论文标题
生产超级$ z $工厂的双重夸克
Production of double heavy quarkonium at super $Z$ factory
论文作者
论文摘要
在Color Singlet型号中，我们计算了Future Super $ Z $ FACTORY的双charmonia，Double Bostonia和Double $ b_c $ Meson的独家生产。两个重型Quarkonia或$ b_c $的s是两个s波群态（$^1S_0，〜^3S_1 $），或一个S-Wave和一个p波状态（$^1p_1，〜^3p_j〜（j = 0,1,1,2）$）。双charmonia的横截面中的前三个$ z^0 $传播通道为$ j/ψ+h_c，η_c+χ_{c2} $和$η_c+χ_{c0} $。对于双重底部，它们是$η_b+υ，υ+χ_ {b2} $和$υ+υ$。对于双$ b_c $ mesons，它们是$ b_c^{*+}+b_c^{* - } $，$ b_c^{*+}+χ_{bc2}^ - $，和$η_{bc}^+++++++++++++++b_c^{* - } $。双$ b_c $介子的横截面大约比双底尼尼亚的杂物大约一个数量级，并且比双charmonia的交叉阶段大两个数量级。为了使其对实验研究有所帮助，我们将总跨部分$σ$作为CM Energy $ \ sqrt {s} $，$σ$的功能，作为重新分布量表$μ$的函数，角度分布$dσ/dcosθ$和$ p_t $ p_t $ dressignion $ dent $ dtσ/dtσ/dtσ/dp_ {t} $。不确定性来自不同质量的重型夸克，提出了20％的校正。我们还发现，当1 \％$ M_z $ Energy损失时，初始状态辐射可以带来约30％的$ \ sim $ 40％的替补，并且当采用不同的潜在模型时，跨部门可以增加约2美元\ sim3 $ timple $ 2 \ sim3 $ timple，或者通过数量级减少。数值结果表明，它可能对实验观察不乐观，但是在FCC-EE中，它远未排除在FCC-EE，以及在$ Z $工厂模式下运行的CEPC。
Within the color singlet model, we calculate the exclusive production of double charmonia, double bottomonia, and double $B_c$ mesons at future super $Z$ factory. The two heavy quarkonia or $B_c$'s are either two S-wave Fock states ($^1S_0, ~^3S_1$), or one S-wave and one P-wave states ($^1P_1,~^3P_J~(J=0,1,2)$). The top three $Z^0$ propagated channels in cross sections for double charmonia are $J/ψ+h_c,η_c+χ_{c2}$, and $η_c+χ_{c0}$. For double bottomonia, they are $η_b+Υ, Υ+χ_{b2}$, and $Υ+Υ$. For double $B_c$ mesons, they are $B_c^{*+}+B_c^{*-}$,$B_c^{*+}+χ_{bc2}^-$, and $η_{bc}^++B_c^{*-}$. The cross sections of double $B_c$ mesons are roughly one order of magnitude larger than those of the double bottomonia, and two orders of magnitude larger than those of the double charmonia. To make it helpful for experimental study, we present the total cross sections $σ$ as functions of CM energy $\sqrt{s}$, $σ$ as functions of the renormalization scale $μ$, the angle distributions $dσ/dcosθ$, and the $p_T$ distributions $dσ/dp_{t}$. The uncertainties come from the varying masses of constituent heavy quarks bring up to 20% corrections. We also find that the initial state radiation can bring about 30%$\sim$40% suppresions when 1\%$m_Z$ energy is losing, and cross sections can increase by about $2\sim3$ times or decrease by an order of magnitude when adopting different potential models which becomes the major source of uncertainty. The numerical results show that it might be not optimistic for the experimental observation, but it is still far from excluded at the FCC-ee and also the CEPC running in the $Z$ factory mode.
