CN107371319B

CN107371319B - Compact cyclotron

Info

Publication number: CN107371319B
Application number: CN201710324759.9A
Authority: CN
Inventors: M·阿布斯; S·德诺伊特
Original assignee: Ion Beam Applications SA
Current assignee: Ion Beam Applications SA
Priority date: 2016-05-13
Filing date: 2017-05-10
Publication date: 2019-05-10
Anticipated expiration: 2037-05-10
Also published as: CA2965643C; CA2965643A1; CN207083269U; EP3244710A1; JP2017204470A; EP3244710B1; CN107371319A; JP6249542B2

Abstract

The present invention relates to the compact isochronism sector-focused cyclotrons compared with the cyclotron of the identical energy of the prior art with reduced size and weight.The cyclotron includes two magnetic poles 2 in indoor facing each other, and the room is limited by including magnetic yoke and the flux time yoke 6 of substrate 5.The magnetic pole includes the mound fan block 3 being alternately distributed around central axis Z and paddy fan block 4.The bottom of the paddy fan block is limited by paddy peripheral edge 4vp and including deep pool opening 11, and the deep pool opening extended the substrate.The antelabium of the deep pool opening is located in away from corresponding paddy peripheral edge certain distance L ap.The flux, which returns yoke 6, has thickness Tv in the part towards paddy fan block, so that ratio (Lap × Tv)/Lv²< 5%, wherein each of Lap, Tv and Lv are measured along deep longitudinal axis Lar.

Description

Compact cyclotron

Invention field

The present invention relates to cyclotrons.In particular it relates to which the convolution with the identical energy of the prior art accelerates Device, which compares, has the compact isochronism sector-focused cyclotron of reduced size and weight.

Technical background

Cyclotron be a kind of round particle accelerator, wherein negatively charged particle or positively charged particle along spiral path from The center of cyclotron accelerates the energy until several MeV outward.In isochronous cyclotron, the particle beams is with identical Time passes through each successive cycle of spiral path or a part of circulation.Unless otherwise specified, term " cyclotron " exists For referring to isochronous cyclotron in the following contents.Cyclotron is used for various fields, such as controls for nuclear physics, medical treatment It treats, such as proton therapy, or is used for radiopharmacy.Specifically, cyclotron, which can be used for producing, is suitable for PET imaging The short life positive electricity of (single photon emission computed tomography) is imaged in (Positron Emission Tomography) and SPECT Son transmitting isotope.

Cyclotron includes several elements, and the radio frequency (RF) including injected system, for accelerating charged particle accelerates System, for along the exact path guidance magnetic system of accelerated particle, the extraction system for collecting the particle so accelerated and For the vacuum system of vacuum to be created and maintained in cyclotron.

Between the particle beams is introduced at or near the cyclotron center with relatively low initial velocity by injected system In gap.The particle beams is accelerated and by the magnetic field of magnetic system generation by RF acceleration system along institute in order and repeatedly The spiral path stated in gap guides outwardly.When the particle beams reaches its target energy, by providing the extraction system in leading point System draws the particle beams from cyclotron.The extraction system may include the stripper being for example made of thin graphite flake. For example, passing through the H of stripper^-Ion loses two electronics and becomes positive.Therefore, the curvature in their path in magnetic field Change its symbol, and therefore draws the particle beams from cyclotron towards target.It is well-known that there are those skilled in the art Other extraction systems.

Magnetic system generates magnetic field, and the magnetic field guides charged particle beam along spiral path and makes its focusing, until itself plus Speed arrives its target energy (referring to fig. 4 and Fig. 5).In the following contents, term " particle ", " charged particle " and " ion " is as same Use to adopted word indistinction.It is produced in the gap limited between these poles by two electromagnetic coils being wrapped on two magnetic poles Magnetisation field.The magnetic pole of cyclotron is often divided into alternate mound fan block and paddy fan block around central axis distribution.Two magnetic Gap between pole is smaller at the fan block of mound and larger at paddy fan block.Therefore mound fan block in gap in create high-intensity magnetic field and Weaker magnetic field is created in the gap in paddy fan block.This kind of azimuthal magnetic field variation provides the radial direction of the particle beams and gathers vertically It is burnt.For this reason, this kind of cyclotron is sometimes referred to as sector-focused cyclotron.In some embodiments, mound is fanned Block have with fan block geometry round as a cake, have towards central axis it is generally radially extending first and the Two side surfaces, generally curved peripheral surface, the center surface adjacent with central axis and the side for limiting the gap Upper surface.Upper surface (referring to Fig. 1 (b) and Fig. 3) is delimited by the first and second side edges, peripheral edge and center edge.

In order to maintain vacuum in gap and in order to control and accommodate in the gap and the space of a pair of of magnetic pole Magnetic field, cyclotron further include magnetic yoke.Magnetic yoke is formed by the first and second substrates perpendicular to central axis Z, the substrate Yoke is returned each other by flux to separate.First and second substrates and flux return yoke and limit a room together, and wherein flux returns yoke shape It at the outer wall of cyclotron and is to be contained in cyclotron by the magnetic field control outside coil.First and second magnetic Pole is contained in the interior.First and second substrates are equipped with the opening for the room and vacuum pump to be in fluid communication.

Flux returns yoke and is usually formed by two parts of the horizontal connection in the mesion perpendicular to central axis Z, from And allow to by moving together first substrate and flux Hui E first part and the first magnetic pole far from the second substrate, flux Yoke second part and the second magnetic pole are returned to open cyclotron.Flux, which returns yoke, must have minimum thickness Tv, to close back The magnetic field that magnetic pole outside gap generates simultaneously is contained in cyclotron by rotation accelerator.

Cyclotron is weigh tens tons of big quality and an equipment for large volume.Certainly, this to production cost with And there is influence on the transport of cyclotron and landed cost.Standard Intermodal container is with the width of about 2.4m and similar Highly, and bigger container, such as 40 '-and 45 '-type high cube containers, reach the height of about 2.7m.For the standard of being mounted in In intermodal container, cyclotron must be in the crate less than 2.4m (or 2.7m).Low energy cyclotron Size is such as suitable for accelerating the cyclotron of 18MeV proton, the usually more than size of standard Intermodal container, wherein magnetic Yoke diameter about 2m and hydraulic system is located in outside magnetic yoke.It is required that using the large volume cyclotron of non-standard container and big Weight cyclotron has detrimental effect to the cost of cyclotron and carrying together.

Therefore the art still needs to provide a kind of light-weight and small size isochronism sector focusing convolution acceleration Device, to reduce production and transportation cost and enhance the carrying simplification of this kind of cyclotron.

Summary of the invention

The invention proposes a kind of for being substantially reduced the solution of the volume and weight of cyclotron.In the present invention Detailed description in more detailed description advantage and other advantages of the invention.

The present invention is defined with appended independent claims.Preferred embodiment is defined in the dependent claims.

