Prominent decay modes of a leptophobic Z′

Abstract

An anomaly-free U(1) charge $Q'$ has recently been identified within the\ngroup E$_6$ for which the familiar leptons (the left- and right-handed electron\nand the left-handed neutrino) have $Q' = 0$. It is pointed out that the $Q'$\ncharges of several {\\it exotic} leptons within E$_6$ matter multiplets are\nquite large, leading to the prediction that half of the decays of the so-called\n``leptophobic'' $Z'$ bosons coupling to $Q'$ are to these exotic leptons. Other\nlarge $Q'$ charges include those of standard up-type quarks and exotic\ndown-type quarks. Substantial forward-backward asymmetries are expected in $u\n\\bar u \\to Z' \\to f \\bar f$ channels when $f$ is a standard up-type quark, an\nexotic down-type quark, or an exotic lepton.\n