Tagging a mono-top signature in Natural SUSY

TL;DR

This paper explores a novel mono-top signature in Natural SUSY to detect light stops and higgsinos, demonstrating that the hadronic channel significantly improves detection sensitivity at the LHC.

Contribution

It introduces a new mono-top channel via $pp o t ilde t_1 ilde chi^0_{1(2)}$ process, enhancing detection prospects for compressed SUSY spectra.

Findings

Hadronic mono-top channel improves background discrimination.

Sensitivity reaches up to 420 GeV for stop mass at 13 TeV LHC.

Significant enhancement over leptonic channel detection capabilities.

Abstract

We study the feasibility of probing a region of Natural Supersymmetry where the stop and higgsino masses are compressed. Although this region is most effectively searched for in the mono-jet channel, this signature is present in many other non-supersymmetric frameworks. Therefore, another channel that carries orthogonal information is required to confirm the existence of the light stop and higgsinos. We show that a supersymmetric version of the $t \bar t H$ process, $pp \to t \tilde t_1 \tilde \chi^0_{1(2)}$, can have observably large rate when both the stop and higgsinos are significantly light, and it leads to a distinctive mono-top signature in the compressed mass region. We demonstrate that the hadronic channel of the mono-top signature can effectively discriminate the signal from backgrounds by tagging a hadronic top-jet. We show that the hadronic channel of mono-top signature offers a significant improvement over the leptonic channel and the sensitivity reaches $m_{\tilde t_1} \simeq 420$ GeV at the 13 TeV LHC with 3 ab$^{-1}$ luminosity.