RU2714505C1 - Induction synchrotron magnetic system with magnetic field constant in time - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention relates to acceleration engineering and can be used in development of inductive cyclic accelerators with practically constant radius of orbit and constant in time magnetic field. Induction, non-resonant method of acceleration solves the problem of synchronization in a wide range of speeds of accelerated particles and accelerating electric field by changing the repetition frequency of induction pulses. Magnetic system of induction synchrotron has no fundamental limitations on lower energy threshold of accelerated particles. Induction synchrotron magnetic system consists of a set of magnetic dipoles and focusing lenses, which are located on arc-shaped sections of the accelerator housing, and windings of dipoles and lenses are respectively connected to power generators, each dipole contains two components with direct and reverse polarity of magnetic field, thus forming a bipolar magnetic system, and each focusing lens comprises two heteropolar lenses with flat magnetic poles.

EFFECT: technical result is expansion of operating range of accelerated energies and simple process of adjustment and start of accelerator.

1 cl, 3 dwg

Description

Technical field

The invention relates to accelerator technology and can be used in the development of cyclic accelerators with a practically constant radius of the orbit.

State of the art

Known magnetic system of the accelerator, consisting of a set of magnetic dipoles and focusing lenses, which are located on the arcuate sections of the housing of the accelerator and are connected to the power generators of the windings of dipoles and lenses. To keep the radius of the particle’s orbit constant, the magnetic field created by the power generators of the dipole windings must be increasing in time, and the working frequency of the high-frequency accelerating resonators is variable. (See, for example, D.J. Livingood, "Principles of Operation of Cyclic Accelerators" // Publishing House of Foreign Literature, Moscow 1963). Since the tuning range of the resonant frequencies of the resonator is limited, the range of accelerated particle energies is also limited. This circumstance forces the use of additional boosters and pre-accelerators of energy.

The magnetic system of accelerators containing dipoles with a time-constant magnetic field, which, when operating in the particle reflection mode, deflect the particle trajectory by a predetermined angle independent of the particle energy, form closed orbits with a radius that also practically does not depend on the particle energy. The issue of a large range of accelerated energies and the associated large range of cycle repetition rate is solved by changing the cycle frequency of induction accelerating pulses. (Dolbilov G.V. “Induction synchrotron with a constant magnetic field” // RF Patent No. 2608365, and Dolbilov GV “Method for the synchrotron acceleration of charged particles in a constant magnetic field” // RF Patent No. 2618626).

As a prototype, we choose the accelerator magnetic system with a constant magnetic field in time and an almost constant radius of the orbit (G. Dolbilov, “Induction synchrotron with a constant magnetic field” // RF Patent No. 2608365).

However, such a magnetic system has limitations on the magnitude of the lower threshold of particle energy, and the setup and start-up processes of the accelerator are complicated.

Disclosure of Invention

The invention solves the problem of expanding the working range of accelerated energies and, in addition, simplifies the process of setting up and starting the accelerator.

This goal is achieved by the fact that the magnetic system of the induction synchrotron, consisting of a set of magnetic dipoles and focusing lenses, which are located on the arcuate sections of the accelerator body and are connected to power generators through the windings of dipoles and lenses, and each dipole contains two components with direct and reverse polarity of the magnetic fields, and each focusing lens contains two different-polar lenses with flat magnetic poles.

The distinguishing features of the invention are the following: each dipole contains two components with direct and reverse polarity of the magnetic field, and each focusing lens contains two different polar lenses with flat magnetic poles.

The combination of the above characteristics allows us to solve the problem of expanding the working range of accelerated energies by removing restrictions on the lower threshold of energies of accelerated particles and, in addition, to simplify the process of setting up and starting the accelerator.

List of illustrations

FIG. 1 (Appendix) Accelerator circuit;

FIG. 2 (Appendix) Cross-section of bipolar magnetic dipoles of an induction synchrotron;

частиц.FIG. 3 (Appendix) Arrangement of bipolar dipoles and focusing lenses along a conditionally rectified path

particles.

Description of illustrations

In FIG. 1 (Appendix) shows a diagram of an induction synchrotron with a bipolar magnetic system with a constant magnetic field in time, where:

(1) - arcuate sections of the accelerator;

(2) - induction accelerating system;

(3) - straight sections of the accelerator;

(4) - injection system;

(5, 6, and 7) are beam extraction systems.

