The implications of final L3 measurement of $σ_{tot}(γγ\to b\bar{b}

Abstract

he excess of data on the total cross section of $\bar{b}b$ production in $γγ$ collisions over QCD predictions, observed by L3, OPAL and DELPHI Collaborations at LEP2, has so far defied explanation. The recent final analysis of L3 data has brought important new information concerning the dependence of the observed excess on the $γγ$ collisions energy $W_{γγ}$. The implications of this dependence are discussed.