The present invention relates to a kind of for making the particle beams include the cyclotron accelerated on given path in gap, The cyclotron includes:

(a) it is limited to the room in magnetic yoke, wherein the magnetic yoke perpendicular to central axis Z and each other by flux by returning The first and second substrates that yoke separates are formed, and the flux returns the lateral outer wall that yoke limits the cyclotron,

(b) the first and second magnetic pole, the magnetic pole be located at it is described indoor and about perpendicular to the central axis Z just Middle face is symmetrically positioned to opposite to each other, and the gap that is separated from each other, and wherein, in first and second magnetic pole Each includes,

(c) at least N=3 mound fan block and equal number of paddy including bottom surface with upper surface (3U) fan block, institute It states mound fan block and paddy fan block is alternately distributed around the central axis Z, so that first and second magnetic pole is separated The gap opened includes mound gap portion and paddy gap portion, and the mound gap portion is the upper table in two opposite mound fan blocks Limiting between face and have the mean gap height Gh that measures along the central axis Z, the paddy gap portion is two It is being limited between the bottom surface of a opposite paddy fan block and there is the average paddy clearance height Gv measured along the central axis Z, Wherein Gv > Gh；

(d) bottom surface of each paddy fan block is limited by paddy peripheral edge, and the paddy peripheral edge is with first and second Lower distal end is boundary, and edge that be defined as the bottom surface, that position is farthest from the central axis Z；

(e) bottom surface of each paddy fan block further comprises deep opening, and the deep pool opening extends through the magnetic yoke The thickness of substrate and limit height and be Ga, be at least five times of Gh big deep gap portions, the deep pool opening have perpendicular to The central axis, the section limited by deep circumference, the deep pool circumference and the paddy peripheral edge separate edge and the center The shortest distance Lap that the deep longitudinal axis Lar that axis Z intersects vertically is measured, and wherein, the paddy peripheral edge and it is described in Mandrel line Z separates the distance Lv measured along the deep pool longitudinal axis Lar；

(f) flux, which returns yoke, has the wall thickness changed with the Angle Position around the central axis, wherein along every The deep longitudinal axis Lar of a paddy fan block measures minimum wall thickness value Tv；

It is characterized in that, the distance Lap of deep circumference to the paddy peripheral edge of each paddy fan block is returned multiplied by the flux The product of yoke thickness Tv and the peripheral edge to the central axis Z distance Lv square ratio (Lap × Tv)/Lv²It is small In 5%, preferably less than 3%, even more preferably less than 2%, more preferably less than 1%.

The size and location of the deep pool opening is important.Preferably, it is described deep pool opening diameter 2Ra with along the deep pool The ratio by the paddy peripheral edge (4vp) and the central axis Z distance Lv separated that longitudinal axis Lar is measured Rate 2Ra/Lv is included between 45% and 60%, preferably between 48% and 55%.It is described deep pool opening diameter 2Ra with it is described The ratio 2Ra/La of the distance between the center of central axis Z and deep opening section La be La value at least 60%, preferably extremely Few 65%, more preferably at least 70%, and wherein, the diameter 2Ra of the deep pool opening is preferably incorporated in 240mm and 300mm Between.

The thickness Tv that flux towards paddy returns yoke also depends on the size of average paddy clearance height and magnetic pole.Specifically, it puts down Equal paddy clearance height Gv returns the product Gv × Tv and peripheral edge to square of central axis Z distance Lv of yoke thickness Tv multiplied by flux Ratio (Gv × Tv)/Lv²It can be less than 20%, preferably less than 15%, even more preferably less than 10%.

Because of the focusing effect enhanced due to deep pool opening, it is possible to using more shallow than prior art cyclotron Paddy, for the size of population of cyclotron and weight, this is favourable.For example, the average mound gap of mound gap portion is high The height ratio Gh/Gv for spending the average paddy clearance height Gv of Gh and paddy gap portion may include between 8% and 20%.Together When, pass through the particle beam of enhancing, so that it may realize than applied narrower gap so far.Specifically, the mound gap Height product and the periphery of the partial average mound clearance height Gh multiplied by the average paddy clearance height Gv of the paddy gap portion Edge to the central axis Z distance Lv square ratio (Gh × Gv)/Lv²Less than 5%, preferably less than 3%, it is more excellent Selection of land is less than 2%.The average mound clearance height Gh of the mound gap portion may include between 20mm and 27mm, preferably exist Between 22mm and 26mm.The average paddy clearance height Gv of paddy gap portion may include between 100mm and 500mm, preferably Between 150mm and 400mm, preferably between 200mm and 250mm.

In general, broader paddy can be used, so that first He of for example described paddy peripheral edge (4vp) Second lower distal end (3lde) and the central axis are Z-shaped at paddy azimuth angle alpha v so that the average mound clearance height Gh with The ratio Gh/tan (α v) of the azimuthal tangent value tan (α v) of paddy is no more than 30mm, preferably not more than 27mm.Specifically Ground, the paddy azimuth angle alpha v can be greater than 35 °, preferably more than 40 °, more preferably larger than 42 °, and also less more than 50 °, Preferably no more than 46 °, no more than 45 °.

The flux return yoke include faced chamber inner surface and outer surface, the outer surface away from the room and with institute Inner surface is stated to separate with the wall thickness that the flux returns yoke.In the preferred embodiment of cyclotron according to the present invention, including N =4 or 8 mounds fan blocks and equal number of paddy fan block, the section perpendicular to the central axis Z of the inner surface have with The central axis Z concentric circular geometry, and the section perpendicular to the central axis Z of the outer surface has The geometry being inscribed in the square concentric with the central axis Z, the edge-perpendicular is in the deep diameter of four paddy fan blocks To axis Lar, and preferably cut away turning.

It is more cost-efficient be if the substrate, magnetic pole and flux return yoke be all manufactured from the same material and The multiple portions that the substrate and flux return yoke have the identical height measured along the central axis, so that from same Produced in one batch of material cyclotron structure so main element.

Detailed description of the invention

These of the invention will pass through way of example with further aspect and be explained in more detail with reference to attached drawing, attached In figure:

Fig. 1 schematically shows (a) lateral sectional view and (b) top view of cyclotron according to the present invention.

Fig. 2 shows the top views that the paddy of two embodiments according to the present invention fan block and flux return a part of yoke.

The local perspective view that Fig. 3 shows half of cyclotron (in order to enhance visibility, is not shown flux and returns in yoke and draw The outlet of particle out).

Fig. 4 shows the schematic diagram from the path that the particle that the central area of magnetic pole accelerates to leading point is followed.

Fig. 5 schematically shows mound gap portion, paddy gap portion and deep gap portion (abyss gapportion) In or outer magnetic field shape and intensity.

