On the Effects of Elementary and Bound State Fields on Vacuum Stability in $t\bar{t}$ Production at the LHC

The recent report by the CMS Collaboration on the excess of top and anti-top pair production is examined with regard to the improvement of vacuum stability under two simple scenarios: one with the existence of toponium $({\eta }_t)$, and the other with an additional elementary field $(\mathrm{\Psi })$. In both cases, the values of each coupling constant are restricted by the Multicritical Point Principle (MPP). Two scenarios are considered. The first incorporates the effect of toponium $({\eta }_t)$, inspired by the Bardeen-Hill-Lindner (BHL) framework, and the second embeds $\mathrm{\Psi }$ into the Standard Model (SM) as a minimal model close to an inert doublet model. From these analyses, it is found that toponium cannot satisfy the MPP, whereas the additional elementary field can.