标题： X650 $\to$ ZZ/WW/H125H95/A450Z/$γγ$ -- $J=1$, $J=2$, 窄或宽的共振？ 显示英文标题

标题： X650 $\to$ ZZ/WW/H125H95/A450Z/$γγ$ -- $J=1$, $J=2$, narrow or wide resonance?

摘要： 在ICHEP 2024上，CMS发表了RUN2关于ZZ->4轻子的结果，并得出结论，没有证据表明存在一个标量共振H650衰变为ZZ，ATLAS也通过优化用于标量粒子的MVA分析得出了同样的结论。 由于该共振被ATLAS在Cut Based Analysis中指示为ZZ，在三种其他模式中：WW和h95h125由CMS指示，ttZ由ATLAS指示，因此本文试图理解这些明显的矛盾。 我们的结论是，对反应H650->ZZ的严格选择不仅减少了信号，也减少了背景，从而降低了其统计显著性。 这种行为的一个合理解释是，这些选择对于通过VBF过程产生并衰变为ZZ且角分布类似于Drell Yan背景的自旋2粒子来说是不充分的。 如果属实，我们根据Georgi Machacek模型对各种发现的描述需要进行深入修订，这在本说明中进行了尝试。 提出了一种场景，其中T690作为自旋2的窄共振，自然容纳了WW/ZZ和h95h125衰变，而我们认为A450Z可能来自附近的H650共振。 我们提出了一种方案，其中标量共振被容纳在三个标量同位旋双态中，而T690、T450++、T375+和T350属于两个张量同位旋五重态。 在这个场景中，T690可能是一个与标准模型背景相互作用的窄共振，正如其在双光子模式中的观察所证实的那样，这加强了Kaluza Klein引力子的解释。 如果如ATLAS和CMS所指示的，T690耦合到e+e-，这个场景将对未来$e^+e^-$对撞机做出戏剧性的预测。 显示英文摘要

摘要： At ICHEP 2024 CMS has published RUN2 results for ZZ->4 leptons and reached the conclusion that there is no evidence for a scalar resonance H650 decaying into ZZ, as was also concluded by ATLAS using an MVA analysis optimised for a scalar particle. Since this resonance is indicated into ZZ by ATLAS in a Cut Based Analysis and into three other modes: WW and h95h125 by CMS, ttZ by ATLAS , the present paper is an attempt to understand these apparent contradictions. Our conclusion is that strict selections for the reaction H650->ZZ cut as much into the signal than into the background, therefore reducing its statistical significance. A plausible interpretation of this behaviour is that these selections are inadequate for a spin 2 particle produced by the VBF process and decaying into ZZ with an angular distribution similar to the Drell Yan background. If true, our description of the various findings in term of the Georgi Machacek model needs to be deeply revised, which is attempted in the present note. A scenario with T690 as a spin 2 narrow resonance is presented which naturally accommodates WW/ZZ and h95h125 decays, while we suggest that A450Z could come from a H650 nearby resonance. We propose a scheme in which scalar resonances are accommodated in three scalar isodoublets, while T690, T450++, T375+ and T350 belong to two tensor isoquintuplets. In this scenario, T690 could be a narrow resonance which interferes with the SM background, as confirmed by its observation in the two photon mode, reinforcing a Kaluza Klein graviton interpretation. If, as indicated by ATLAS and CMS, T690 couples to e+e-, this scenario leads to a dramatic prediction for future $e^+e^-$ colliders.