Related Experiment Video
Updated: May 27, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Quark and gluon tagging at the LHC
Jason Gallicchio1, Matthew D Schwartz
1Department of Physics, Harvard University , Cambridge, Massachusetts 02138, USA.
Abstract:
Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing and novel jet substructure observables, we find that a multivariate approach can filter out over 95% of the gluon jets while keeping more than half of the light-quark jets. Moreover, a combination of two simple variables, the charge track multiplicity and the p(T)-weighted linear radial moment (girth), can achieve similar results. Our study is only Monte Carlo based, so other observables constructed using different jet sizes and parameters are used to highlight areas that deserve further theoretical and experimental scrutiny. Additional information, including distributions of around 10,000 variables, can be found at http://jets.physics.harvard.edu/qvg/.
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