DE1293915B - Cavity resonator for transit tubes or particle accelerators - Google Patents

Description

1 2

The invention relates to a cavity resonator F i g. Fig. 5 shows the characteristic of a cavity for Time-of-flight tubes or particle accelerators, des-resonators, as shown in FIGS. 3 and 4; sen housing part with respect to a longitudinal plane symmetrical F i g. 6 shows a schematic representation of a Irish trained and the a number of longitudinal particle accelerator, in the inventive the cavity resonator axis coaxially one behind the other - 5 cavity resonators are used; contains lying drift tubes, which by in the F i g. 7 shows a longitudinal section through a back named Longitudinal plane arranged transversely to the drift wave oscillator tube with a tube according to the invention extending, rod-shaped elements, the cavity resonator according to the invention.

alternately at opposite points of the line. In the various drawing figures are for housing part are galvanically fastened, supported in this way io designation of the same parts and the same reference numerals, that an interdigital structure results. turns. The in the F i g. 1 and 2 shown cavity resonators of this type are already space resonator has a parallelepipedic known (See USA patents 2,899,595, housing part 1 with a longitudinal axis 2. With respect to 2 891191). this axis has the housing part 1 two rectangular

The aim of the invention is to create a hollow 15-shaped end walls, two large side walls and

space resonator for time-of-flight tubes or particle- two small side walls. Along the axis 2 is

accelerator, by means of which, in comparison to the previous one, either a constant or changeable part

directions, the known cavity resonators distribution having row of coaxially one behind the other

turn, with the same dimensions better electrical lying drift tubes 3 provided, which are made of metal

Tric properties or at the same electrical 20 see rods 4 are held, which alternately

Properties smaller dimensions are achieved on the large side walls are attached. That

can. System of metallic rods 4 thus forms with the

Starting from a cavity resonator of the drift tubes 3, an interdigital structure that leads to the Initially, this task is parallel to the small side walls. A ladder 5, The invention is achieved in that a wave-like shape has its ends on the end walls of the housing part 1 curved, are galvanically fastened in a suitable manner with central beam passage openings provided conductor which curves in a wave shape in one of the cavities, for example in the plane The plane containing the resonator axis extends and the rods 4, and arranged so that it »slalomed Ends on the end walls of the housing part are fastened like galvanically between the successive drifts, runs back and forth between the tubes 3 on top of one another, as shown in FIG. 1 following Drift tubes is alternately back and forth. The wavy curved conductor 5 is runs. provided with central beam passage openings 6.

An advantageous embodiment of the invention The end walls also have openings 7 which

is characterized by the fact that the plane in which the allow the passage of the beam is

wave-shaped curved conductor is arranged, with 35 The in F i g. 3 and 4 shown cavity

the plane in which the rod-shaped elements resonate differs from the design

are arranged, coincides. In this case, according to FIGS. 1 and 2 only because the plane

Quality of the cavity resonator a maximum. in which the wavy curved conductor 5

In a further advantageous embodiment, it is arranged in relation to the plane in which the metallic

the invention is the plane in which the wave 40 rods 4 are arranged, is vertical,

shaped curved ladder is arranged to the plane, According to the theory is to be expected and experiments

in which the rod-shaped elements are arranged, have shown that a cavity resonator of the

perpendicular. In this case, the quality of the hollow in FIG. 3 and 4 shown in a fre-

space resonator a minimum. frequency of 67 MHz has the following features:

According to a further advantageous embodiment 45 _T .. ₁ on

The form of the invention is the plane in which the wave- iw! ^ i ^; «öflisoi, l r \\ i"<n ™

shaped curved ladder is arranged against the 2SAgS ^ about 50 ''

Level in which the rod-shaped elements are arranged ^^ of ^{the Dnitroöre about 5½}

are inclined. F i g. 5 shows the characteristic of such

Another particularly advantageous embodiment 50 cavity resonator. The parallel resistance of the cavity resonator according to the invention was R _s in megohms / cm on the ordinate and that

is characterized in that the wave-shaped delay ratio ^ on the abscissa curved conductor in the area of the beam passage se _v

Openings with ring-shaped coaxial attachments, where c is the speed of light and ν is the visible. 55 Phase velocity of the wave in basic mode

