Search for isolated photons from flavor-changing neutral-current decay of a new quark at the KEK <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span><span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>e</mi></mrow><mrow><mi mathvariant="normal">−</mi></mrow></msup></mrow></math></span> collider TRISTAN

doi:10.1103/PhysRevLett.63.1776

Search for isolated photons from flavor-changing neutral-current decay of a new quark at the KEK $e^{+}$ $e^{-}$ collider TRISTAN

K. Abe et al.

Phys. Rev. Lett. 63, 1776 – Published 23 October 1989

Abstract

A search for a new charge -(1/3 quark has been carried out at the KEK $e^{+}$ $e^{-}$ Collider TRISTAN under the assumption of its photonic decay through a flavor-changing neutral current (FCNC). The observed number of multihadronic events with isolated photons is consistent with that expected from the known five quark flavors. Including the usual charged-current decays, limits on the absolute photonic branching ratio and FCNC processes were obtained.