CN109413832A - Magnetic mode shift pipe linear accelerator is indulged using the interdigital of permanent magnetism quadrupole electromagnet - Google Patents
Magnetic mode shift pipe linear accelerator is indulged using the interdigital of permanent magnetism quadrupole electromagnet Download PDFInfo
- Publication number
- CN109413832A CN109413832A CN201811272717.6A CN201811272717A CN109413832A CN 109413832 A CN109413832 A CN 109413832A CN 201811272717 A CN201811272717 A CN 201811272717A CN 109413832 A CN109413832 A CN 109413832A
- Authority
- CN
- China
- Prior art keywords
- drift tube
- drift
- permanent magnetism
- main body
- quadrupole electromagnet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H9/00—Linear accelerators
- H05H9/04—Standing-wave linear accelerators
- H05H9/041—Hadron LINACS
- H05H9/042—Drift tube LINACS
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Particle Accelerators (AREA)
Abstract
A kind of interdigital using permanent magnetism quadrupole electromagnet proposed by the present invention indulges magnetic mode shift pipe linear accelerator, belong to linear accelerator technical field, including the multiple drift tubes installed along vacuum radio frequency resonant cavity central axis, the linear accelerator is divided into longitudinal bunching section, 0 ° of accelerating sections, transverse focusing section along incoming particle beam direction of advance, and it is affixed to pass through the first support bar ridge structure different from vacuum radio frequency resonant cavity respectively for adjacent drift tube in longitudinal bunching section and 0 ° of accelerating sections；Drift tube in transverse focusing section is affixed by second support bar and ridge structure, and is axially arranged with three along the drift tube inside drift tube with focusing-diverging-focus version arrangement permanent magnetism quadrupole electromagnet, and the magnetic center of each magnet is overlapped with the machine center of drift tube.The present invention lateral radius of drift tube and all more existing KONUS draft tube linac of longitudinal length in transverse focusing section are substantially reduced, to improve the accelerating ability of accelerator.
Description
Technical field
The invention belongs to linear accelerator technical field, in particular to a kind of interdigital using permanent magnetism quadrupole electromagnet is vertical
Magnetic mode shift pipe linear accelerator.
Background technique
The structure of draft tube linac is that one kind is equipped at least two drift tube (drift tube on central axis
Main body be hollow cylindrical conductor) vacuum radio frequency resonant cavity, the vacuum radio frequency resonant cavity cavity up and down (or left and right)
Side is symmetrically arranged with a pair of of ridge structure, and each drift tube is fixed by support rod and cavity body structure.Its working principle is that: in resonant cavity
The high power RF of feed-in setpoint frequency, these radio frequencies can generate electric field between drift tube, and the hollow circle inside drift tube
Columnar region meeting shielded radio frequency, does not generate electric field.Charged particle beam group's (motion profile of particle beams group is known as " bunch ") is in
When region (region is referred to as " accelerating gap ") that mandrel line passes through between adjacent drift pipe, the electric field that generated by radio frequency is understood
Accelerate；When the electric field that the radio frequency of mechanical periodicity generates is in charged particle deceleration regime, it is located at drift tube inner hollow circle
The charged particle beam group of columnar region will not be decelerated；To make whole process be an accelerator.
