CN209312710U - A kind of THERMIONIC CATHODE MICROWAVE ELECTRON GUN inhibiting high-order mode electromagnetic field - Google Patents

Abstract

The utility model relates to a kind of THERMIONIC CATHODE MICROWAVE ELECTRON GUNs for inhibiting high-order mode electromagnetic field, including half chamber, whole chamber and coupling edge chamber to link together；Half chamber is equipped with cathode, and top is equipped with half chamber coupling aperture, and bottom is equipped with half chamber corresponding with the half chamber coupling aperture and couples symmetrical holes；The waveguide aperture for being respectively equipped with coupling aperture on the whole chamber, being connected with waveguide, the whole chamber corresponding with the waveguide aperture are equipped with guide symmetry hole；The middle part of the whole chamber and half chamber is equipped with electron beam channel, and the end of the electron beam channel is equipped with electron beam outlet；The top of half chamber and the whole chamber is connected by the half chamber coupling aperture, the coupling aperture with the coupling edge chamber respectively, it is characterised in that: the whole bottom of chamber portion is equipped with whole chamber corresponding with the coupling aperture and couples symmetrical holes.The utility model reduces second order mode and influence of the quadravalence mould to quality of beam, improves electron beam quality of beam by way of aperture symmetrical in resonant cavity.

Description

A kind of THERMIONIC CATHODE MICROWAVE ELECTRON GUN inhibiting high-order mode electromagnetic field

Technical field

The utility model relates to THERMIONIC CATHODE MICROWAVE ELECTRON GUN technical field more particularly to a kind of inhibit high-order mode electromagnetic field THERMIONIC CATHODE MICROWAVE ELECTRON GUN.

Background technique

THERMIONIC CATHODE MICROWAVE ELECTRON GUN is a kind of electron beam generating device of large charge amount short pulse, by most countries Paid attention to, and produce considerable scientific research value and social benefit in each main scientific research country, it is widely used in high energy In the scientific researches such as electron accelerator is built, middle low-energy electron beam line generates.The hot cathode that foreign countries generate for electron beam Microwave electron gun mainly uses APS type classical architecture, because the structure has, beam intensity is big, the quantity of electric charge is high, the cathode longevity Many advantages, such as long, easy to maintain, safety is good is ordered, therefore various types of tests have used APS type with high-energy electron accelerator One of the main equipment that THERMIONIC CATHODE MICROWAVE ELECTRON GUN is generated as electron source.

Electron beam is drawn although APS type THERMIONIC CATHODE MICROWAVE ELECTRON GUN is generated electron beam and rolled into a ball and pass through microwave field using hot cathode Out, the macro pulse quantity of electric charge of electron beam and in terms of occupy some superiority, but due to its structure and microwave electricity The reason of field coupling, second order mode and quadravalence mould electromagnetic field can produce bigger effect quality of beam.

Utility model content

The technical problem to be solved by the utility model is to provide a kind of inhibition high-order modes for improving electron beam quality of beam The THERMIONIC CATHODE MICROWAVE ELECTRON GUN of electromagnetic field.

To solve the above problems, a kind of hot cathode microwave electron for inhibiting high-order mode electromagnetic field described in the utility model Rifle, including half chamber, whole chamber and coupling edge chamber to link together；Half chamber is equipped with cathode, and top is equipped with half chamber and couples Hole, bottom are equipped with half chamber corresponding with the half chamber coupling aperture and couple symmetrical holes；Coupling is respectively equipped on the whole chamber Hole, the waveguide aperture for being connected with waveguide, the whole chamber corresponding with the waveguide aperture are equipped with guide symmetry hole；The whole chamber and described The middle part of half chamber is equipped with electron beam channel, and the end of the electron beam channel is equipped with electron beam outlet；Half chamber and the whole chamber Top be connected respectively by the half chamber coupling aperture, the coupling aperture with the coupling edge chamber, it is characterised in that: the whole chamber Bottom is equipped with whole chamber corresponding with the coupling aperture and couples symmetrical holes.

Compared with the prior art, the utility model has the following advantages:

The utility model is symmetrical using intracavitary coupling aperture on the basis of existing APS type THERMIONIC CATHODE MICROWAVE ELECTRON GUN design scheme The improved procedure of place's aperture devises novel THERMIONIC CATHODE MICROWAVE ELECTRON GUN, and the type microwave electron gun passes through symmetrical in resonant cavity The mode of aperture reduces second order mode and influence of the quadravalence mould to quality of beam, improves electron beam quality of beam, is a kind of right The significant improvement of classical APS type microwave electron gun.

Detailed description of the invention

Specific embodiment of the present utility model is described in further detail with reference to the accompanying drawing.

Fig. 1 is the structural schematic diagram of the utility model.

Fig. 2 is the sectional view of the utility model.

Fig. 3 is the side view of the utility model.

Fig. 4 is the utility model electron gun microwave property.

Fig. 5 is the electric field that the utility model corresponds to pi/2 mould.

Fig. 6 is the magnetic field that the utility model corresponds to pi/2 mould.

Fig. 7 is field distribution on the utility model axis.

Fig. 8 is the utility model multistage field component strength test position.

Fig. 9 is the normalization of the utility model each positionComponent.

