Illuminating New Electroweak States at Hadron Colliders

TL;DR

This paper introduces a new search strategy at hadron colliders for detecting uncolored electroweak states, especially when they are nearly degenerate and produce missing energy signatures.

Contribution

It proposes using photon radiation from charged states to distinguish signals of new electroweak particles from Standard Model backgrounds, applicable to various models.

Findings

Effective discrimination of signals using photon radiation technique.

Application demonstrated on Higgsino doublet and electroweak quintuplet.

Broad applicability to searches for new electroweak states.

Abstract

In this paper, we propose a novel powerful strategy to perform searches for new electroweak states. Uncolored electroweak states appear in generic extensions of the Standard Model (SM) and yet are challenging to discover at hadron colliders. This problem is particularly acute when the lightest state in the electroweak multiplet is neutral and all multiplet components are approximately degenerate. In this scenario, production of the charged fields of the multiplet is followed by decay into nearly invisible states; if this decay occurs promptly, the only way to infer the presence of the reaction is through its missing energy signature. Our proposal relies on emission of photon radiation from the new charged states as a means of discriminating the signal from SM backgrounds. We demonstrate its broad applicability by studying two examples: a pure Higgsino doublet and an electroweak quintuplet field.