Radio-frequency power in the resonant cavity of draft tube linac is typically in both of which: TM mode (electric field along
Electricity mould is indulged in bunch direction, also referred to as E mould) and TE mode (indulging magnetic mould along bunch direction, also referred to as H mould in magnetic field).Using TM mode
Draft tube linac be known as A Er Varese (Alveraz) type: radio-frequency power generates directly in resonant cavity along bunch
The electric field in direction, columnar support rod are used only for installation drift tube, therefore all in the same side, the drift tube of this structure adds
Fast device proposes that structure and processing technology are all more mature, and the beam intensity that can accelerate is also higher earliest.With proton
With the development of heavy particle therapy cancer technology, low beam intensity has also obtained very big hair using the drift tube accelerator of TE mode
Exhibition.Using TE mode draft tube linac there are mainly two types of: KONUS (Kombinierte Null Grad
Strukture-combines 0 ° of accelerating structure) draft tube linac (Tiede R, Ratzinger U, Podlech H, et
al.KONUS beam dynamics designs using H-mode cavities[J].Hadron Beam,2008,1:
2013.) and APF (Alternating Phase Focusing, alternating phase focus)-IH (interdigital H mode,
It is interdigitated) draft tube linac (Iwata Y, Yamada S, Murakami T, et al.Alternating-phase-
focused IH-DTL for an injector of heavy-ion medical accelerators[J].Nuclear
Instruments and Methods in Physics Research Section A:Accelerators,
Spectrometers,Detectors and Associated Equipment,2006,569(3):685-696.)；TE mode
Draft tube linac in, radio-frequency power directly generate along bunch direction electric field (magnetic field is along bunch direction), but
Generate opposite voltage on two opposite ridge structures and its connected support rod, drift tube alternately with two ridge structure phases
Even, there are voltage differences between two adjacent drift tubes, form accelerating field.
Compared to the A Er Varese type drift tube accelerator (shunting impedance < 50M Ω/m) of TM mode, the drift of TE mode
Pipe accelerator has higher shunting impedance (being greater than hundred M Ω/m), and under identical acceleration request, required radio-frequency power is far low
Yu Aer Varese type drift tube accelerator.In existing draft tube linac, charged particle is in a RF (Radio
Frequency, radio frequency) accelerate in part-time in the period, hide retarding field within another part time, even if accelerator
Entrance is continuous line, and finally obtain acceleration also can only be the charged particle beam group with certain longitudinal length.For electrification
Particle beams group, the Coulomb force between particle will lead to beam group at laterally (perpendicular to beam direction) and longitudinally (along beam direction)
Diverging.To solve the divergence problem, transverse focusing and longitudinal pack are needed.In longitudinal pack according to phase stability, choosing
Suitable accelerating phase (being typically chosen -30 ° or so) is selected to achieve that；Then need to introduce additional quadrupole magnetic in lateral focusing
Iron.Quadrupole electromagnet is installed in the requirement of A Er Varese type drift tube accelerator in drift tube, and (quadrupole electromagnet includes electric quadrupole magnet
With permanent magnetism quadrupole electromagnet, difficulty of processing and complexity ratio IH drift tube accelerator are much larger, and A Er Varese type is caused to float
The processing cost for moving pipe accelerator is much higher compared with IH drift tube accelerator.
Current KONUS draft tube linac and APF-IH draft tube linac is all using interdigitated structure
TE pattern drifting pipe accelerator, main difference is that in the design of focusing structure and beam dynamics.KONUS drift tube is straight
Accelerator cavity is divided into three parts by line accelerator from beam dynamics, by the acceleration of the particle beams, transverse focusing and longitudinal direction
Pack separates, and realizes different functions in different vacuum cavity regions.And APF is then using the peace by design drift tube
Holding position realizes the transverse focusing of the particle beams using the electromagnetic field inside vacuum cavity, is not needing additional magnet to be gathered
It is burnt.
