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The status of the experiment on the precise $\tau$ lepton mass measurement running at the VEPP-4M collider with the KEDR detector is reported. The mass value is evaluated from the $\tau^+\tau^-$ cross section behaviour around the production threshold. The preliminary result based on 6.7 pb$^{-1}$ of data is $m_{\tau}=1776.80^{+0.25}_{-0.23} \pm 0.15$ MeV. Using 0.8 pb$^{-1}$ of data collected at the $\psi'$ peak the preliminary result is also obtained: $\Gamma_{ee}B_{\tau\tau}(\psi') = 7.2 \pm 2.1$ eV., Comment: 6 pages, 8 figures; The 9th International Workshop on Tau-Lepton Physics, Tau06

The status of the experiment on the precise τ lepton mass measurement running at the VEPP-4M collider with the KEDR detector is reported. The mass value is evaluated from the τ + τ − cross section behavior around the production threshold. The preliminary result based on 15.2 pb −1 of data is m τ = 1776.69 −0.19 +0.17 ± 0.15 MeV .

High precision mass measurements in $\Psi$ and $\Upsilon$ families performed in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited. The corrections for the new value of the electron mass are presented. The effect of the updated radiative corrections has been calculated for the $J/\Psi(1S)$ and $\Psi(2S)$ mass measurements.

Recent USSR legislation governing the Soviet exclusive economic zone is reviewed. Soviet municipal legislation on pollution control is compared against the provisions of the 1982 Law of the Sea (LOS) Convention, and points of noncompliance are identified. The method stipulated in Soviet legislation for calculating losses caused by pollution is highlighted as an area of special concern.

This article looks at how in various parts of the seas and oceans the marine environment has been subjected to pollution, the vulnerability to which also varies depending on oceanographical and ecological conditions. Consequently, the international norms and standards intended for universal application with regard to preventing pollution of the sea from ships may prove to be inadequate to protect the marine environment of individual areas of the oceans.

The analytical and numerical investigations of trajectories of the probe beam electrons in the two dimensional wakefield, excited in plasma by a dense bunch of relativistic electrons with Gauss longitudinal and transverse distribution of density is carried out. On the basis of calculations of probe beam deviations, the diagnostic instrument is developed for parameters of experiments conducted in NSC KIPT. The diagnostic instruments consist of an electron gun forming the electron beam with energy 10 KeV, current 10 /spl mu/A and diameter 2 mm which passes through the chamber of interaction and falls on a collector of diameter 10 mm. A collector (screen) is placed in front of the first plate of a microchannel amplifier which consists of three microchannel plates (MCP) with sizes 20-30 mm. The voltage of 3 kV was applied to each plate. Total amplification of MCP amplifier is 10/sup 4/-10/sup 5/ in dependence on quantity of particles, falling on the first plate. As a result the deviations of probe beam by excited wakefield the electrons fall on the first plate of the amplifier and are registered by the anode of the amplifier, located behind the third plates. Calculated probe beam deviations and obtained amplification of MCP amplifier permit investigation of the electrical wakefields, excited by the sequence of relativistic bunches (number of particles in bunch is 2/spl middot/10/sup 9/, energy is 14 MeV) in plasma of density 10/sup 11/-10/sup 13/ cm/sup -3/. The maximal value of the fields registered by such a technique is not less 2 kV/cm.