It is described in detail

The present invention relates to isochronism sector-focused cyclotrons, hereinafter referred to discuss in the above background of technology Type cyclotron.Cyclotron according to the present invention makes charged particle along spiral path 12 from cyclotron Central area accelerates to be brought out until them with several MeV energy outward.For example, the charged particle so drawn can be proton H⁺Or deuteron D⁺.Preferably, the energy that the particle of extraction reaches is included between 10MeV and 26MeV, more preferably in 15MeV Between 21MeV, most preferably 18MeV.The cyclotron of this kind of energy is suitable for being imaged in PET for such as production (Positron Emission Tomography) and SPECT are imaged short-lived used in (single photon emission computed tomography) Order Positron emitting isotopes.

As shown in Fig. 1 (a), cyclotron 1 according to the present invention includes by two substrates 5 and being formed together the logical of yoke Measure go back to the room of the formation of yoke 6.As shown in Fig. 1 (a) and Fig. 5, flux returns the outer wall of yoke formation cyclotron and will be outside coil Magnetic field control is to be contained in cyclotron.Magnetic field is contained in the minimum for being determined that flux returns yoke 6 in cyclotron Thickness Tv depends on the intensity in the magnetic field outside gap 7.

Cyclotron further comprises the first and second magnetic poles 2 in the room, the magnetic pole about perpendicular to The mesion MP of central axis Z symmetrically facing each other and the certain interval 7 that is separated from each other.The yoke and magnetic pole are all by magnetism Material, preferably low-carbon (C) steel is made and forms a part of magnetic system.Magnetic system is by that will be made of an electrically conducting material First and second coils 14, which are wrapped on the first and second magnetic poles and cooperate, to be included between the magnetic pole and flux time yoke Room annular space in complete.

As shown in Fig. 1 (b) and Fig. 4, each of first and second magnetic poles 2 include radially dividing around central axis Z At least N=3 mound fan block 3 of cloth (Fig. 1 (b) and Fig. 4 illustrate the preferred embodiment of N=4).As shown in Fig. 1 (b) and Fig. 3, often A mound fan block 3 (light shadow region is expressed as in Fig. 1 (b)) has the upper surface 3U extended within the scope of the azimuth angle alpha h of mound.First It further comprise fanning 4 (Fig. 3 of block around the paddy of the radially-arranged same number N of central axis Z with each of the second magnetic pole 2 In be expressed as shadow region).Each paddy fan block 4 flanks what two mounds fan blocks 3 and having extended within the scope of paddy azimuth angle alpha v Bottom surface 4B, so that α h+ α v=360/N.As the bottom surface of Fig. 1 (b) and demonstrated in Figure 2, paddy fan block further wrap Include the deep pool opening 11 for the whole thickness for extending through magnetic yoke.Need this kind of opening come for the room to be fluidly connected to vacuum Pump.As then will be discussed in greater detail, significantly reduce cyclotron using the presence of this kind of opening in the present invention Overall dimension and weight.

The mound fan block 3 and paddy fan block 4 of first magnetic pole 2 fan block 3 and paddy fan block 4 respectively for the opposite mound of the second magnetic pole 2.Figure Path 12 along the particle beams shown in 4 includes in the gap 7 for separating the first magnetic pole with the second magnetic pole.First and second Therefore gap 7 between magnetic pole includes:

Mound gap portion 7h, the mound gap portion are limited between the upper surface 3U of two opposite mound fan blocks 3 And there is mean gap height Gh, mean gap height is defined as mound gap portion two opposing upper 3U's Average height on region,

Paddy gap portion 7v, the paddy gap portion are limited between the bottom surface 4B of two opposite paddy fan blocks 4 And there is mean gap height Gv in the paddy gap portion, the mean gap height is defined as paddy gap portion and exists Average height on the region (except deep pool opening 11) of two opposite bottom surface 4B,

Deep gap portion 7a, the deep pool gap portion be limited between paddy fan two of block relatively deep pool opening and With the mean gap height Ga for being significantly greater than Gv and Gh.

Average mound and paddy clearance height are accordingly measured as on the entire upper surface and lower surface of mound fan block and paddy fan block Clearance height average value.The average value of paddy clearance height has ignored the deep pool opening on bottom surface.

As shown in Fig. 1 (b) and Fig. 3, upper surface 3U is limited by the following terms:

Upper peripheral edge 3up, the upper peripheral edge are defined using distal end 3ude on first and second as boundary For upper surface, edge that position is farthest from central axis Z；

Upper center edge 3uc, the upper center edge as boundary and are defined using proximal end 3upe on first and second For the upper surface, edge that position is nearest from the central axis；

First upper edge 3ul, first upper edge by described first distal end and described first on proximal end phase Connection；

Second upper edge 3ul, second upper edge by described second distal end and described second on proximal end phase Connection.

It should be noted that property purpose for clarity, be not shown in the upper edge that the flux that Fig. 1 (b) and Fig. 3 is indicated returns yoke 6 Extraction channel.It should be clear that such as the flux of the well-known cyclotron according to the present invention of those skilled in the art Returning yoke includes the extraction channel for allowing the particle beams to leave cyclotron, and it does not need to be more fully described herein.

Mound fan block 3 further comprises (referring to Fig. 3):

First and second side surface 3L, each side surface extend transversely to be located at mound from the first and second upper edges Fan the bottom surface of the correspondence paddy fan block of the either side of block, thus by the first and second lower edge 3ll be limited to make side surface with The edge of adjacent bottom surface intersection, the lower distal end that first and second lower edge respectively has position farthest from central axis 3lde；

Peripheral surface 3P, the peripheral surface extend to lower peripheral edge 3lp, the lower periphery sides from upper peripheral edge Edge is defined as using the lower distal end 3lde of the first and second lower edges as the section on boundary.

The average height Hh of mound fan block is being averaged of being parallel to that central axis measures between lower edge and upper edge Distance.

Similarly, valley points 4 be limited by bottom surface 4B, two sides side connects with the side surface 3L of adjacent mound part.Paddy Partial bottom surface is therefore using the lower edge 3ll of the adjacent side and paddy peripheral edge 4vp as boundary, outside the paddy Peripheral edge is defined as using the lower distal end 3lde of the lower edge as the section on boundary.Paddy peripheral edge 4vp is defined as paddy fan The bottom surface of block, edge that position is farthest from central axis Z.

Deep pool opening 11 is located in valley point, and in the valley point, the deep pool opening is to the highfield in the gap portion of mound It destroys minimum.As previously mentioned, providing deep pool opening to accelerate for being fluidly connected to the room with vacuum pump in convolution Ensure enough vacuum levels in the room in device use process.However, according to the present invention, giving deep pool opening function further below Can: the magnetic field in valley point is controlled at the level of the outmost circulation of particle beam path 12 (referring to Fig. 5).For the original Cause, it is essential that deep pool opening paddy peripheral edge 4vp of 11 positions from each paddy is very close.Deep circumference is to paddy peripheral edge The distance Lap of 4vp be defined as along perpendicular to and by central axis Z deep longitudinal axis Lar deep pool opening 11 circumference with The shortest distance is measured between the paddy peripheral edge 4vp of corresponding paddy fan block.Deep circumference is defined as deep pool opening perpendicular to center The circumference in the section in the plane of axis and the lower distal end 3lde including adjacent side 3L.If bottom surface 4B is around deep pool It is plane in the region of opening, then deep circumference is only the antelabium of deep pool opening being formed between bottom surface and the opening.