KONUS draft tube linac three parts from being kinetically made of: longitudinal bunching section A, 0 ° of accelerating sections B and cross
To focusing section C.The structure of one typical KONUS draft tube linac is as shown in Figure 1.Wherein, in the area longitudinal bunching section A
Synchronous particle phase in domain is generally -35 ° or so, rolls into a ball using the field RF between accelerating gap to the particle beams and carries out longitudinal gather
Beam；The center of charged particle beam group in 0 ° of accelerating sections B area is variation relative to the phase of radio frequency, (general from the several years
Greater than 0 ° less than 10 °) start phase slip, terminate until ten several years；In the region transverse focusing section C, charged particle beam group warp
It crosses after longitudinal direction bunching section A and 0 ° of accelerating sections B, since the space-charge force of RF blooming effects and line itself influences,
The lateral envelope of line becomes larger, it is therefore desirable to flow into line focusing in lateral halved tie.Specifically, existing KONUS drift tube straight line adds
Fast device forms FDF (Focusing- in the electric quadrupole magnet 5 that transverse focusing section C is alternately placed using three
Defocusing-Focusing, focuses, and-defocusing-focuses) focusing structure of form, referring to Fig. 1 (in Fig. 1 in transverse focusing section C
Support rod do not illustrate), the cross section of transverse focusing section C is referring to fig. 2.In this drift tube accelerator, drift tube
Size is generally all smaller (diameter about 20mm), and 5 volume of electric quadrupole magnet is larger, causes in the region transverse focusing section C for pacifying
The lateral dimension (about 160mm) and longitudinal size (being greater than 200mm) of the drift tube 3 of electric discharge quadrupole electromagnet 5 are all larger.One side
Face, in order to guarantee the mounting stability of drift tube 3 in the region transverse focusing section C and reduce the risk struck sparks, except one shown in Fig. 2
It, need to also be in other direction extension supporting bars 6, for connecting drift tube 3 and vacuum radio frequency resonance outside to symmetrically arranged support rod 4
Chamber 1.On the other hand, the drift tube radius senior general of 0 ° of accelerating sections B of the drift tube radius ratio of transverse focusing section C and longitudinal bunching section A
The shunting impedance of drift tube accelerator is caused to decline, and the RF coupling between the vacuum cavity inside of drift tube accelerator
Can be more complicated, in order to solve the coupled problem, Normal practice is to cut symmetrically arranged ridge structure in the region transverse focusing section C
Fall part, but increases the working procedure of resonant cavity cavity with this；The longitudinal size of transverse focusing section C is larger, leads to band electrochondria
Beamlet group is in that accelerationless zone time is longer, declines the average acceleration gradient of entire resonant cavity.In addition, in transverse focusing
Section C setting electric quadrupole magnet 5 also needs to be passed through electric current and water cooling, so that the mechanical structure of cavity in this section is more complicated.
The electric field that APF-IH draft tube linac is formed using RF in accelerating gap charged particle is realized focus and
The effect for dissipating angle, by slowly changing the locking phase of particle, so that the RF focusing forces and debunching force to charged particle are handed over
For appearance, according to strong focusing principle, RF is to focus in lateral general effect to charged particle, is in longitudinal general effect
Pack, this ensure that charged particle beam group stablizes transmission and acceleration in the vacuum cavity of drift tube accelerator.Due to
RF not strong to the focusing force of charged particle, APF-IH draft tube linac cannot accelerate too high beam intensity (most at present
The big particle beams no more than 10mA).The outstanding feature of this draft tube linac is that portion is not placed for cross in the cavity
To the quadrupole electromagnet of focusing, there are some technical solutions that can consider to place some focusing in the front end or rear end that accelerate cavity at present
Electric quadrupole magnet (CN 103026802) is substantially by beam matching section (prime accelerator and the company for accelerating cavity
Socket part point) and cavity is accelerated to be combined, it improves into the quality of beam for accelerating cavity.
In addition to the draft tube linac of APF type, the drift tube with quadrupole electromagnet and support rod is that drift tube is straight
One of line accelerator important composition component.As previously mentioned, in the drift tube of current drift tube accelerator, quadrupole electromagnet point
For two types: electric quadrupole magnet and permanent magnetism quadrupole electromagnet.The processing and preparation method phase of drift tube containing electric quadrupole magnet
To simple, electric quadrupole magnet can be encapsulated in drift tube using this common process of electron beam welding.And contain permanent magnetism four
In the process of the drift tube of pole magnet, since electron beam welding will receive the interference in the magnetic field of permanent magnetism quadrupole electromagnet, influence
Welding effect needs to be processed using special process.In addition, this drift tube structure with quadrupole electromagnet and support rod,
All in the end of support rod, drift tube is suspended on by support rod to be accelerated in cavity its mounting surface, and is sealed forever in drift tube
The installation accuracy requirement at magnetic quadrupole electromagnet center is very high, results in the difficulty of processing pole of the drift tube with magnet and support rod
Greatly.
