New Insights into Missing Transverse Momentum in Proton-Proton Collisions

Recent measurements conducted by the ATLAS Collaboration have provided new insights into the behavior of events with missing transverse momentum in proton-proton collisions at a center-of-mass energy of 13 TeV. The study, titled "Differential cross-sections for events with missing transverse momentum and jets measured with the ATLAS detector in 13 TeV proton-proton collisions," was submitted on March 5, 2024, and revised on September 3, 2024.

The research focuses on the differential cross-sections for the production of events that exhibit missing transverse momentum alongside jets. Utilizing an integrated luminosity of 140 fb$^{-1}$, the ATLAS detector has enabled detailed measurements of dijet distributions, particularly in regions where vector-boson fusion processes are enhanced.

The findings indicate that the measurements align closely with Standard Model predictions, with the exception of the dijet invariant mass distribution. Additionally, the study includes auxiliary measurements of the hadronic system that recoils against isolated leptons and photons within the same phase space.

One significant aspect of this research is the derivation of ratios between the measured distributions, which helps mitigate some of the major systematic uncertainties and modeling effects. These measurements are particularly sensitive to new phenomena, providing a framework for setting constraints on various phenomenological models. Notably, the results were compared with two common Dark Matter models, revealing that the constraints derived from this measurement are comparable to those established by dedicated detector-level searches.

This research not only enhances the understanding of high-energy particle interactions but also contributes to the broader search for new physics beyond the Standard Model. The complete findings can be accessed in the paper published in JHEP 08 (2024) 223, and further details are available at arXiv:2403.02793.