2024

Search for heavy resonances in final states with four leptons and missing transverse momentum or jets in 𝑝𝑝 collisions at √𝒔 = 13 TeV with the ATLAS detector

Aad, G.; Aakvaag, E.; Abbott, B.; Abeling, K.; Abicht, N. J.; Abidi, S. H.; Aboulhorma, A.; Abramowicz, H.; Abreu, H.; Abulaiti, Y.; Acharya, B. S.; Adam Bourdarios, C.; Adamczyk, L.; Addepalli, S. V.; Addison, M. J.; Adelman, J.; Adiguzel, A.; Adye, T.; Affolder, A. A.; Afik, Y.; Agaras, M. N.; Agarwala, J.; Aggarwal, A.; Agheorghiesei, C.; Ahmad, A.; Ahmadov, F.; Ahmed, W. S.; Ahuja, S.; Ai, X.; Aielli, G.; Aikot, A.; Ait Tamlihat, M.; Aitbenchikh, B.; Aizenberg, I.; Akbiyik, M.; Åkesson, T. P. A.; Akimov, A. V.; Akiyama, D.; Akolkar, N. N.; Aktas, S.

A search for a new heavy boson produced via gluon-fusion in the four-lepton channel with missing transverse momentum or jets is performed. The search uses proton-proton collision data equivalent to an integrated luminosity of 139 fb⁻¹ at a centre-of-mass energy of 13 TeV collected by the ATLAS detector between 2015 and 2018 at the Large Hadron Collider.

This study explores the decays of heavy bosons: 𝑅 → 𝑆𝐻 and 𝐴 → 𝑍𝐻, where 𝑅 is a CP-even boson, 𝐴 is a 𝐶𝑃-odd boson, 𝐻 is a 𝐶𝑃-even boson, and 𝑆 is considered to decay into invisible particles that are candidates for dark matter.

In these processes, 𝑆 → invisible and 𝐻 → 𝑍𝑍. The 𝑍 boson associated with the heavy scalar boson 𝐻 decays into all decay channels of the 𝑍 boson. The mass range under consideration is 390–1300 (320–1300) GeV for the 𝑅 (𝐴) boson and 220–1000 GeV for the 𝐻 boson. No significant deviation from the Standard Model backgrounds is observed. The results are interpreted as upper limits at a 95% confidence level on the cross-section times the branching ratio of the heavy resonances.