Searching for ALP Lepton Flavor Violation via ALP Decays at the LHC

Abstract

In the ALP model, lepton flavor violation (LFV) can arise from off-diagonal ALP-lepton couplings ($g_{a{\ell }_i{\ell }_j}$), which are absent in the Standard Model. We focus on ALP production via gluon fusion ($pp\to a$) at the Large Hadron Collider (LHC), which dominates the ALP mass range of 5-1000 GeV due to its high cross section and manageable backgrounds. We are interested in the decay of an axion into an electron and a muon, two oppositely charged leptons of different flavors. After background suppression, we obtain the sensitivity to ALP in this mass range, finding significantly improved limits for $5<m_a<1000$ GeV, where SM backgrounds are suppressed. Our research is complementary with relevant studies.

Comments: Formatting errors were found in the manuscript after submission. Specifically, there are issues with the display of mathematical symbols and incorrect unit notations in figures and tables throughout the document, which affect readability. We are withdrawing this version to correct these technical formatting issues and will submit a properly formatted replacement version