The component parts of the existing drift tube assemblies with permanent magnetism quadrupole electromagnet and support rod has: support rod, by dividing water
The drift tube chilled(cooling) water return (CWR) that column (copper), water jacket (copper) and water pipe are constituted, drift tube main body, pipe end-cap of drifting about, by muti-piece permanent magnetism
The permanent magnetism quadrupole electromagnet that ferromagnetic block is formed.
In presently disclosed technical data, the preparation method of the drift tube containing permanent magnetism quadrupole electromagnet and support rod has two
Kind: the first, after permanent magnetism quadrupole electromagnet is mounted in drift tube, drifted about using the electron beam welding with magnetic shielding device
Pipe and end cap, form a drift tube assemblies；The characteristics of this processing method is to use magnetic shielding device, for shielding permanent magnetism
Influence of the magnetic field of iron to electronic beam current guarantees the degree of reliability of welding；But due to using magnetic shielding device, so that electron beam welding
The process connect is more complicated and the magnetic screen tooling that needs processing and installation additional.Second, by the way of expanding with heat and contract with cold into
The installation of row permanent magnetism quadrupole electromagnet is broadly divided into two components, the drift with support rod using the drift tube of this processing method
Pipe housing and the drift tube inner sleeve with permanent magnetism quadrupole electromagnet are moved, by drift tube inner sleeve as low temperature environment (in liquid nitrogen), housing
It is placed in room temperature or warm water, due to expanding with heat and contract with cold, so that drift tube inner sleeve and the size of drift tube housing are just coincide, installation
Drift tube assemblies are placed in room temperature after the completion, and the inner sleeve and housing of drift tube can be because temperature change be expanded with heat and contract with cold, from each other
It is stuck, the drift tube assemblies being fastenedly connected are formed, due to the uncontrollability that component deforms in process of expansion and contraction, lead to its peace
The installation accuracy that precision is lower than the prior art is filled, and is related to low temperature in processing, the preservation of the component for cooperation is number
Tired, complex process is difficult.
In addition, in the process of the existing drift tube with permanent magnetism quadrupole electromagnet and support rod, the installation of drift tube
In support boom end, drift tube is suspended on by support rod to be accelerated in cavity in face, and the magnetic blow out centre sealed in drift tube
Installation accuracy requirement is very high, therefore it is required that the support rod in mounting surface position will have high rigidity, (otherwise support rod is being installed
The deformation of process is too big, and magnetic blow out centre deviates too big), and a part of support rod is in the vacuum for accelerating cavity, accelerator
On require this part to have fabulous electric conductivity.There are two types of solutions in the prior art: one is entire support rods to adopt
With steel part, oxygen-free copper is plated on support rod surface, the disadvantage is that heating conduction is very poor；Another kind is in acceleration inside cavity
Support rod uses anaerobic Copper fabrication, and other support rods are processed using stainless steel material, and the two is welded together to form one
Complete support rod, then welds together support rod and drift tube, and how to reduce support rod and drift in the welding process
(welding deformation amount exceeds a certain range to the deflection of shifting pipe, can lead to drift tube hub and design value deviation is too big, Wu Faxiu
Just, entire workpiece cancels) it is difficult to implement.
Summary of the invention
The purpose of the invention is to overcome the shortcoming of prior art, a kind of friendship using permanent magnetism quadrupole electromagnet is provided
Interdigitation indulges magnetic mode shift pipe linear accelerator.The present invention passes through the transverse focusing to existing KONUS draft tube linac
The improvement of section simplifies its mechanical structure, to improve the accelerating ability for accelerating cavity.
