Search for Top Squarks at Tevatron Inspired by Dark Matter and Electroweak Baryogenesis

TL;DR

This paper proposes a novel search strategy for top squarks at Tevatron, motivated by their potential role in dark matter and baryogenesis, focusing on a distinctive $2j + \not E_T$ signature with an isolated energy cluster.

Contribution

It introduces a new detection method based on decay length signatures for top squarks in a mass range relevant to dark matter and baryogenesis, enhancing search sensitivity.

Findings

Preliminary simulations suggest detectability for $100-130$ GeV/c^2 top squark masses.

The proposed strategy could reveal signals even when traditional methods fail.

Potential to observe hints of new physics at higher top squark masses.

Abstract

The search for the top squark ($\widetilde{t}_{1}$) within the kinematic reach of Tevatron Run II is of great contemporary interest. Such a $\widetilde{t}_{1}$ can explain the baryon asymmetry of the universe provided $120 ~GeV/c^{2} \leq m_{\widetilde{t}_{1}} \leq m_t$. Moreover if $\Delta m \equiv m_{\widetilde{t}_{1}}$ - $m_{\widetilde\chi_1^0}$ is small, where $\widetilde\chi_1^0$ is the LSP, the dark matter relic density as obtained from the WMAP data may be explained via $\widetilde{t}_{1}$- LSP coannihilation. In this scenario the decay $\widetilde{t}_{1} \to c \widetilde\chi_1^0$ is likely to occur with 100 % branching ratio but for small $\Delta m$ the conventional di-jet + $\not E_T$ signal becomes unobservable. We propose a new search strategy based on the $2j + \not E_T$ signature accompanied by an isolated cluster of energy which arises from a decaying heavy particle with characteristic decay length. Our preliminary simulations with PYTHIA indicate that for $100 ~GeV/c^{2} \le m_{\widetilde{t}_{1}} \le 130 ~GeV/c^{2}$ this signal may be observable while somewhat lager $m_{\widetilde{t}_{1}}$ may still provide hints of new physics.