https://doi.org/10.1140/epjc/s10052-020-8210-5
Regular Article - Theoretical Physics
Lepton flavor violation and dilepton tails at the LHC
1
Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
2
Physik-Institut, Universität Zürich, 8057, Zürich, Switzerland
3
Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova, Padua, Italy
4
Istituto Nazionale Fisica Nucleare, Sezione di Padova, 35131, Padua, Italy
* e-mail: aangelescu2@unl.edu
Received:
16
March
2020
Accepted:
7
July
2020
Published online:
19
July
2020
Starting from a general effective Lagrangian for lepton flavor violation (LFV) in quark-lepton transitions, we derive constraints on the effective coefficients from the high-mass tails of the dilepton processes 
(with 
). The current (projected) limits derived in this paper from LHC data with 
(
) can be applied to generic new physics scenarios, including the ones with scalar, vector and tensor effective operators. For purely left-handed operators, we explicitly compare these LHC constraints with the ones derived from flavor-physics observables, illustrating the complementarity of these different probes. While flavor physics is typically more constraining for quark-flavor violating operators, we find that LHC provides the most stringent limits on several flavor-conserving ones. Furthermore, we show that dilepton tails offer the best probes for charm-quark transitions at current luminosities and that they provide competitive limits for tauonic 
transitions at the high-luminosity LHC phase. As a by-product, we also provide general numerical expressions for several low-energy LFV processes, such as the semi-leptonic decays 
, 
and 
.
© The Author(s), 2020
