Abstract
In superstring theories, there are new fermion fields which lie in the 27-dimensional representation along with the known fermions. We examine possible production modes of these exotic fermions and their likely decays. Whereas collider data exclude new charged fermions with masses below 23 GeV, it appears that present pp¯ collider data for dimuons and for isolated single electrons exclude exotic quarks with masses below 30 GeV and considerable regions of lepton mass assignments in the range 20–45 GeV (assuming &). We place constraints on the mixings of the exotic fermions from experimental limits on flavor-changing neutral currents and the observed weak universality of charged-current interactions. The decays of the exotic h quark (singlet, charge -(1/3)) satisfy the bound Γ(h→)/Γ(h→ueν)≳12%. Production and decays of very heavy exotics are also considered.
- Received 4 December 1985
DOI:https://doi.org/10.1103/PhysRevD.33.1912
©1986 American Physical Society