In order to achieve the above-mentioned object of the invention, it adopts the following technical scheme that
A kind of interdigital using permanent magnetism quadrupole electromagnet proposed by the present invention indulges magnetic mode shift pipe linear accelerator, including
Along multiple drift tubes of vacuum radio frequency resonant cavity central axis installation, in the upper and lower or left and right sides of the vacuum radio frequency resonant cavity cavity
It is symmetrically arranged with a pair of of ridge structure；The linear accelerator is divided into longitudinal bunching section A, 0 ° of accelerating sections along incoming particle beam direction of advance
B, in transverse focusing section C, the longitudinal direction bunching section A and 0 ° of accelerating sections B adjacent drift tube pass through respectively first support bar with not
The same ridge structure is affixed；It is characterized in that, the drift tube in the transverse focusing section C passes through second support bar and the ridge
Structure is affixed, and is axially arranged with three along the drift tube inside the drift tube of the transverse focusing section C with focusing-diverging-focusing
The permanent magnetism quadrupole electromagnet of form arrangement, the magnetic center of each permanent magnetism quadrupole electromagnet are overlapped with the machine center of drift tube.
Further, in transverse focusing section C, the drift tube includes drift tube main body and drift pipe end-cap, described in three
It is arranged with focusing-diverging-focus version arrangement permanent magnetism quadrupole electromagnet in the drift tube body interior；In the drift tube master
It is equipped with cyclic water jacket between body and permanent magnetism quadrupole electromagnet, circumferentially uniformly distributed recirculated water is opened up on the lateral wall of the cyclic water jacket
Slot；The second support bar is hollow structure, passes sequentially through electron beam welding structure by stainless steel, the first bronze medal bar and the second bronze medal bar
At one end of the stainless steel is connect with the ridge structure screw, and the second bronze medal bar other end is embedded in the drift tube master
At the top of body or bottom, and the end is equipped with the through-hole being connected to circulating water chennel in the cyclic water jacket, the second bronze medal bar and drift
Pipe main body and cyclic water jacket joint are welded and fixed；In the drift tube main body and the welding process of support rod, pass through folder
Tool clamping one mills out technique head when carrying out roughing to drift tube main body to fix the drift tube main body, and the technique head
It is arranged on the drift tube main body lateral wall opposite with the support rod, after the completion of the drift tube main body and support rod welding
Milling removes the technique head.
Further, the drift pipe end-cap is to fix in the following manner with drift tube main body: first in the drift pipe end
The stitching portion of lid and drift tube main body carries out electron beam welding and forms the first weld seam, is then deviateing first weld seam or so each one
Electron beam welding is carried out at a beam spot beam radius distance again, and drifts about pipe end-cap in the welding process, between welding three times
Every progress to guarantee that drift tube body temperature is no more than the invalid temperature of the permanent magnetism quadrupole electromagnet.
The features of the present invention and beneficial effect are:
The present invention innovatively will use permanent magnetism using the transverse focusing section in conventional KONUS draft tube linac
Quadrupole electromagnet substitutes electric quadrupole magnet, so that under same magnetic field strength design requirement, KONUS draft tube linac
The lateral radius and longitudinal length of the drift tube of transverse focusing section all greatly reduce.The reduction of lateral radius improves accelerator
Shunting impedance reduces the difficulty of cavity RF design and tuning.The reduction of longitudinal length improves the average acceleration ladder of accelerator
Degree.Drift tube weight using the transverse focusing section of the KONUS draft tube linac of permanent magnetism quadrupole electromagnet is lighter, Ke Yizhi
It connects and is docked with ridge, and magnet no longer needs wire channel, simplify the design of mechanical structure.For this structure, the present invention
The manufacturing method for also innovatively improving the drift tube with permanent magnetism quadrupole electromagnet, by the way of electron beam welding three times come
Instead of existing magnetic screen formula electro-beam welding process, and in the slightly weak position of drift tube upper surface smoothness requirements reserved one
A technique head reduces deflection when welding between support rod component and drift tube body assembly, so that this have permanent magnetism
The drift tube of quadrupole electromagnet is able to real manufacture.