The end at edge is defined as two limited the end for limiting the edge one of extremely.Proximal end is position The end nearest from central axis Z.Distal end is the position end farthest from central axis Z.End, which can be, is defined as two Or more the turning point of point that meets of line.Turning point can also be defined as curve near tangent reindexing or show not connecting The point of continuous property.

Edge is the line segment that two surfaces are met.Edge limits two as defined above using both ends as boundary The one side on each surface in the surface met.It is concentrated due to the limitation of machinery tools and in order to reduce stress, Two surfaces are often met with given radius of curvature R, this makes it difficult to definitely define the geometry that edge intersects with two surfaces Position.In this case, edge is defined as and two outer pushing surface phases being extrapolated for intersecting with each other with unlimited curvature (1/R) The geometrical line of friendship.Top edge is the edge intersected with the upper surface 3U of mound fan block, and lower edge is the bottom surface with paddy fan block The edge of 4B intersection.

What peripheral edge was defined as surface includes the edge of the position point farthest from central axis Z.If farthest point is The shared turning point in two edges, then peripheral edge or surface, the distance center axis Z maximum edge of average distance. For example, upper peripheral edge is the edge of the point farthest from central axis including position of upper surface.If mound fan block is compared to one Fruits cake, peripheral edge by be Fruit cake peripheral crust.

In a similar way, what center edge was defined as surface includes the edge of the position point nearest from central axis Z. For example, upper center edge is the edge of the point nearest from central axis Z including position of upper surface.

Side edge is defined as the proximal end of center edge being linked to the edge of the distal end of peripheral edge.The proximal end of side edge Therefore be the side edge the end intersected with center edge, and the distal end of the side edge be the side edge with it is outer The end of peripheral edge intersection.

Depending on the design of cyclotron, upper center edge/lower center edge can have different geometries.Most Common geometry be relative to central axis Z have finite length (≠ 0) often circular concave, the concave with Proximal end/lower proximal end is boundary on separated from each other first and second.The particle beams is introduced gap conceding space by this configuration When be useful.Under the first alternative configuration, the first and second center proximal ends are merged into single center near point, thus on being formed The vertex of surface 3U, the vertex only include three edges, and center edge has zero-length.If mound fan block is compared to one again Fruits cake, then the tip of this part will be corresponding with the center edge for being so reduced to a single point.In the second alternative configuration Under, the transitional face from first side edge to second side edge can be bending convex surface for central axis Z, appoint to be produced without The smooth transition of what turning point.Under this configuration, center edge also reduces into a single point, and a single point is defined as tangent line The point of reindexing.In general, mound fan block does not also extend to central axis even under the first and second alternative configurations Line concedes the region for directly surrounding central axis to allow to be inserted into the particle beams.

Preferably, as shown in Figure 3, the first and second side surface 3L are bevelings, thus respectively on first and second Side edge forms scarf.Scarf is defined as by cutting away via there is no the edges that two surfaces of scarf are formed And obtain the intermediate surface between two surfaces.Scarf reduces the angle of the formation of edge between two surfaces.Beveling Face is often used in mechanical devices to concentrate for reducing stress.However, in cyclotron, in the upper surface of mound fan block Horizontal beveling side surface enhance the focusing of the particle beams when the particle beams reaches mound gap portion 7h.

As shown in Figure 3, the peripheral surface 3P of mound fan block can also form scarf at upper peripheral edge, with an improved Magnetic field's regularity near peripheral edge.

Cyclotron according to the present invention preferably includes N=3 to 8 mound fan block 3.It is highly preferred that such as the institute in figure It shows, N=4.For the even number value of N, mound fan block 3 and paddy fan block 4 have to be around central axis according to any symmetry of 2n It is distributed, wherein n=1 to N/2.Preferably, n=N/2, so that all N number of mound fan blocks are identical from one another, and all N number of paddy It is identical from one another to fan block.For the odd number value of N, mound fan block 3 and paddy fan block 4 have to be around central axis according to any right of N The distribution of title property.In a preferred embodiment, for all N=3-8 (i.e. according to the symmetry of N), N number of mound fan block 3 surrounds central axis Line is uniformly distributed.First and second magnetic poles 2 be oriented their corresponding upper surface 3U facing each other and about with it is coaxial The mesion MP that the respective central axes Z of first and second magnetic poles 2 is vertical is symmetrical.

The shape of block is fanned on mound and a Fruit cake (often as previously discussed, without tip) is equally often Wedge shape, wherein the first and second side surface 3L (usually not get at the central axis from peripheral surface towards central axis Z convergence Line).Mound azimuth angle alpha h and side surface (extrapolation) upper edge, at central axis Z or crosspoint adjacent thereto The convergent angle that level measures is corresponding.Mound azimuth angle alpha h is preferably incorporated between 360 °/2N ± 10 °, more preferably 360 °/ Between 2N ± 5 °, most preferably between 360 °/2N ± 2 °.

It is preferably incorporated between 360 °/2N ± 10 °, more preferably in the paddy azimuth angle alpha v that the level of central axis Z measures Ground is between 360 °/2N ± 5 °, most preferably between 360 °/2N ± 2 °.Paddy azimuth angle alpha v can be equal to mound azimuth angle alpha h.? In the case of the symmetry of N, α v=360/N- α h, for example, α v is the complementary angle of α h, wherein α v=90 °-α h for N=4.

It is necessary that maximum distance Lh between central axis and peripheral edge is heavily dependent on the particle before extraction The intensity of the target energy and magnetic field that reach.For example, maximum distance Lh is less than 750mm in 18MeV bevatron, Typically 520mm to 550mm.Upper peripheral edge has the azimuth Ah measured between outer peripheral end on first and second, and And it can be close in Ah=Lh × α h [rad].

Magnetic field is generated in the gap that two magnetic poles and the electromagnetic coil 14 being wrapped on each magnetic pole are formed between magnetic pole (electricity) magnet, the spiral path 12 of central area that the magnetic field is shown along Figure 4 and 5, originating in cyclotron It guides and focuses charged particle beam (=the particle beams), until it reaches the target energy of such as 18MeV.As previously discussed, Magnetic pole is often divided into alternate mound fan block and paddy fan block around central axis Z distribution.As used in Fig. 5 indicated by block arrow, Therefore high-intensity magnetic field B is created in the mound gap portion 7h with average height Gh in the fan block of mound, and with thinner arrow in such as Fig. 5 Weaker magnetic field is created in the paddy gap portion 7v with height Gv > Gh in paddy fan block indicated by head, to create grain The vertical focusing of beamlet.The magnetic field ratio in the deep gap portion 7a of the height Ga having > > Gv > Gh between two deep pool openings 11 It is weaker in paddy gap portion 7v.

