A search for quarks at the CERN intersecting storage rings

No quark candidates have been seen among 0.6 × 10⁹ charged particles at the ISR. The corresponding cross-section limit for charge for quark masses up to 22(13) GeV, assuming P_T = 0.4 GeV/c.     

Neighboring hydrogen, isotope effect, and conformation in solvolysis of 3-methyl-2-butyl p-toluenesulfonate

In connection with hydrogen participation in solvolysis, 3-methyl-2-butyl p-toluenesulfonate is a marginal system. Comparison of the behavior of 3-D-3-methyl-2-butyl toluenesulfonate with that of the undeuterated analog discloses a substantial isotope effect on solvolysis rate, but only a small effect on product composition. The evidence points to a relatively high value of (k_Δ/k_s), the ratio of rate constants for anchimerically assited and unassisted solvolysis processes. Conformational considerations make understandable the relatively low degree of rate acceleration displayed by 3-methyl-2-butyl toluenesulfonate.     

A limit on the lepton-family number violating process π → μe

A FNAL E799 Collaboration has carried out a search for the lepton-family number violating decay π⁰ → μ^±e using π⁰'s produced from K_L → π⁰π⁰π⁰ decays in flight. No events were observed. Assuming that lepton-family number violation is charge independent, the 90% confidence level upper limit on

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was determined to be 8.6 × 10⁻⁹.     

Search for lepton-flavor-violating decays of the neutral kaon

The Fermilab KTeV experiment has searched for lepton-flavor-violating decays of the K(L) meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their branching ratios at the 90% C.L.: BR(K(L) --> pi(0) micro(+/-) e(-/+)) <7.6 x 10(-11); BR(K(L) --> pi(0)pi(0) micro(+/-) e(-/+)) <1.7 x 10(-10); BR(pi(0) --> micro(+/-) e(-/+)) <3.6 x 10(-10). This result represents a factor of 82 improvement in the branching ratio limit for K(L) --> pi(0) micro(+/-) e(-/+) and is the first reported limit for K(L) --> pi(0)pi(0) micro(+/-) e(-/+).