Apparent Excess in e+e- --> hadrons

Abstract

We have studied measurements of the cross section for e+e- --> hadrons for center-of-mass energies in the range 20--209 GeV. We find an apparent excess over the predictions of the Standard Model across the whole range amounting to more than 4σ. As an example, we compare the data to predictions for a light scalar down-type quark which fit the excess well.

Latex. 22 pages, 8 figures