Associated production of graviton with $e^+e^-$ pair via photon-photon collisions at a linear collider

TL;DR

This paper studies the production of Kaluza-Klein gravitons in photon-photon collisions at a future linear collider, demonstrating potential detection of extra dimensions with specific energy and polarization configurations.

Contribution

It provides the first detailed analysis of graviton production via photon-photon collisions at the ILC, including polarization effects and detection strategies for extra dimensions.

Findings

Cross section can reach hundreds of fb at 00-1000 GeV energies.

Polarized photon collisions significantly enhance detection prospects.

Detection limits for extra dimensions are established for various collider configurations.

Abstract

We investigate the process \rreeG at the future International Linear Collider(ILC), where G_n is the Kaluza-Klein graviton in the Large Extra Dimension Model. When the fundamental energy scale is of a few ${\rm TeV}$, the cross section of this process can reach several hundred fb at a photon-photon collider with $\sqrt{s}=500 \sim 1000 GeV$, and the cross section in J=2 polarized photon collision mode is much larger than that in J=0 polarized photon collision mode. We present strategies to distinguish the graviton signal from numerous SM backgrounds, and find that the graviton signal with extra dimensions $\delta=3$ can be detected when ${\rm M_S} \le 2.67(1.40) {\rm TeV}$ and $\gamma \gamma$ c.m.s. energy $\sqrt{s}=1000(500) {\rm GeV}$ in unpolarized photon collision mode, while the detecting upper limit can be increased to 2.79(1.44) ${\rm TeV}$ in $+ -$ ($\lambda_1=1$, $\lambda_2=-1$) polarized photon collision mode(with photon polarization efficiency $P_{\gamma}=0.9$).