The invention is hereinafter referred to together at the frequency of 67 MHz. These characters

with the drawing, for example. ristics shows high i? _s values close to 50 Meg

F i g. 1 is a longitudinal section through a first output ohm / cm for the band of particular interest

management form of a cavity according to the invention _from JL _{between 2} and 6. The quality ö of the cavity

resonators; 60 ν

F i g. 2 represents a cross section in the line H-II resonators reached a value of the order of magnitude

of the in FIG. 1 shown cavity resonator; of 20 000. The comparison with other well-known

F i g. 3 is a longitudinal section through a second out cavity resonator operating at the same frequency management form of a cavity work according to the invention, shows that with the same electrical self-resonator; 65 shafts load and dimensions known

F i g. FIG. 4 is a longitudinal section through the FIG. 3 cavity resonators much larger or with disparate Cavity resonator along the line with dimensions equivalent to the electrical Eigen-IV-IV in Fig. 3; are far less favorable.

F i g. 6 shows schematically a particle accelerator, for example for heavy ions, in which cavity resonators according to the invention are used are. In this case, the pitch is the drift tubes 3 held by the rod-shaped elements and the delay line formed by the wavy curved conductor 5 is variable to, as is known, the synchronization condition between the phase speed of the shaft and the speed of the accelerated particles.

The in F i g. The particle accelerator shown in FIG. 6 essentially consists of a particle beam 9 supplying particle source 8, a series of cavity resonators 1 and a collector electrode 10. The cavity resonators can according to FIGS. 1 and 2 or according to FIGS. 3 and 4 formed be, or correspond to an intermediate type in which the plane in which the undulating curved Head 5 is arranged, inclined against the plane in which the rod-shaped elements 4 are arranged is.

Drift spaces 11 are provided between the cavity resonators 1, in which the Windings 12 of the magnetic focusing system can be accommodated.

The cavity resonators 1 are excited by ultra-high frequency generators 13 via coupling loops 14. The frequency of these generators can be the same for all cavity resonators. It can, however suitably selected different frequencies can also be used. The cavity resonators are individual connected to pumps 15.

F i g. 7 shows a reverse wave oscillator tube as another application example. Here is the housing part 16 of a cavity resonator of the type shown in FIGS. 1 and 2 type shown at one end with a collector 17 and at the other end with the base 18 which supplies a particle beam 20 Electron gun 19 connected. The constant pitch delay line is in the to the collector 17 adjacent area covered with a damping layer 21, which the forward wave absorb and cause the tube to work as a traveling wave tube. A decoupling loop 22 is arranged on the electron gun 19 side. The windings 23 generate the magnetic Field for beam guidance.

It goes without saying that the invention can also be used with other time-of-flight tubes. In particular the delay line can also operate in a forward mode, thus creating an amplifier can be, the one on the side of the electron gun a coupling loop and on the collector side has a coupling-out loop, the attenuation in a known manner at one for the amplifier appropriate place.

The cavity resonator described can be modified in various ways. For example can open the openings in the wave-shaped curved conductor by rings according to the Drift tubes 3 are replaced.

Claims (5)

Patent claims: 1. Cavity resonator for time-of-flight tubes or particle accelerators, the housing part with respect to a longitudinal plane is formed symmetrically and of a number of along the cavity resonator axis Contains coaxially one behind the other drift tubes, which are arranged by in the said longitudinal plane, transversely to the drift tubes extending, rod-shaped elements that alternate at opposite points of the housing part are galvanically fastened, are held in such a way that an interdigital structure results, characterized in that a wave-shaped curved, with central beam passage openings (6) provided conductor (5), which is contained in a cavity resonator axis (2) Plane extends and its ends on the end walls of the housing part (1) galvanically are attached, alternately runs back and forth between the successive drift tubes (3). 2. Cavity resonator according to claim 1, characterized in that the plane in which the wave-shaped curved conductor (5) is arranged, with the plane in which the rod-shaped elements (4) are arranged to coincide. 3. Cavity resonator according to claim 1, characterized in that the plane in which the wave-shaped curved conductor (5) is arranged, to the plane in which the rod-shaped elements (4) are arranged, is vertical. 4. Cavity resonator according to claim 1, characterized in that the plane in which the wave-shaped curved conductor (5) is arranged against the plane in which the rod-shaped elements (4) are arranged, is inclined. 5. Cavity resonator according to one of the preceding claims, characterized in that that the wavy curved conductor (5) in the area of the beam passage openings (6) with annular coaxial lugs is provided. 1 sheet of drawings