Leptonic CP-violation in the sneutrino sector of the BLSSM with Inverse Seesaw

TL;DR

This paper investigates CP violation in the sneutrino sector of the BLSSM with inverse seesaw, proposing a novel analysis method using boosted decision trees at future colliders to detect CP-violating effects.

Contribution

It introduces a new approach combining T-odd observables and machine learning techniques to identify CP violation in sneutrino decays at high-energy colliders.

Findings

CP violation induces measurable asymmetries in T-odd observables.

Boosted decision trees improve sensitivity to CP-violating signals.

A Z' boson near current bounds enhances sneutrino production.

Abstract

We study CP violation (CPV) in the sneutrino sector within the B-L extension of the Minimal Supersymmetric Standard Model (BLSSM), wherein an inverse seesaw mechanism has been implemented. CPV arises from the new superpotential couplings in the (s)neutrino sector, which can be complex and the mixing of CP-eigenstates induced by those couplings. CPV leads to asymmetries in so called T-odd observables, but we argue that such asymmetries also lead to a wider distribution of those observables. We look at a final state where a sneutrino decays to a lepton, two jets and missing transverse momentum at the Future Circular Collider operating in hadron-hadron mode at $100$ TeV and with a luminosity of 3 ab$^{-1}$. In order to exclude the CP conserving scenario we need to improve traditional analysis by introducing boosted decision trees using both standard kinematic variables and T-odd observables and we need $Z^{\prime}$ boson not too much above current bounds as a portal to produce sneutrinos efficiently.