"Cross-section limits - $M(X)/M(Y) = 0.21$" of "Search for resonant and nonresonant production of pairs of dijet resonances in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

The observed 95% CL upper limits on the product of the cross section, branching fraction, and acceptance for resonant production of paired dijet resonances decaying to a quark-gluon pair, with $M(X)/M(Y) = 0.21$. The corresponding expected limits and their variations at the 1 and 2 standard deviation levels are also shown. Limits are compared to predictions for a scalar diquark with couplings to pairs of up quarks, $y_{uu}$ = 0.4, and to pairs of vector-like quarks, $y_{χ}$ = 0.6.

针对衰变至夸克-胶子对的成对双喷注共振态（paired dijet resonances）的共振产生（resonant production）过程，其截面（cross section）、分支比（branching fraction）与接收度（acceptance）的乘积的观测95%置信度（Confidence Level, CL）上限，其中$M(X)/M(Y) = 0.21$。同时还展示了对应的预期极限及其在1倍和2倍标准偏差水平下的涨落范围。将上述极限与两类标量双夸克（scalar diquark）的理论预言进行了对比：一类是耦合至成对上夸克、耦合强度$y_{uu}=0.4$的标量双夸克；另一类是耦合至成对类矢量夸克（vector-like quarks）、耦合强度$y_{χ}=0.6$的标量双夸克。