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[en] Green Field II (GFII) project conducted in Israel during 2010-11 aimed at increasing the preparedness for possible terrorism events, where a radioactive material coupled to an explosive charge might be dispersed. The project included seven tests where ∼6Ci of 99mTc was dispersed by 0.25-2.5 kg TNT charges. The dispersion was done above clean or dirt surfaces, from the ground level or 1m above it. Comparison between the different situations will be shown as well as new parameterizations suggested to being included within the existing models. The paper will describe the project objectives, the experimental setups, some of the results obtained in these experiments and preliminary analysis of these results
[en] Complete text of publication follows. Field-line eigen-oscillations caused by the field line resonance (FLR), observed in the ground magnetometer data, are useful for us to estimate the magnetospheric plasma mass density from the ground, because the eigen-frequency (FLR frequency below) decreases with increasing plasma mass along the field line. However, FLR frequencies are often difficult to identify in the ground magnetometer data, because different kinds of waves with large amplitudes are often superposed onto the FLR signal and mask the FLR signal. As countermeasures to this problem, methods called amplitude-ratio method and cross-phase method have been used; these methods take the difference between the data from two magnetometers that are latitudinally separated by an order of 100km. However, a problem here is that the two methods can yield different values of the FLR frequency from the same dataset. Hodograph method [Pilipenko and Kurchashov, 2000] is a solution to this problem, because it merges the amplitude-ratio method and the cross-phase method into one method. It can also estimate the resonance width. However, the resonance width is assumed to be a constant of latitude in the hodograph method, while in reality the resonance width can be a function of latitude. In this paper we have improved the hodograph method to solve this problem. That is, we have introduced a latitude dependence of the resonance width into the hodograph method. We have tested this improved method by simulated datasets and observed datasets, and the results are successful.
[en] Neutral ytterbium atoms embedded in solid neon qualitatively retain the structure of free atoms. Despite the atom-solid interaction, the 6s6p 3P0 level is found to remain metastable with its lifetimes determined to be in the range of ten to hundreds of seconds. The atomic population can be almost completely transferred between the ground level and the metastable level via optical excitation and spontaneous decay. The dynamics of this process is examined and is used to explicitly demonstrate that the transition broadening mechanism is homogeneous.
[en] High ozone concentrations in tropospheric air are usually related to photochemical processes caused by anthropogenic emission on local or regional scales. In the prealpine region, comparable levels may be reached during foehn events as a result of injection of air masses from the free troposphere. From the analysis of meteorological parameters of the foehn episodes wich occurred in 1988 at Ispra and the corresponding ozone levels recorded at the nearby EMEP station, a classification of different events has been attempted. In particular, a correlation between wind speed and ozone level is demonstrated
[en] Gage points are given with the help of which the most commonly required atmospheric diffusion calculations can be carried out rapidly using a simple slide-rule setting; e.g. maximum ground concentration, its distance, and the corresponding effective stack height as functions of the prevailing type of meteorological condition. (author)
[en] Starting from three-hourly measurements, carried out for periods from 5 to 30 years in 135 Italian sites, analytical functions were computed, describing persistencies of wind calm and of winds with intensity higher than any pre-fixed threshold. On the basis of the results obtained, the Italian areas were pointed out, where wind calm and higher-intensity wind are more persistent. Further, an estimation of the feasibility limits was carried out from the results obtained, with respect to the period of measurement analysed
[en] Possibilities of manipulating the Rabi frequency and luminescence rate from degenerate-level systems as well as the velocity of self-induced transparency of multi-level media are studied using a unitary transformation. The Rabi frequency and luminescence rate of an electronic system whose ground level is degenerate and coupled to a resonant mode are found to depend on the level of the degeneracy. The velocity of multi-mode optical solitons in a multi-level medium is found to be influenced by the number of propagating resonant pulses. Physical realizations of relevant systems are proposed
[en] The classical example of problem solving, maximizing the range of a projectile launched from height h with velocity v over the ground level, has received various solutions. In some of these, one can find the maximization of the range R by differentiating R as a function of an independent variable or through the implicit differentiation in Cartesian or polar coordinates. In other papers, various elegant non-calculus solutions can be found. In this paper, this problem is revisited on the basis of the elementary analytical geometry and the trigonometry only. (papers)