Using the ARGUS detector at the
e
+
e
− storage ring DORIS II, we have determined the Michel parameters ξ and δ of
τ
∓ → l
∓ν
ν
-
decays. With an integrated luminosity of 445 pb
−1 around
s
= 10
GeV, ...we have produced approximately 415000 τ-pairs. From this data sample, 3262 events were selected with
e
+e
− → τ
+τ
− → (l
±ν
ν
-
) (π
∓π
+π
−ν)
. The semihadronic decay was used as analyser of the τ-spin and made possible - owing to the spin correlations - the determination of the parity-violating Michel parameters ξ and δ in the decay
τ
∓ → l
∓ν
ν
-
. Simultaneously to the determination of the Michel parameters, a measurement of the τ-neutrino helicity
h
ν
τ
in the decay
τ
∓ →
π
∓
π
+
π
−
ν was obtained. We observed
h
ν
τ
= −0.85
−0.17
+0.15 ± 0.05,
ϱ = 0.721 ± 0.040 ± 0.021,
ξ = 1.26
−0.26
+0.30 ± 0.09, and
ξδ = 0.77
−0.16
+0.18 ± 0.05. In addition, the combined ARGUS result on
h
ν
τ
, ϱ, ξ, and ξδ are reported using this work and previous measurements.
Using the ARGUS detector at the
e
+
e
− storage ring DORIS II at DESY, we have studied lepton energy spectra in τ decays. We present a “pseudo-rest-frame” technique in which the second τ in the ...event, decaying into a heavy hadronic system, is used as reference. This method allows for the first measurement of the Michel Parameter η in τ decays. We also determine the Michel Parameter ρ in τ →
ev̄v decays with a precision comparable to the present world average. The measured values of the parameters ρ=0.735±0.036±0.020 and η=0.03±0.18±0.12 are in good agreement with standard V-A coupling at the τ-ν-W vertex.
Using the ARGUS detector at the
e
+
e
− storage ring DORIS II at DESY, we have made two measurements of the mixing parameter
χ
d
using kaons as flavour tags. Using
D
∗+ K
±
correlations we found
χ
d
...= 0.20 ± 0.13 ± 0.12 and from the study of
(D
∗+ℓ
−) K
±
correlations we obtained
χ
d
= 0.19 ± 0.07 ± 0.09. The branching ratio for
B → D
∗+ X
has been updated:
Br(
B → D
∗+ X) = (19.6 ± 1.9)
%. We have also determined the average multiplicity of charged kaons in
B
0 decays to be 0.78 ± 0.08.
The seasonal differences of transport and deposition of atmospheric lead over the coastal zone of northern Germany are investigated. It is shown that marked differences can occur in the effect on the ...ecologically valuable Wadden Sea areas. Because of the formation of sea-breeze systems in summer, the coastal zone is likely to be less stressed despite the partial trapping of the pollutant in the sea-breeze cell than it is in winter when the pollutant is confined to a shallow layer above ground. The flow and concentration pattern in the summer are sensitive to the proper incorporation of clouds (if there are any). An exact modeling of the temporal emission pattern is found to be of minor importance.
Ferroelectric liquid crystalline (LC) polymers, which in the smetic C* phase exhibit the highest yet known spontaneous polarization for LC polymers of up to 430 nC/cm exp 2 , a value which approaches ...that of the best low molecular weight materials, have been synthesized, based on chiral polysiloxanes. A copolymer is also reported which shows promise for second harmonic generation (frequency doubling) of the 1064 nm Nd:YAG fundamental (to 532 nm) without poling in an external field.
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