Detailed description of the invention
Fig. 1 is the schematic diagram of the section structure of the existing KONUS draft tube linac along axis；
Fig. 2 is the D-D schematic cross-section in Fig. 1；
Fig. 3 is that a kind of interdigital using permanent magnetism quadrupole electromagnet of the embodiment of the present invention indulges magnetic mode shift pipe linear accelerating
The schematic diagram of the section structure of the device along axis；
Fig. 4 is the D-D schematic cross-section in Fig. 3；
Fig. 5 (a), Fig. 5 (b) be respectively in the transverse focusing section C of the embodiment of the present invention drift tube along its axis and it is vertical its
Axial the schematic diagram of the section structure；
Fig. 6 is the structural schematic diagram of permanent magnetism quadrupole electromagnet in the embodiment of the present invention.
Specific embodiment
A kind of interdigital using permanent magnetism quadrupole electromagnet proposed by the present invention indulges magnetic mode shift pipe linear accelerator, is needle
To the improvement that existing KONUS draft tube linac proposes, detailed description are as follows with reference to the accompanying drawings and embodiments:
Referring to Fig. 3, Fig. 4, a kind of vertical magnetic mode shift Guan Zhi of the interdigital using permanent magnetism quadrupole electromagnet proposed by the present invention
Line accelerator, including the multiple drift tubes installed along 1 central axis of vacuum radio frequency resonant cavity, in the vacuum radio frequency resonant cavity cavity
(or left and right) side up and down be symmetrically arranged with a pair of of ridge structure 2；The linear accelerator is divided into vertical along incoming particle beam direction of advance
Into bunching section A, 0 ° of accelerating sections B, transverse focusing section C, longitudinal bunching section A and 0 ° of accelerating sections B, adjacent drift tube 3 passes through respectively
Support rod 4 and different ridge structures 2 are affixed；Drift tube 3 in transverse focusing section C is solid by second support bar 6 and ridge structure 2
It connects, and is axially arranged with three in the form of focusing-diverging-focusing (FDF) along the drift tube inside the drift tube 3 of transverse focusing section C
The magnetic center of the permanent magnetism quadrupole electromagnet 5 of arrangement, each permanent magnetism quadrupole electromagnet 5 is overlapped with the machine center of drift tube.
Referring to Fig. 5 (a), 5 (b), respectively transverse focusing section C is interior along linac axis and perpendicular to linear accelerator
The cross-sectional view of axis direction, in transverse focusing section C, drift tube 3 includes drift tube main body 31, drift pipe end-cap 32, in drift tube
Three permanent magnetism quadrupole magnetic arranged in the form of focusing-diverging-focusing (FDF) are axially arranged with along the drift tube main body inside main body 31
Iron 5, and the magnetic center of permanent magnetism quadrupole electromagnet 5 is overlapped with the machine center of drift tube；In drift tube main body 31 and permanent magnetism quadrupole magnetic
It is equipped with cyclic water jacket 7 between iron 5, circumferentially uniformly distributed circulating water chennel is opened up on the lateral wall of the cyclic water jacket.Second support bar 6
For hollow structure, second support bar 6 passes sequentially through electron beam welding structure by stainless steel 61, the first bronze medal bar 62 and the second bronze medal bar 63
At one end of stainless steel 61 is connect with 2 screw of ridge structure, and 63 other end of the second bronze medal bar is embedded in 31 top of drift tube main body or bottom
Portion's (the present embodiment is bottom), and the end is equipped with the through-hole being connected to circulating water chennel in cyclic water jacket 7, the second bronze medal bar 63 and drift
Pipe main body 31 and 7 joint of cyclic water jacket are welded and fixed；Second bronze medal bar 63, will support by the second bronze medal bar 63 as water column is divided
Inside and outside two layers of water route of bar is oriented to, and flows it in the circulating water chennel of cyclic water jacket 7, forms circulation, to drop for drift tube 3
Temperature.In drift tube main body 31 and the welding process of support rod 6, a technique head 35 is clamped by fixture to fix drift tube master
Body, the technique head are the column structures by mill out when roughing to drift tube main body, and are arranged opposite with support rod 6
Drift tube outer body wall on, drift tube main body 31 and support rod 6 welding after the completion of milling remove the technique head.Drift pipe end-cap 32
It is fixed with drift tube main body 31 in the following manner: first carries out electron beam welding in the stitching portion of the end cap and drift tube main body 31
It connects to form the first weld seam, then carries out electronics again at each beam spot beam radius distance of first weld seam or so deviateing
Beam welding, and drift about pipe end-cap 32 in the welding process, weld interval is carried out to guarantee that drift tube body temperature is no more than three times
The invalid temperature of permanent magnetism quadrupole electromagnet 5.
