[en] For the purpose of obtaining luminosity of the VLEPP (colliding linearized electron-positron beam) of the order of 10³²cm^-2 per shot, the dynamics of a beam of electrons or positrons injected into the accelerating π-structure of the VLEPP has been unvestigated. The analysis of electric fields of an extended bunch has shown that the selection of a longitudinal distribution of the charge and phase of input into the resonator may provide high energy monochromaticity. For a bunch containing 4x10¹² electrons the selection of energy constitutes 45% at nonmonochromaticity of 4% for 90% of particles. To suppress the resonance instability it is proposed to introduce linear distribution of particle energies along the bunch length. To eliminate th rise of the phase volume caused by the effect of transverse forces it is necessary to introduce the initial energy spread of +-10%. The performed analysis of the effect of inaccurate adjustment of lenses on the excited phase volume demonstrates that to obtain a phase volume of 5x10^-9 cmxrad the lens adjustment tolerance should be about 1 mm

[en] With the aim of studying the stability of operation of superconducting magnetic systems (SMS) in an accelerator radiation field varying in time and space, a semiempirical method is considered of calculating energy release in the SMS, and radiation heating of SMS windings under adiabatic conditions is estimated. A case of azimuthally-uniform particle losses, a case of targets and extraction systems are discussed. Calculations have been performed by the Monte Carlo method. It is shown that even at small losses of particles (0.1%) the pulse radiation heating constitutes a serious problem

[en] Results of work on deVelopment and testing of a thyristor power supply system of the ring electromagnet of the ITEP synchrotron are reported. The system employs a water-cooled module used in industrial converters. In this module the two series-connected branches of thyristors are reconnected into parallel ones. A basic circuit of the system and flowsheets of the channel for the power thyristor control pulse shaping and of the system for monitoring the state of power thyristors are presented. Main characteristics of the thyristor supply system are given: the rectified current is 2.5 kA, the rectified voltage - 10 kV, the shock current through the module - 13.8 kA

[en] For the purpose of studying narrow resonances during experiments on colliding electron-positron beams, a circuit for monochromatization of the colliding beams interaction energy is proposed. As elements producing the vertical energy dispersion the circuit uses electrostatic quadrupole lenses (SKEW-lenses) rotated at 45 deg. The SKEW quadrupole lenses, arranged at intervals equal to the integral number of betatron oscillation half-waves, produce a required excitation of the vertical dispersion function localized in the experimental gap area. Their action results in the appearance of the coupling of oscillations which is compensated for by the lenses connected in opposite polarities. For the VEPP-4 storage the estimate of the energy resolution with connected SKEW-lenses has given 0.86 MeV. For relatively low energies the limit value of the energy resolution can be reduced by introducing additional radiation damping

[en] A diagram is proposed of a high-flux neutron generator which employs a two-frequency linear accelerator of deuterons and is designed to study structural materials of thermonuclear reactors. Between the in ector and the accelerator main part of the Alvarez type there are sections with space-homogeneous strong focussing at a twice lower frequency of the accelerating field. In the final part of the accelerator the beam is focussed by maanetohard quadrupoles. A ''boiling'' lithium target is discussed. In case of a lithium target the theoretical and experimental values of the neutron yield at deuteron energies of 35 MeV fall within the range (1.1-1.5)x10^-2 neutron/deuteron. Estimations of spectral-angular distributions of fast neutrons are given. Results of evaluating temperature fields in the targets are presented. High intensity of the neutron generator beam will make it possible to study the processes of accumulation of fissionable substances in uranium and thorium absorbers which are planned to be used in termonuclear reactor shields

[en] Calculations of admissible pressures of residual gases and admissible beam losses in the vacuum system of a meson factory have been performed to ensure the radiation purity of the accelerating-storage complex of the 600-MeV meson factory. The values of residual gas admissible pressures for different sections of the meson factory are as follows: for the proton injector-8x10^-6 mm Hg, for the initial part of the linear accelerator-1x10^-7 mm Hg, for the injectors of negative ions-1x10^-7 mm Hg, for the main part of the linear accelerator and transport channels H^--5x10^-8 mm Hg, for proton transport channels - 2x10^-6 mm Hg, and for the storage-buncher -1x10^-9 mm Hg. A set of measures is proposed to provide low values of specific gas release. Diagrams of vacuum joints, valves and seals are presented. Preliminary pumping out of the vacuum system is performed by the RBN-6, VN-7MG, 2DVN-500, TMN-200A mechanical pumps, while the continuous one - by magnetodischarge pumps of the NMD-1 type. The vacuum systems can be both manual - and remote-controlled including the employment of computers

[en] Collisional relaxation of a beam in a storage without cooling is considered, illustrated by a collision of two particles at initially radial opposite momenta, which completely convert into longitudinal ones as a result of 90 deg scattering. It is shown that internal scattering may have a pronounced effect on the cooling process provided the time of internal relaxation for a state determined, in the single-particle approximation, by electron beam parameters is of the order or less than the time of electron cooling for degrees of freedom having a minimum friction decrement. Equilibrium beam temperatures at energies below and above the critical one are estimated. It is demonstrated that the internal scattering at below-critical energies may have a positive effect

[en] A description is given of a positron source based on a high-current linear accelerator and the B-4 450 MeV synchrotron for the VEPP-4 storage and the results obtained when testing it are presented. 200 KeV electrons are in ected and accelerated in two sections of the linear accelerator to 7 MeV. In the conversion unit the electrons are focused onto the converter, and the 7 MeV obtained positrons are transferred to the B-4 synchrotron where they are accelerated to 450 MeV. To excite the linac use is made of a gyrocon which converts the energy of the electron beam of the ELIT accelerator into the energy of electromagnetic oscillations. The gyrocon output power of the order of 40 MW has been obtained. The linac makes it possible to obtain an electron beam at 36 MeV. A positron beam has been detected behind the first bending magnet. Tuning the B-4 synchrotron has begun at the 7 MeV electron beam. The electron beam is trapped in the VEPP-3 storage

[en] A circuit designed to excite the electromagnet of a flux-biased betatron is considered, in which the superposed initial magnetization of the central core to the maximum admissible negative value of the magnetic induction is performed by a low-power dc source. As a result the control flux changes from zero to its maximum value, while the accelerating flux changes from the maximum admissible negative value to the admissible positive one. In a 15 MeV betatron with a bremstrahlung dose rate of approximately 0.16 R per pulse at a distance of 1 m the amplitude of the magnetic induction in the central core constitutes 3.5 T. Magnetic measurements have shown that the equilibrium orbit position can be varied over a wide range by changing the value of inductance. The proposed excitation circuit makes it possible to considerably decrease the weight of the betatron electromagnet by making a more complete use of the steel magnetization curve

[en] With a view to measure the longitudinal polarization of beams in electron-positron storages a possibility is considered of utilizing the Compton scattering of hard circularly-polarized photons. A spiral ondulator positioned in an accelerator gap serves as a source of circularly-polarized photons. The photon beam emitted by electrons is used to measure the polarization of positrons and vice versa. It is shown that by periodically changing the direction of the magnetic field in the ondulator it is possible to monitor, by a number of secondary gamma quanta, the degree and sign of longitudinal polarization for each specific beam without its destruction. A possibility is shown of employing the ''top-bottom'' anisotropy in secondary gamma-quanta emission to determine the transverse polarization at electron energies not exceeding several GeV. With the rise of energy the polarization degree can be measured with the help of integral spin resonances