献coupl coupl coupl coupl coupl coupl count coupl count coupl count coupl cont count coupl cont count count cont count coupl under unance untans $δα_{测量强耦合常数$α_s$和符号夸克质量；改善重型夏娃状的共振参数的测量。 $ 2-3 $ GEV中的巨大数据样本将使研究$ρ$，$ω$和$ ϕ $或Exotic $ y（2175）$的激发态成为可能。测量介子和重子的电磁形状；并测量HADRON的碎裂功能。
We review status of $R$ measurement and QCD studies at low energy range, discuss prospects for a super $τ-$charm factory in $2-7$ GeV. With a high-luminosity $e^+e^-$ collider, statistics are no longer problem for $R$ measurement and a precision of $2\%$ or even better is foreseen, that will lead to bring down the uncertainty of hadronic contribution to the QED running coupling constant $Δα_{had}$ and the anomalous magnetic moment of the muon ($a_μ$); measure the strong coupling constant $α_s$ and the charm quark mass; improve the measurement of the resonance parameters of heavy charmonia. Huge data samples in $2-3$ GeV will make it possible to study excited states of $ρ$, $ω$ and $ϕ$, or exotic $Y(2175)$; measure electromagnetic form factor of mesons and baryons; and measure fragmentation functions of hadrons.
