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A new high precision measurement of the $J/\psi$- and $\psi'$-meson masses has been performed at the VEPP-4M collider using the KEDR detector. The resonant depolarization method has been employed for the absolute calibration of the beam energy. The following mass values have been obtained: $M_{J/\psi} = 3096.917 \pm 0.010 \pm 0.007$ MeV, $M_{\psi'} = 3686.111 \pm 0.025 \pm 0.009$ MeV. The relative measurement accuracy has reached $4. 10^{-6}$ for $J/\psi$ and $7. 10^{-6}$ for $\psi'$, approximately 3 times better than in the previous precise experiments., Comment: 12 pages, 4 tables, 10 figures

First results on polarization measurement are presented. More sophisticated scheme of polarimeter is proposed. It is expected that the accuracy of the measurement of polarization of the circulated electron beam of about 20% will be achieved during 8 minutes of operation of this Moller polarimeter. The work was supported by Russian Foundation for Basic Researches, grants 98-02-17949 and 98-02-17993, INTAS, grant 96-0424 and State Scientific and Technical Programm (Nuclear Physics).

Experiments with the MD-1 detector at the VEPP-4 collider in the energy region of Υ mesons were carried out in 1980–1985. Some of the MD-1’s results are still among the most accurate: precise measurement of Υ(1S), Υ(2S) and Υ(3S) meson masses; leptonic widths of Υ(1S) and Υ(2S); R ratio in the energy region s=7.2–10.3 GeV; upper limits on the Υ(1S) decays to pp, K+K−, π+π−; upper limit on the electron width of new resonances in the energy region 7.2–10.3 GeV. New values of Υ(1S), Υ(2S), and Υ(3S) masses corrected to change of the electron mass are given.