Unparticle physics at the photon collider

TL;DR

This paper explores how unparticle physics, a novel concept beyond the Standard Model involving a hidden conformal sector, can significantly affect photon-photon scattering at colliders, potentially revealing properties of unparticles through precise measurements.

Contribution

It investigates the impact of unparticles on gamma gamma to gamma gamma scattering at photon colliders, highlighting potential observable deviations from the Standard Model predictions.

Findings

Unparticle effects cause sizable deviations in gamma gamma scattering.

The cross section depends on the unparticle scaling dimension d_U.

Precision measurements can reveal the unparticle's scaling dimension.

Abstract

Recently, a conceptually new physics beyond the Standard Model (SM), unparticle, has been proposed, where a hidden conformal sector is coupled to the SM sector through higher dimensional operators. In this setup, we investigate unparticle physics at the photon collider, in particular, unparticle effects on the gamma gamma to gamma gamma process. Since this process occurs at loop level in the SM, the unparticle effects can be significant even if the cutoff scale is very high. In fact, we find that the unparticle effects cause sizable deviations from the SM results. The scaling dimension of the unparticle d_U reflects the dependence of the cross section on the final state photon invariant mass, so that precision measurements of this dependence may reveal the scaling dimension of the unparticle.