POSSIBILITY TO STUDY THE PRODUCTION AND DECAY SYSTEMATICS OF SHORT-LIVED (TAU-GREATER-THAN-OR-EQUAL-TO-10-S-13) NEW PARTICLES IN HADRONIC REACTIONS USING THE BUBBLE-CHAMBER TECHNIQUE

We consider the application of the bubble chamber technique to the detection and study of charmed particles (or other short-lived particles) produced in hadronic interactions. We conclude that a spectrometer containing as its target a small rapid cycling bubble chamber with spatial resolution of ∼ 10 μm could provide a valuable means of studying particles with lifetime τ ≳ 10-13 s, giving a well-resolved view of the production and decay vertices for a large proportion of the events. Development of a system with the necessary optical resolution, as well as providing an experimental sensitivity of up to ∼ 100 events/μb · d, appears within the range of technical feasibility. As a further result of our calculations, we find that the recently quoted upper limitfor production of charmed particles in emulsion by 300 GeV/c protons, σ < 1.5 μb (90% C.L.) is only correct for τ {reversed tilde equals} 10-14 s. For longer lifetimes the upper limit should be understood as a function of lifetime, varying between the quoted ∼ 1.5 μb for τ ∼ 10-14 s to ∼ 40 μb for τ ∼ 10-12 s. If the inclusive cross sections are in the tens of microbarns range, with the lifetime τ ∼ 10-2 s, then it should be possible to detect charmed particle tracks using chambers such as the RCBC of the European Hybrid Spectrometer (E.H.S.) and the 30″ chamber at FNAL. © 1979 North-Holland Publishing Co.