Figure 10 is that the utility model electron gun exports beam behaviour (A) Energy distribution (B, C, D) phase-space distributions.

In figure: 1-half chamber；2-whole chambers；3-coupling edge chambers；4-half chamber coupling aperture；5-half chamber couples symmetrical holes；6— Coupling aperture；7-waveguides；8-guide symmetry holes；9-electron beam outlets；10-whole chambers couple symmetrical holes.

Specific embodiment

As shown in Fig. 1 ~ 3, a kind of THERMIONIC CATHODE MICROWAVE ELECTRON GUN inhibiting high-order mode electromagnetic field, including link together half Chamber 1, whole chamber 2 and coupling edge chamber 3.Half chamber 1 is equipped with cathode, and top is equipped with half chamber coupling aperture 4, and bottom is equipped with and half chamber coupling It closes corresponding half chamber in hole 4 and couples symmetrical holes 5；The waveguide aperture for being respectively equipped with coupling aperture 6 on whole chamber 2, being connected with waveguide 7, with this The corresponding whole chamber 2 of waveguide aperture is equipped with guide symmetry hole 8；The middle part of whole chamber 2 and half chamber 1 is equipped with electron beam channel, the electronics The end of beam passage is equipped with electron beam outlet 9；The top of half chamber 1 and whole chamber 2 passes through half chamber coupling aperture 4, coupling aperture 6 and coupling respectively Side chamber 3 is closed to be connected；Whole 2 bottom of chamber is equipped with whole chamber corresponding with coupling aperture 6 and couples symmetrical holes 10.

There is difference when the state of electron gun and processing assemble when due to actual motion, needs to examine when designing electron gun Worry is adjusted design object (mainly frequency), as shown in table 1.In the target frequency of design and process electron gun It is set as 2855.6MHz.

Frequency values of 1 electron gun of table under different conditions

Since hot-cathode electric rifle uses side coupled structure, it is therefore desirable to it establishes threedimensional model and carries out microwave designing, it is every Dimensional parameters are as shown in Figure 4.

Board design is carried out by F module, main analog result is shown in Table 2 and Fig. 4.

2 electron gun three dimensional design result of table

The electric and magnetic fields distribution of corresponding pi/2 mould is as shown in Figure 5, Figure 6, it can be found that electromagnetic field phase in half chamber and whole chamber Phase difference of pi, and there is no electromagnetic fields in the chamber of side.On axis field distribution (referring to Fig. 7) be adjusted to enhancing half chamber maximum field strength ratio be 1.64, this is to require to design according to Dynamics Optimization.

In order to preferably optimize the emittance of electron gun outlet, by adding and adjusting coupling aperture in the design of electron gun Inhibit multistage field.As shown in figure 8, there is angular asymmetric, introducing in whole chamber due to having opened waveguide aperture and coupling aperture in whole chamber Second component causes electron gun outlet beam group to there is whole transverse momentum, in order to inhibit the effect of this second level field component, Whole chamber coupling symmetrical holes are introduced in electron gun, and have adjusted the symmetrical holes size in the symmetrical holes and half chamber on waveguide opposite (in strict accordance with the length and width in whole cavity waveguide hole in its whole intracavitary symmetrical place's aperture).

Three circles that axially different position radius is 10mm in selected electron gun, as shown in figure 8, two of them circle is in half chamber Near the nose cone of whole chamber, another is at whole chamber center.On these three circlesComponent is the design of criteria optimization electron gun, Its second level field component is set to become smaller, as shown in Fig. 9 and table 3.It can be found that in addition to there is slightly height in the level Four field in half chamber, in whole chamber Second level field reduce a magnitude, can significantly reduce second level field introducing transverse momentum.

3 each position multistage field component of table

A RF period, that is, 350ps time longitudinal homogeneous beam group is simulated using OPAL-T to study the fortune of electronics It is dynamic.Microwave field file used in it is simulated to obtain by CST, while considering space charge effect in simulations.Major parameter It is shown in Table 4.

Table 4

Figure 10 reflects the Energy distribution (under different field strength) at electron beam outlet, and the direction XY is spatial distribution and X, The respective phase-space distributions of Y-direction.

Claims (1)

1. a kind of THERMIONIC CATHODE MICROWAVE ELECTRON GUN for inhibiting high-order mode electromagnetic field, including half chamber (1), the whole chamber (2) to link together With coupling edge chamber (3)；Half chamber (1) be equipped with cathode, top be equipped with half chamber coupling aperture (4), bottom be equipped with it is described Corresponding half chamber coupling symmetrical holes (5) of half chamber coupling aperture (4)；It is respectively equipped with coupling aperture (6) on the whole chamber (2), is connected with The waveguide aperture of waveguide (7), the whole chamber (2) corresponding with the waveguide aperture are equipped with guide symmetry hole (8)；The whole chamber (2) It is equipped with electron beam channel with the middle part of half chamber (1), the end of the electron beam channel is equipped with electron beam outlet (9)；Described half The top of chamber (1) and the whole chamber (2) passes through the half chamber coupling aperture (4), the coupling aperture (6) and the coupling edge chamber respectively (3) it is connected, it is characterised in that: whole chamber (2) bottom is equipped with whole chamber corresponding with the coupling aperture (6) and couples symmetrical holes (10).