In FIG. 2 (Appendix) shows a cross-sectional diagram of a bipolar magnetic system, which is located in the arcuate sections of the accelerator, where:

(8) - magnetic poles of the main dipole with direct field polarity;

(9) - magnetic poles of an additional dipole with reverse field polarity;

(10) - a beam injected into an orbit of radius R ₀ ,

(11) - accelerated beam in an orbit of radius R = R ₀ + ΔR (AR / R ₀ << 1).

частиц, где:In FIG. Figure 3 (Appendix) shows the arrangement of bipolar dipoles and focusing lenses along a conditionally rectified path

particles, where:

(12) - dipoles with direct polarity of the magnetic field;

(13) - dipoles with reverse polarity of the magnetic field;

(14) - focusing lenses with flat magnetic poles;

(α) is the angle of the interface of different polar magnetic dipoles.

(S) - the distance between the focusing and defocusing lenses (14)

The implementation of the invention

Particles are injected into an orbit of radius R ₀ (Fig. 2). In this orbit, the total magnetic field of different polar dipoles is zero. Therefore, particles injected into this orbit can, reflected from the fields of different polar dipoles, move in this orbit at an arbitrarily low speed. According to the specifics of cyclic accelerators, with increasing particle velocity during acceleration, an additional, centrifugal force appears, acting on the particles equal to F _c = Mν ² / R, (where M, ν u R is the mass, speed and radius of the orbit). The action of this force is equivalent to the action of a magnetic field of the quantity B _c = Mν / qR (where q is the particle charge). As a result of the action of this centrifugal force (the equivalent magnetic field), the equilibrium orbit, where the total effect of all forces is zero, shifts more and more to the stronger fields of the main dipole. The radius of the equilibrium orbit grows in accordance with the equality R = P / qB, (P is the momentum of the particles) until they are removed from the accelerator.

Small particle vibrations with respect to the equilibrium orbit are stable in the radial y-plane (Fig. 2). The particle wavelength λ is

where: q and P are the charge and momentum of the particle, B ₀ is the magnitude of the induction of the dipole field, η is the coefficient (m ^-1 ), the value of which depends on the specific geometry of the dipoles.

The instability of oscillations in the z - plane is suppressed by a rigid focusing system (see Fig. 3), which contains lenses (3) (G. Dolbilov, “Method for focusing charged particle beams” // RF Patent No. 2633770,). The focal length of such lenses is

The ± sign indicates the focusing or defocusing action of the lens. P and B ₀ are the momentum of the particles and the induction of the magnetic field of the lenses, α is the angle of inclination of the interface of different polar dipoles of the lenses. Oscillations of particles in both y and z - planes are always stable if

where: S is the distance between the focusing and defocusing lenses (14),

α is the angle of inclination of the boundary of different-polar flat lens dipoles (3).

Case Study

The main and additional dipoles of the bipolar magnetic system of the induction synchrotron are electromagnets or permanent magnets. The power source of the electromagnet windings is a direct current generator.

The working surfaces of the magnetic poles of the main and additional dipoles of the bipolar magnetic system of the accelerator can, for example, be a combination of flat and cylindrical surfaces (as shown in Fig. 2) or be hyperbolic (like quadrupole lenses).

The hard-focusing lenses (14) of the magnetic system (Fig. 3) contain flat dipole electromagnets that are connected to direct current sources. Each of the lenses contains two different-polar dipoles, the interface of which is inclined to the axis by an angle α (Fig. 3). The magnitude of this angle affects the stiffness of the focus / defocus. The focusing or defocusing effect of the lenses depends on the polarity of the magnetic field, as well as on the direction of inclination of the interface of different polar dipoles (Fig. 3).

Claims (1)

A magnetic system of an induction synchrotron with a time-constant magnetic field, consisting of a set of magnetic dipoles and focusing lenses that are located on the arcuate sections of the accelerator body, and each dipole and each lens are connected through their windings to their respective power generators, characterized in that each dipole contains two of its components with direct and reverse polarity of the magnetic field, thus forming a bipolar magnetic system, and each focusing lens contains two opposite-polar lenses with flat magnetic poles.

Images