Portals to New Physics: The W-Quark Portal

TL;DR

This work develops a comprehensive effective field theory framework—the W-quark portal—for Beyond the Standard Model physics, cataloging all possible interactions up to dimension $6$ that couple a single light exotic (LEX) state to SM fields via at least one quark and one $W$ boson. A structured operator basis is built for both scalar and fermionic LEX fields, including derivatives and field-strength couplings, with careful attention to redundancy via integration by parts and equations of motion. The authors analyze collider phenomenology across $pp$ and $ep$ colliders, identifying a rich set of production and decay topologies, including high-representation SU(3) and SU(2) states such as triplets, sextets, octets, quadruplets, and quintuplets, and they provide a concrete LHC study of a fermionic SU(3) triplet quadruplet to illustrate cross sections and kinematic features. The framework offers a maximally general catalog intended to guide experimental searches and motivate UV-complete constructions, precision tests, and further EFT explorations of exotic states reachable through the W-quark portal.

Abstract

We explore new EFT operators where single new exotic states interact with the Standard Model through an asymmetric Standard Model portal with couplings to at least one quark and one W boson. Effective operators up to dimension 6 are considered, and we specify SM charges of all new states accessible through this portal. We explore our interactions by detailing possible collider production processes at e-p and p-p colliders. Finally, we study the LHC production of a new weak-quadruplet SU(3) fundamental fermion which can be singly produced in association with a SM quark through W-quark portal processes.