When the particle beams is introduced into cyclotron, (do not show by the so-called d font electrode being located in paddy fan block The electric field created makes to state institute's particle beam acceleration out), and in paddy fan block, magnetic field is weaker.Accelerated particle penetrates mound gap every time (magnetic field in the mound gap portion is stronger due to the higher speed compared with previous mound gap portion), quilt in the 7h of part The Magnetic field shifts and form radius ratio substantially circular orbital path bigger in previous mound gap portion.Once particle Beam has accelerated to its target energy, then draws the electron beam, such as Fig. 4 from cyclotron in the referred to as point of leading point PE Shown in.For example, can be by the way that H will be accelerated^-Ion beam is driven through the removing being made of the thin graphite flake positioned at leading point PE Device draws accelerating proton H⁺.By the H of stripper^-Ion loses two electronics and becomes positive H⁺.By changing particle charging Symbol, the curvature changes sign in its path in magnetic field, and therefore draw the particle beams towards target from cyclotron and (do not show Out).The type and details of other extraction systems and used extraction system known to those skilled in the art are for this hair It is not essential for bright.In general, leading point is located in the gap portion 7h of mound.Cyclotron can in same mound part To include several leading points.Because of the symmetry requirement of cyclotron, having more than one mound fan block includes leading point.For N Symmetry, all N number of mounds fan blocks include equal number of leading point.Leading point can be used separately or can simultaneously two Two ground use.

The weight and size of cyclotron according to the present invention have been reduced by optimizing multiple sizes.However, this Invention is characterized by so that deep pool opening 11 is displaced outwardly the paddy peripheral edge 4vp close to paddy fan block, to reduce in magnetic pole Paddy fans the intensity in the magnetic field at the periphery of block, and magnetic field described herein is normally more stronger than closer to central axis Z, and less It is even.Specifically, the distance of deep pool opening 11 to paddy peripheral edge 4vp can be summarized as what edge intersected vertically with central axis Z with feature The shortest distance Lap that deep longitudinal axis Lar is measured between the periphery or antelabium and paddy peripheral edge 4vp of deep pool opening 11.According to The value of shortest distance Lap in cyclotron of the invention is typically less than 50mm, is preferably less than 30mm, is more preferably small In 20mm.It should not be from peripheral edge too closely so as not to the singular point in the creation magnetic field at the paddy peripheral edge being difficult to control accurately. It is therefore preferred to be at least 1mm, preferably at least 5mm for the value of Lap.

The low value of shortest distance Lap of the deep opening to paddy peripheral edge is greatly lowered at peripheral place and fans from towards paddy The intensity in the magnetic field of magnetic pole outwardly in the orientation angular zone of block.Towards paddy fan block flux return yoke along deep longitudinal axis Lar Therefore the thickness Tv measured can be correspondingly reduced.According to the present invention, towards paddy fan block flux return yoke shortest distance Lap and Thickness Tv is selected such that the deep circumference of each paddy fan block returns yoke thickness Tv's multiplied by flux to the distance Lap of paddy peripheral edge Product and the peripheral edge that is measured along deep longitudinal axis Lar to central axis Z distance Lv square ratio (Lap × Tv)/Lv² Less than 5%, preferably less than 3%, even more preferably less than 2%, even more preferably less than 1%.By comparing, prior art 18MeV Cyclotron can have about 8% to 11% ratio (Lap × Tv)/Lv².Flux towards paddy fan block returns the thickness of yoke 6 The reduction of degree causes the significantly reduction of the weight and size of magnetic yoke.

Big deep pool opening 11 is also advantageous.Deep pool opening is usually with the circular cross-section of radius Ra.As defined above, if Lv is to measure distance along deep longitudinal axis Lar between central axis Z and paddy peripheral edge, then the diameter 2Ra that deep pool is open is preferably Including between the 45% of Lv value and 60%, preferably between 48% and 55%.In deep pool, opening is used only for creating indoors In the conventional cyclotron of vacuum, usually using about 40% or so small diameter.With central axis Z and deep opening section The distance between center La compare, 2Ra be preferably La value at least 60%, preferably at least 65%, more preferably extremely Few 70%.For the cyclotron of 18MeV, deep diameter 2Ra may include between 240mm and 300mm.

If deep pool opening section be not it is circular, use hydraulic radius R_hydRather than Ra, wherein R_hyd=4A/P, Middle A and P is the area and perimeter of deep opening section.

So that deep pool opening 11 is located close to paddy peripheral edge 4vp and also increases when the particle beams enters between mound from deep gap portion 7a Focusing effect of the magnetic field on particle beams when in the 7h of gap part.Can therefore it reduce between inferior border edge and side edge Mound height Hh, and in the particle beams of high order focusing, the height of mound gap portion can also be reduced.For example, mound gap The height ratio Gh/Gv of the average paddy clearance height Gv of partial average mound clearance height Gh and paddy gap portion (are equal to Gh/ (2Hh+Gh)) it may include between 8% and 20%.In conventional deep valley cyclotron, Gh/Gv ratio can not surpass substantially 5% is crossed, wherein the value of Hh is significantly higher.All these elements facilitate the size and weight for significantly reducing cyclotron.

The average mound clearance height Gh of the mound gap portion of cyclotron according to the present invention may include 20mm with Between 27mm, preferably between 22mm and 26mm.The average paddy clearance height Gv of paddy gap portion may include 100mm with Between 500mm, preferably between 150mm and 400mm, preferably between 200mm and 250mm.In low Gv value, return The total weight of rotation accelerator reduces, because on the one hand fan block in mound needs less material and on the other hand flux returns yoke with flat The row size small in the correspondence that central axis Z is measured.Compared with conventional sector-focused cyclotron, both Gh and Gv have There is low value.For example, height of the average mound clearance height Gh of mound gap portion multiplied by the average paddy clearance height Gv of paddy gap portion Spend product Gh × Gv and peripheral edge to central axis Z distance Lv square ratio (Gh × Gv)/Lv²Can less than 5%, it is excellent Selection of land is less than 3%, even more preferably less than 2%.In contrast, conventional sector-focused cyclotron can have about 6% and arrive 8% ratio (Gh × Gv)/Lv²。

Because there is the deep pool opening 11 close to paddy peripheral edge, along deep longitudinal axis Lar (that is, fanning block towards paddy Part at) flux that measures returns the thickness Tv of yoke and can reduce, although the bottom surface 4B of two opposite paddy fan blocks separate it is low Gv value.When it is contemplated that having separated the peripheral place of two magnetic poles of short distance Gv has high-intensity magnetic field, it is therefore desirable to when thick flux returns yoke, Low-intensity magnetic field only is created in cyclotron according to the present invention, because deep aperture position is so close from paddy peripheral edge. For example, average paddy clearance height Gv returns product Gv × Tv of yoke thickness Tv at a distance from peripheral edge to central axis Z multiplied by flux Lv square ratio (Gv × Tv)/Lv²It can be less than 20%, preferably less than 15%, even more preferably less than 10%.Existing skill Art sector-focused cyclotron Tongcheng has (Gv × Tv)/Lv2 ratio greater than 40%, even about 50%.

