A search for T-violating transverse muon polarization (PT ) in the K + → π 0 µ + ν decay was performed using kaon decays at rest. A new improved value, PT = −0.0017 ± 0.0023(stat) ± 0.0011(syst), was obtained giving an upper limit, |PT | < 0.0050. The T-violation parameter was determined to be Imξ = −0.0053 ± 0.0071(stat) ± 0.0036(syst) giving an upper limit, |Imξ| < 0.016. PACS numbers: 11.30.Er, 12.60.Fr, 13.20.Eb The transverse muon polarization, P T , in the) decay is one of the observables of CP violation beyond the standard model (SM). CP violation in general is a subject of continuing interest in K and B meson decays. P T , defined as the polarization component perpendicular to the decay plane, is an obvious signature of a violation of time reversal (T) invariance, since the spurious effect from final state interactions is very small (< 10 −5 ) [1]. P T is almost vanishing (∼ 10 −7 ) in the SM with the Kobayashi-Maskawa scheme [2]; it is therefore a very sensitive probe of CP violation mechanisms beyond the SM and new physics along with B physics such as b → sγ and some other decays [3]. Models [4] such as those with multi-Higgs doublets or leptoquarks, or some SUSY may to give rise to P T as large as 10 −3 .At the High Energy Accelerator Research Organization (KEK) the E246 collaboration has been performing a search for P T in K + µ3 . In 1999, the first result was published [5] based on ∼ 3.9 × 10 6 good K + µ3 events from the data taken during 1996 and 1997, indicating no evidence for T violation. Further runs provided a cumulative data sample with three times more events. This Letter constitutes our final result from all the data with an improved analysis. The present result supersedes all our earlier reports.
The reaction between dithiomalondianilide (N,N’-diphenyldithiomalondiamide) and alkyl 3-aryl-2-cyanoacrylates in the presence of morpholine in the air atmosphere leads to the formation of alkyl 6-amino-4-aryl-7-phenyl-3-(phenylimino)-4,7-dihydro-3H-[1,2]dithiolo[3,4-b]- pyridine-5-carboxylates in 37–72% yields. The same compounds were prepared in 23–65% yields by ternary condensation of aromatic aldehydes, ethyl(methyl) cyanoacetate and dithiomalondianilide. The reaction mechanism is discussed. The structure of ethyl 6-amino-4-(4-methoxyphenyl)-7-phenyl-3-(phenylimino)-4,7-dihydro-3H-[1,2]dithiolo[3,4-b]pyridine-5-carboxylate was confirmed by X-ray crystallography. Two of the prepared compounds showed a moderate growth-stimulating effect on sunflower seedlings. Three of the new compounds were recognized as strong herbicide safeners with respect to herbicide 2,4-D in the laboratory and field experiments on sunflower.
Microlens arrays for Shack-Hartmann wavefront sensors were fabricated by field-assisted silver ion migration in glass. The theoretical model was made, which describes the dependence of the parameters of microlenses in matrix on technological process of lens fabrication. The technological regimes are selected, allowing to make microlens arrays with wide range of optical parameters for measuring various wavefront distortions.
The ratio of the K + → π 0 µ + ν (K + µ3 ) and K + → π 0 e + ν (K + e3 ) decay widths, Γ(K µ3 )/Γ(K e3 ), has been measured with stopped positive kaons. K + µ3 and K + e3 samples containing 2.4×10 4 and 4.0×10 4 events, respectively, were analyzed. The Γ(K µ3 )/Γ(K e3 ) ratio was obtained to be 0.671±0.007(stat.)±0.008(syst.) calculating the detector acceptance by a Monte Carlo simulation. The coefficient of the q 2 dependent term of the f 0 form factor was also determined to be λ 0 =0.019±0.005(stat.)±0.004(syst.) with the assumption of µ-e universality in K + l3 decay. The agreement of our result with the λ 0 value obtained from K + µ3 Dalitz plot analyses supports the validity of the µ-e universality.
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