A Miniature Spectrometer for a Hybrid Emulsion Experiment to Measure B-Particle Lifetimes
Nuclear emulsion is the only proven technique having position resolution ≲ 1µ, and therefore capable of relatively bias-free measurement of lifetimes down to ~ 10-15 sec for decaying particles with γ ~ 25. Hybrid experiments using spectrometers1–4 and bubble chambers5,6 to tag the location of events in emulsion have provided the first measurements of charmed particle lifetimes. These experiments have exploited the relatively large yield of charm in neutrino (~ 5%) and photon (~ 1%) interactions by searching the emulsion for every tagged event. Measuring the lifetimes of particles carrying the beauty quantum number will be much more difficult because of the tiny yield expected at energies available now or in the near future: ≲ 10-4 in neutrino beams, and ~ 1/500 of charm in photon and hadron beams’. Nevertheless, the hybrid emulsion technique can indeed provide the first measurements of B-particle lifetimes if hadronic production of BB̄ pairs has a cross section ≳ 10 nanobn, well within current estimates.
KeywordsSilicon Detector Drift Chamber Neutrino Beam Hybrid Emulsion Downstream Drift
Unable to display preview. Download preview PDF.
- 1.E.H.S. Burhop et al., Phys. Lett. 65B: 299 (1976).Google Scholar
- 2.M. I. Adamovich et al., Phys. Lett. 89B: 427 (1980).Google Scholar
- 5.C. Angelini et al., Phys. Lett. 84B: 150 (1979).Google Scholar
- 6.R. Ammar et al., Phys. Lett. 94B: 118 (1980).Google Scholar
- 7.See, e.g., J. Leveille in “Proceedings of the 1980 Tevatron Workshop”, to be published.Google Scholar
- 8.N. Ushida et al., Fermilab Proposal 653 (1980).Google Scholar
- 9.S. R. Amendolia et al., A Multielectrode Silicon Detector for High Energy Physics Experiments, PISA 80–2 (1980).Google Scholar
- 10.E.H.M. Heijne et al., A Silicon Surface Barrier Microstrip Detector Designed for High Energy Physics, CERN/EF/BEAM 80–6 (1980).Google Scholar
- 11.G. Baroni, Report on CERN NA-19 at 1980 Tevatron Workshop.Google Scholar