As shown in the figure, in a preferred embodiment, the first and second of paddy peripheral edge 4vp the lower distal end 3lde and central axis Line is Z-shaped at paddy azimuth angle alpha v, as previously discussed, fans block, the paddy azimuth and Qiu Fangwei for N=4 mound fan block and paddy Angle α h is complementary.For example, for N=4, paddy azimuth angle alpha v may include between 35 ° and 50 °, preferably between 40 ° and 46 °, More preferably between 42 ° and 45 °, and correspondingly, mound azimuth angle alpha h may include between 55 ° and 40 °, preferably exist Between 50 ° and 44 °, more preferably between 48 ° and 45 °.By increasing paddy azimuth angle alpha v, therefore it can reduce mound azimuth angle alpha h And correspondingly reduce the weight of cyclotron.As previously discussed, due to the high order focusing effect of deep pool opening 11, mound gap Part can have low mound gap portion height Gh value.The combination of large space between muscles azimuth angle alpha v and low Gh value can be summarized as not by feature Greater than the ratio Gh/tan (α v) of 30mm, preferably not more than 27mm.In prior art sector-focused cyclotron, ratio Gh/tan (α v) is usually higher and can be about between 40mm and 50mm.

As shown in Fig. 1 (b), the cyclotron of block is being fanned including N=4 or 8 mound fan block, preferably N=4 mound In preferred embodiment, flux goes back to inner surface and the outer surface of yoke 6 including faced chamber, the outer surface away from the room and with The inner surface is separated with the wall thickness that the flux returns yoke.The section perpendicular to central axis Z of inner surface has and central axis Line Z concentric circular geometry, and the section perpendicular to central axis Z of outer surface have be inscribed in and central axis Z Geometry in concentric square.The edge-perpendicular of square is in the deep longitudinal axis Lar of four paddy fan blocks.The geometric form Shape generates minimum flux in the part towards four paddy fan blocks that flux returns yoke and returns yoke thickness Tv.Preferably cut away turning for square Angle with equipment needed for being contained in the horizontal opening cyclotron of mesion MP (for example, hydraulic, electronic or pneumatic), and Therefore the external dimensions of cyclotron is further decreased.

By the geometry that is discussed before having, compared with downfield impart possibility by fanning to generate outside block towards paddy Magnetic yoke, so that it may produce size and weight significantly smaller cyclotron.For example, having produced according to the present invention The compact cyclotron of 18MeV, the similar 18MeV cyclotron that weight ratio generates before are small by about 1/3.The compact Cyclotron, which can be encapsulated in, has cooperation in the crate of standard multimodal transport container, this is returned for what is generated before It is impossible for revolving accelerator, so that transportation cost and difficulty be greatly lowered.

In order to which more cost-effectively production generates the cyclotron of more evenly characteristic, substrate 5, magnetic pole 2 and flux Yoke 6 is returned preferably all to be made of identical material.They are preferably all from the multiple element of single steel billet or single steel billet Machined (being produced that is, being operated by single continuously casting).At least multiple portions that substrate 5 and flux return yoke 6 are preferred Ground has the identical height measured along central axis Z.

The upper surface 3U of mound fan block is preferably lower than the upper surface that corresponding flux goes back to yoke part, offsets by distance Gh/2. If magnetic pole 2 is shelved on planar substrates 5, the height that the height of magnetic pole should be equal to corresponding flux go back to yoke part subtracts Gh/ 2.However, sometimes, the central axis perpendicular to the first and second substrates, the inner surface towards the room include for accommodating first With the recess of the second magnetic pole.In this case, the recess is deeper unlike Gh/2, so that returning yoke using with flux Mutually level magnetic pole and thus its upper surface is made to can achieve required level.

In order to further facilitate the installation and reproducibility of cyclotron, each of first and second magnetic poles can be with It is made of single integral member, including being machined integrally into all mounds come fan block and paddy fan block from described.This has the advantage that It is: can accurately controls relative position and the height of mound fan block and paddy fan block in a digital manner in machining process, rather than The final position at them on counterpart substrate is manuallyd locate dependent on by each mound fan block.

Cyclotron according to the present invention is more more compact than conventional cyclotron and lighter.By multinomial optimization make this at To be possible, but the method is characterized in that reduced by the way that deep pool opening is located very close to paddy peripheral edge 4vp from valley point The magnetic field generated outwardly.Initial design be only be make the room and deep pool opening 11 that vacuum pump is in fluid communication have herein it is following Further function: on the one hand, the particle beams more strong-focusing is made when the particle beams penetrates mound gap portion 7h, and on the other hand Significantly reduce the intensity from the magnetic field that paddy fan block generates outwardly.The two effects allow:

Reduce the thickness Tv that yoke is returned along the flux towards paddy fan block that deep longitudinal axis Lar is measured, to allow magnetic yoke Polygonal exterior surface, as Fig. 1 (b) is shown；

Reduce mound gap portion height Gh, this height for causing flux to return yoke reduces；

Reduce mound and fan block height Hh, this height for also causing flux to return yoke reduces.

All these elements both contribute to the size and weight for significantly reducing cyclotron.It has been given in this specification The example of the prior art He 18MeV energy cyclotron of the present invention is gone out.It should be clear that identical principle is suitable for reducing difference The size and weight of the cyclotron of energy.

