# Jet Identification with Zest

## TL;DR

This paper introduces a new jet observable called zest that effectively distinguishes between different types of particle jets, such as gluons, top quarks, and vector bosons, with properties like boost invariance and stability.

## Contribution

The paper proposes zest, a novel observable for jet identification, demonstrating its robustness and effectiveness in differentiating jet origins, especially when combined with other observables.

## Key findings

- Zest is boost invariant and stable against soft particle variations.
- Zest effectively differentiates gluon jets from others.
- Using zest improves gluon rejection while maintaining high signal efficiency.

## Abstract

We present a new observable zest and demonstrate its potential to differentiate between jets originated by gluons, top quark and vector bosons. Zest has salient properties such as boost invariance, stability against global color flow of partons and inclusion or exclusion of a few soft particles to the jet. For a gluon jet, zest distribution is also insensitive to the jet mass. We show that when zest is used in conjunction with other observables, it can yield high gluon rejection while retaining high signal sample.