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An irrigation experiment with saline water at different concentrations was carried out over a 7-year period on the same clay–silty soil in the Volturno Valley at Vitulazio to evaluate long-term effects of irrigation with saline water on crops and soil. The spatial distribution of the experimental treatments remained the same throughout the 7-year period in order to assess the effects of salt accumulation. Three saline concentrations of irrigation water (0.25–0.5 and 1% of NaCl) and two irrigation levels (100% and 40% restitution of evapotranspiration) were applied. The electrolytic concentration (ECe) was measured every year in spring before the irrigation season. Autumn–spring rainfall caused leaching of salts from 0 to 0.4 m layer and an accumulation of salt in the deeper layers. Accumulation was directly correlated to the quantity of NaCl applied with irrigation. This allowed us to calculate, for the 0.4–1.1 m layer, the mean annual increase in ECe in (dS m −1 per t ha −1 year −1 of NaCl given). At the end of the experiment, it was observed that there was an increase in ECe at a depth of 3 m for the saltiest treatments. The percentage of exchangeable sodium (ESP), however, increased with the saline concentration of the irrigation water (quantity of NaCl) above all in the 0–0.4 m layer, and gradually decreased with depth. Irrigation with saline water led to an increase in ESP and a degradation of the soil physical properties that were estimated indirectly by measuring aggregate stability in water (IASW). The index of aggregate stability in water for the top layer (0–0.15 m) was inversely correlated to the ESP values, even after the leaching due to the autumn–spring rainfall.

A technipion and an elementary Higgs particle with a mass greater than about 10 GeV can always be distinguished by a 10–20% accuracy measurement of the full sequential decay correlation function I(E1, E2, cos ψ12) = S + γCPD in the Higgs/technipion rest frame for a decay mode such as τ τ with τ ± → l ± ν ν or t t with t → bμ+ν, t → b μ − ν , where E1,2 are the charged lepton energies and ψ12 is the angle between the charged lepton momenta. For the charged leptons back-to-back, in the extreme relativistic scaling limit D/S ≅ 21% for E1 = E2 ≅ (Emax/2), whereas for MH = 70 GeV already D/S ≅ 19% so the scaling limit is rapidly reached. If for the t t mode the b jets′ momenta are also measured, then a correlation function in t quark rest frames′ helicity angles and energies can be used instead to determine γCP but from a much smaller number of events. This procedure is possible because the standard ν ν correlation function is symmetric in the azimuthal angle φ ν ν , so cos φ ν ν and the helicity polar angles θν and θ ν of the missing and antineutrino are measurable in spite of a two-fold kinematic ambiguity in the t and t momenta directions. If the top quark has a mass mt ≥ 100 GeV, the t t mode with t → bW+, t → b W − can be used to determine γCP by measuring the two b jets′ momenta.

For spin- 0 decay into τ+τ− yielding an observable lepton pair l1l2 from τ ± → l ± ν ν , the full sequential decay correlation function I(E1, E2, cos ψ12) = S + γCPD in the Higgs/technipion rest frame is obtained analytically for massless final leptons where ψ12 is the angle between the l1 and l2 momenta. For fixed ψ12, contour plots of this decay correlation function for MH = 9 GeV show that there is about a 10% difference between γCP = ±. In the near non-relativistic limit where MH ≅ 2mτ the γCP signature is a much larger effect, |D/S| is roughly ∼ 50%. In contrast, the energy correlation function I(E1, E2) does not depend on γCP.