Claims

1. a kind of for making the particle beams include the cyclotron accelerated on given path in gap, the convolution accelerates Device includes:

(a) it is limited to the room in magnetic yoke, wherein the magnetic yoke is by going back to yoke (6) perpendicular to central axis Z and each other by flux First substrate and the second substrate (5) formation separated, the flux return the lateral outer wall that yoke limits the cyclotron,

(b) the first magnetic pole and the second magnetic pole (2), first magnetic pole and second magnetic pole are located at the interior and about vertical Relative to each other, and the be separated from each other gap (7), and its are directly symmetrically positioned into the mesion of the central axis Z In, each of first magnetic pole and second magnetic pole include,

(c) at least three mound fan block (3) with upper surface (3U) and equal number of paddy including bottom surface (4B) fan block (4), The mound fan block and paddy fan block are alternately distributed around the central axis Z, so that by first magnetic pole and institute Stating the gap that the second magnetic pole separates includes mound gap portion (7h) and paddy gap portion (7v), the mound gap portion quilt It is limited between the upper surface of two opposite mound fan blocks and there is the average mound clearance height measured along the central axis Z Gh, the paddy gap portion are limited between the bottom surface of two opposite paddy fan blocks and have and survey along the central axis Z Average paddy clearance height Gv, wherein Gv > Gh；

(d) bottom surface (4B) of each paddy fan block is limited by paddy peripheral edge (4vp), and the paddy peripheral edge is under first Distal end and the second lower distal end (3lde) are boundary, and be defined as the bottom surface, position it is farthest from the central axis Z Edge；

(e) bottom surface (4B) of each paddy fan block further comprises deep opening, and the deep pool opening extends through the magnetic yoke The first substrate and the second substrate thickness and limit height and be Ga, be at least five times of Gh big deep clearance portions Point, the deep pool opening has perpendicular to the central axis Z, the section limited by deep circumference, outside the deep pool circumference and the paddy Peripheral edge is separated along the shortest distance Lap measured with the deep longitudinal axis Lar that the central axis Z intersects vertically, and its In, the paddy peripheral edge separates with the central axis Z and measures distance Lv along the deep pool longitudinal axis Lar；

(f) flux, which goes back to yoke (6), has the wall thickness Tv changed with the Angle Position around the central axis Z, has edge The minimum wall thickness value that the deep longitudinal axis Lar of each paddy fan block is measured；It is characterized in that, the deep circumference of each paddy fan block arrives The distance Lap of the paddy peripheral edge returns the product and the paddy peripheral edge to the center of the wall thickness Tv of yoke multiplied by the flux The distance Lv of axis Z square ratio (Lap × Tv)/Lv²Less than 5%.

2. cyclotron according to claim 1, wherein the deep circumference of each paddy fan block to the paddy periphery sides The distance Lap of edge is multiplied by the product of the wall thickness Tv of the flux time yoke at a distance from the paddy peripheral edge to the central axis Z Lv square ratio (Lap × Tv)/Lv²Less than 3% or less than 2% or less than 1%.

3. cyclotron according to claim 1, wherein the diameter 2Ra of the deep pool opening with along the deep radial axle The ratio 2Ra/Lv packet for the distance Lv for separating the paddy peripheral edge (4vp) and the central axis Z that line Lar is measured It includes between 45% and 60% or between 48% and 55%.

4. cyclotron according to claim 2, wherein the diameter 2Ra of the deep pool opening with along the deep radial axle The ratio 2Ra/Lv packet for the distance Lv for separating the paddy peripheral edge (4vp) and the central axis Z that line Lar is measured It includes between 45% and 60% or between 48% and 55%.

5. cyclotron described in any one of -4 according to claim 1, wherein it is described deep pool opening diameter 2Ra with it is described The ratio 2Ra/La of the distance between the center of central axis Z and deep opening section La be La value at least 60% or at least 65% or at least 70%, and wherein, the diameter 2Ra of the deep pool opening is included between 240mm and 300mm.

6. cyclotron described in any one of -4 according to claim 1, wherein the average paddy clearance height Gv is multiplied by institute State flux return yoke wall thickness Tv product Gv × Tv and the paddy peripheral edge to the central axis Z distance Lv square ratio Rate (Gv × Tv)/Lv²Less than 20% or less than 15% or less than 10%.

7. cyclotron according to claim 5, wherein the average paddy clearance height Gv returns yoke multiplied by the flux Wall thickness Tv product Gv × Tv and the paddy peripheral edge to the central axis Z distance Lv square ratio (Gv × Tv)/Lv²Less than 20% or less than 15% or less than 10%.

8. cyclotron described in any one of -4 and 7 according to claim 1, wherein the described of the mound gap portion is put down The height ratio Gh/Gv of the average paddy clearance height Gv of equal mound clearance height Gh and the paddy gap portion is included in 8% Between 20%.

9. cyclotron according to claim 5, wherein the average mound clearance height Gh of the mound gap portion It is included between 8% and 20% with the height ratio Gh/Gv of the average paddy clearance height Gv of the paddy gap portion.

10. cyclotron according to claim 6, wherein the average mound clearance height of the mound gap portion The height ratio Gh/Gv of the average paddy clearance height Gv of Gh and the paddy gap portion is included between 8% and 20%.

11. cyclotron described in any one of -4,7 and 9-10 according to claim 1, wherein the mound gap portion Height product and the paddy of the average mound clearance height Gh multiplied by the average paddy clearance height Gv of the paddy gap portion Peripheral edge to the central axis Z distance Lv square ratio (Gh × Gv)/Lv²It is less than 5% or less than 3% or small In 2%.

12. cyclotron according to claim 5, wherein the average mound clearance height of the mound gap portion Gh is accumulated and the paddy peripheral edge to the center multiplied by the height of the paddy clearance height Gv that is averaged of the paddy gap portion The distance Lv of axis Z square ratio (Gh × Gv)/Lv²Less than 5% or less than 3% or less than 2%.

13. cyclotron according to claim 6, wherein the average mound clearance height of the mound gap portion Gh is accumulated and the paddy peripheral edge to the center multiplied by the height of the paddy clearance height Gv that is averaged of the paddy gap portion The distance Lv of axis Z square ratio (Gh × Gv)/Lv²Less than 5% or less than 3% or less than 2%.

14. cyclotron according to claim 8, wherein the average mound clearance height of the mound gap portion Gh is accumulated and the paddy peripheral edge to the center multiplied by the height of the paddy clearance height Gv that is averaged of the paddy gap portion The distance Lv of axis Z square ratio (Gh × Gv)/Lv²Less than 5% or less than 3% or less than 2%.

15. according to claim 1-4,7, cyclotron described in any one of 9-10 and 12-14, wherein the mound gap The partial average mound clearance height Gh is included between 20mm and 27mm or between 22mm and 26mm.

16. cyclotron according to claim 5, wherein the average mound clearance height of the mound gap portion Gh is included between 20mm and 27mm or between 22mm and 26mm.

17. cyclotron according to claim 6, wherein the average mound clearance height of the mound gap portion Gh is included between 20mm and 27mm or between 22mm and 26mm.

18. cyclotron according to claim 8, wherein the average mound clearance height of the mound gap portion Gh is included between 20mm and 27mm or between 22mm and 26mm.

19. cyclotron according to claim 11, wherein the average mound clearance height of the mound gap portion Gh is included between 20mm and 27mm or between 22mm and 26mm.

20. according to claim 1-4,7, cyclotron described in any one of 9-10,12-14 and 16-19, wherein described The average paddy clearance height Gv of paddy gap portion be included between 100mm and 500mm or between 150mm and 400mm, Or between 200mm and 250mm.

21. cyclotron according to claim 5, wherein the average paddy clearance height of the paddy gap portion Gv is included between 100mm and 500mm or between 150mm and 400mm or between 200mm and 250mm.

