Search for Large Extra Dimensions Using Dielectron and Diphoton Events in $p\bar{p}$ Collisions at $\sqrt{s}=1.8$ TeV

TL;DR

This paper searches for evidence of large extra dimensions by analyzing dielectron and diphoton events in proton-antiproton collisions, setting limits on the fundamental Planck scale in the context of the ADD model.

Contribution

First experimental search for large extra dimensions using dielectron and diphoton data at Fermilab, establishing new limits on the Planck scale $M_S$.

Findings

No significant excess observed in data

95% CL limits on $M_S$ of 905 GeV/$c^2$ and 826 GeV/$c^2$

Constraints on models with large extra dimensions

Abstract

Arkani-Hamed, Dimopoulous, and Dvali have proposed a model of low-scale quantum gravity featuring large extra dimensions. In this model, the exchange of Kaluza-Klein towers of gravitons can enhance the production rate of electron and photon pairs at high invariant mass in proton-antiproton collisions. The amount of enhancement is characterized by the parameter $M_S$, the fundamental Planck scale in the bulk extra dimensions. We have searched for this effect using 100 pb$^{-1}$ of diphoton data and 110 pb$^{-1}$ of dielectron data collected with the Collider Detector at Fermilab at $\sqrt{s}=1.8$ TeV during the 1992-1996 run. In the absence of a signal, we place 95% confidence-level limits on $M_S$ of 905 GeV/$c^2$ and 826 GeV/$c^2$, for the case of constructive and destructive graviton interference respectively.