The specific implementation of each building block and function declaration are as follows in the embodiment of the present invention:
The drift tube accelerator of the present embodiment is used for KONUS draft tube linac, main body, that is, vacuum radio frequency resonance
Chamber 1 is a tapered cylinder vacuum cavity, wherein feed-in radio frequency, forms the electromagnetic field of approximation TE110 mode.With particle energy
Increase, individual unit (length of 1/2 β λ be a unit, wherein β be charged particle speed and vacuum light speed ratio, λ
For the free wavelength of the corresponding vacuum of resonance frequency) shunting impedance can decline, the accelerating field on bunch can be dropped in high-energy tail
It is low, using the available field distribution more evenly of the cylinder vacuum chamber of taper.Since the electromagnetic field of TE mode produces in the vacuum chamber
Life is along the magnetic field in bunch direction, and perpendicular to bunch, the changes of magnetic field along bunch direction can generate electric field between two ridge structures 2
Voltage, adjacent drift tube is connected from different ridge structures respectively by support rod, thus the gap between two drift tubes
Voltage is formed, charged ion and proton are accelerated.The specific implementation of the present embodiment longitudinal direction bunching section A and 0 ° of accelerating sections B and existing
There is KONUS draft tube linac identical, details are not described herein again.
The present embodiment improvements over the prior art are embodied in transverse focusing section C, and single permanent magnetism quadrupole electromagnet 5 is in drift tube
Arrangement mode referring to Fig. 6, by the different magnetic patch 51 of muti-piece pole orientation, (the present embodiment uses each permanent magnetism quadrupole electromagnet respectively
16 pieces of magnetic patch, but not limited to this) and the composition of cutting ferrule 52, the assembling to magnetic patch 51 is realized by cutting ferrule 52, by outside cutting ferrule 52
Respectively arranged pin 53 and pin hole determine permanent magnetism quadrupole electromagnet 5 in drift tube master on 7 inner sidewall of side wall and cyclic water jacket
Setting angle in body 31.
The magnetic field gradient of permanent magnetism quadrupole electromagnet is calculated according to following formula in the present embodiment:
Wherein BrIt is the surface mximum residual magnetism of permanent magnetism quadrupole electromagnet, M is the number of magnetic patch in permanent magnetism quadrupole electromagnet, r1For forever
The internal diameter of magnetic quadrupole electromagnet, r2For the outer diameter of permanent magnetism quadrupole electromagnet.Electric quadrupole magnetic in existing KONUS draft tube linac
The parameter of iron is internal diameter r120mm, outer diameter r2160mm, 50~80mm of length, magnetic field gradient F are less than 110T/m.As standard
Words, in the case where not changing the internal diameter and length of magnet, reach identical magnetic field gradient requirement, the outer diameter of permanent magnetism quadrupole electromagnet
r2Only 48mm, so that the drift pipe size of the transverse focusing section of KONUS draft tube linac greatly reduces, such as
Shown in the region C of Fig. 3.The drift pipe size of transverse focusing section becomes smaller, then the coupled problem of cavity is addressed, to avoid cutting
Fall coupling (in Fig. 2 C region shown in) of a part of ridge structure for cavity, so that the processing is simple for the ridge structure of cavity.
