The decay modes $F\left(c\overline{s}\right)$,$B(b\overline{u},b\overline{c})\to \tau \nu$ are proposed as triggers for $e^{+}{e}^{-}\to F\overline{F}$,$B\overline{B}$ production. Decay branching fractions of order $B\left(F\right)\mathrm{}\simeq 15\%$ and $B\left(B\right)\mathrm{}\simeq \left(1\mathrm{} \mathrm{to} 2\right)\%$ are estimated. The sequential $\tau \to e\nu \overline{\nu }$,$\mu \nu \overline{\nu }$ decays provide clear signatures, with the hadronic decay of the associated $F$, $B$ carrying exactly half the energy. These triggers can be extended to study $F^{*}$ and $B^{*}$ resonance production and also to exploit the $\tau \to \pi \nu$,$\rho \nu$,$A_1\nu$ decays.

• Received 19 February 1980

DOI:https://doi.org/10.1103/PhysRevLett.45.83