22. cyclotron according to claim 6, wherein the average paddy clearance height of the paddy gap portion Gv is included between 100mm and 500mm or between 150mm and 400mm or between 200mm and 250mm.

23. cyclotron according to claim 8, wherein the average paddy clearance height of the paddy gap portion Gv is included between 100mm and 500mm or between 150mm and 400mm or between 200mm and 250mm.

24. cyclotron according to claim 11, wherein the average paddy clearance height of the paddy gap portion Gv is included between 100mm and 500mm or between 150mm and 400mm or between 200mm and 250mm.

25. cyclotron according to claim 15, wherein the average paddy clearance height of the paddy gap portion Gv is included between 100mm and 500mm or between 150mm and 400mm or between 200mm and 250mm.

26. according to claim 1-4,7, cyclotron described in any one of 9-10,12-14,16-19 and 21-25, In, the lower distal end of described the first of the paddy peripheral edge (4vp) and second lower distally (3lde) and the central axis are Z-shaped At paddy azimuth angle alpha v, so that the ratio of average the mound clearance height Gh and the azimuthal tangent value tan (α v) of the paddy Gh/tan (α v) is no more than 30mm or is not more than 27mm.

27. cyclotron according to claim 5, wherein the lower distal end of described the first of the paddy peripheral edge (4vp) It is Z-shaped at paddy azimuth angle alpha v with the described second lower distal end (3lde) and the central axis, so that the average mound gap is high The ratio Gh/tan (α v) of Gh and the azimuthal tangent value tan (α v) of the paddy is spent no more than 30mm or is not more than 27mm.

28. cyclotron according to claim 6, wherein the lower distal end of described the first of the paddy peripheral edge (4vp) It is Z-shaped at paddy azimuth angle alpha v with the described second lower distal end (3lde) and the central axis, so that the average mound gap is high The ratio Gh/tan (α v) of Gh and the azimuthal tangent value tan (α v) of the paddy is spent no more than 30mm or is not more than 27mm.

29. cyclotron according to claim 8, wherein the lower distal end of described the first of the paddy peripheral edge (4vp) It is Z-shaped at paddy azimuth angle alpha v with the described second lower distal end (3lde) and the central axis, so that the average mound gap is high The ratio Gh/tan (α v) of Gh and the azimuthal tangent value tan (α v) of the paddy is spent no more than 30mm or is not more than 27mm.

30. cyclotron according to claim 11, wherein described the first of the paddy peripheral edge (4vp) is lower remote End and the second lower distal end (3lde) and the central axis are Z-shaped at paddy azimuth angle alpha v, so that the average mound gap The height Gh and ratio Gh/tan (α v) of the azimuthal tangent value tan (α v) of the paddy is no more than 30mm or is not more than 27mm.

31. cyclotron according to claim 15, wherein described the first of the paddy peripheral edge (4vp) is lower remote End and the second lower distal end (3lde) and the central axis are Z-shaped at paddy azimuth angle alpha v, so that the average mound gap The height Gh and ratio Gh/tan (α v) of the azimuthal tangent value tan (α v) of the paddy is no more than 30mm or is not more than 27mm.

32. cyclotron according to claim 20, wherein described the first of the paddy peripheral edge (4vp) is lower remote End and the second lower distal end (3lde) and the central axis are Z-shaped at paddy azimuth angle alpha v, so that the average mound gap The height Gh and ratio Gh/tan (α v) of the azimuthal tangent value tan (α v) of the paddy is no more than 30mm or is not more than 27mm.

33. cyclotron according to claim 26, wherein the paddy azimuth angle alpha v is greater than 35 ° and is also no more than 50 ° or the paddy azimuth angle alpha v are greater than 35 ° and are also no more than 46 ° or the paddy azimuth angle alpha v greater than 35 ° and do not surpass also Cross 45 °.

34. the cyclotron according to any one of claim 27-32, wherein the paddy azimuth angle alpha v is greater than 35 ° simultaneously And also it is no more than 50 ° or the paddy azimuth angle alpha v and is greater than 35 ° and is also no more than 46 ° or the paddy azimuth angle alpha v greater than 35 ° And also it is no more than 45 °.

35. cyclotron according to claim 26, wherein the paddy azimuth angle alpha v is greater than 40 ° and is also no more than 50 ° or the paddy azimuth angle alpha v are greater than 40 ° and are also no more than 46 ° or the paddy azimuth angle alpha v greater than 40 ° and do not surpass also Cross 45 °.

36. the cyclotron according to any one of claim 27-32, wherein the paddy azimuth angle alpha v is greater than 40 ° simultaneously And also it is no more than 50 ° or the paddy azimuth angle alpha v and is greater than 40 ° and is also no more than 46 ° or the paddy azimuth angle alpha v greater than 40 ° And also it is no more than 45 °.

37. cyclotron according to claim 26, wherein the paddy azimuth angle alpha v is greater than 42 ° and is also no more than 50 ° or the paddy azimuth angle alpha v are greater than 42 ° and are also no more than 46 ° or the paddy azimuth angle alpha v greater than 42 ° and do not surpass also Cross 45 °.

38. the cyclotron according to any one of claim 27-32, wherein the paddy azimuth angle alpha v is greater than 42 ° simultaneously And also it is no more than 50 ° or the paddy azimuth angle alpha v and is greater than 42 ° and is also no more than 46 ° or the paddy azimuth angle alpha v greater than 42 ° And also it is no more than 45 °.

39. according to claim 1-4,7, being returned described in any one of 9-10,12-14,16-19,21-25,27-33,35 and 37 Revolve accelerator, including N=4 or 8 mound fan block (3) and equal number of paddy fan block (4), wherein the flux goes back to yoke (6) and includes Inner surface towards the room and away from the outer surface of the room, and the outer surface and the inner surface separate it is described logical The wall thickness of yoke is measured back, and wherein, the section perpendicular to the central axis Z of the inner surface has and the central axis Z concentric circular geometry, and wherein the section perpendicular to the central axis Z of the outer surface have be inscribed in Geometry in the central axis Z concentric square, the edge-perpendicular of the square is in the deep diameter of four paddy fan blocks To axis Lar.

40. cyclotron according to claim 39, wherein the turning of the square is cut off.

41. according to claim 1-4,7, described in any one of 9-10,12-14,16-19,21-25,27-33,35,37 and 40 Cyclotron, wherein the first substrate and the second substrate (5), first magnetic pole and second magnetic pole (2) and The flux goes back to yoke (6) and is all manufactured from the same material and the first substrate and the second substrate (5) and the flux The multiple portions for going back to yoke (6) have the identical height measured along the central axis Z.

42. according to claim 1-4,7, described in any one of 9-10,12-14,16-19,21-25,27-33,35,37 and 40 Cyclotron, wherein each magnetic pole in first magnetic pole and second magnetic pole is made of single integral member, thus Block is fanned including its all mound fan block and paddy.