The process of drift tube is specific as follows in the present embodiment transverse focusing section C:
1) individually cross machine focuses each component in section C, including drift tube main body 31 and drift pipe end-cap 32, permanent magnetism quadrupole
Magnet 5, stainless steel 61, the first bronze medal bar 62 and the second bronze medal bar 63, cyclic water jacket 7；Stainless steel 61 and the first bronze medal bar 62 are led to
Electron beam welding is crossed to weld together；By drift tube main body 31, the second bronze medal bar 63 together with the Welding of cyclic water jacket 7；It is right
Drift tube main body 31 carries out roughing, and a technique head (the present embodiment is milled out on the drift tube body 31 opposite with support rod 6
Using cylinder, the size and holding clamp of the technique head match), so as to form first structure.Wherein, 61 He of stainless steel
There are 1mm surpluses for the shape of first bronze medal bar 62, and interior shape is in place；The shape of second bronze medal bar 63 stays 2mm surplus, and inside dimension is in place；It follows
In place, inside dimension stays 3mm surplus to the outside dimension of ring water jacket 7；The outside dimension of drift tube main body 31 stays 2mm surplus, and inside dimension is in place；
Drift about pipe end-cap inside and outside size in place.
2) permanent magnetism quadrupole electromagnet 5 is installed on inside the drift tube main body 31 of above-mentioned first structure by pin 53, is used
To drift about pipe end-cap 32 and drift tube main body 31 of electron beam welding welds together.It is to avoid electron beam by permanent magnetism four when welding
The magnetic field of pole magnet influences and reduces welding quality, using following welding procedure:
Electron beam first 2-1) is aligned drift pipe end-cap 32 and 31 joint of drift tube main body carries out welding and forms the first weldering
Seam, then (distance is determined that the distance of deviation is by the beam spot size of electron beam to the first weld seam of left and right deviation slight distance respectively
The radius of beam spot is welded for 0.1mm) again in the present embodiment, and weld interval certain time is (when the interval three times
Between determined by the power of electron beam and the heat dispersal situations of drift tube main body, in the present embodiment be 10min), and use thermometric test paper
Complete monitoring drift tube temperature, no more than the invalid temperature (failure of the present embodiment permanent magnetism quadrupole electromagnet of permanent magnetism quadrupole electromagnet 5
Temperature is 100 degrees Celsius), so as to form the second structure.
After the completion of 2-2) welding, light-exposed processing is carried out (really convenient for outer circle center to the outer circle of the second obtained structure
It is fixed), the Distribution of Magnetic Field of second structure, calculating magnetic field integral are measured, and integrate and carry out with the initial magnetic field of permanent magnetism quadrupole electromagnet 5
Compare, meanwhile, according to the Distribution of Magnetic Field of the permanent magnetism quadrupole electromagnet 5 of measurement, circle center outside calculating magnetic field center and the second structure
Deviation；If the difference of magnetic field integral carries out step 3) within the scope of measurement error；Otherwise return step 1), electricity is ensured with this
Beamlet welding process does not damage 5 iron of permanent magnetism quadrupole electromagnet.
3) according to the outer circle centre deviation of the magnetic field center of calculating and the second structure, with outside the second structure of lathe process
Circle guarantees machine center (i.e. outer circle axis) concentricity < 0.02mm of magnetic field center axis and drift tube, then with the second structure
Shape on the basis of, with the mating surface of the upper second bronze medal bar 63 and the first bronze medal bar 62 of the second structure of lathe process.
4) technique head 35 milled out is clamped by conventional clamp, to the second bronze medal bar 63 in the first bronze medal bar 62 and the second structure
Mating surface carries out electron beam welding, obtains third structure.By mill out technique head avoid directly clamping the second structure cause to float
Move the deformation of 31 periphery of pipe main body.
5) shape slightly repaired with lathe on drift tube (keeps the position dimension of the mounting surface and drift tube hub on support rod full
The error requirements of sufficient technological design), and magnetic-field measurement is carried out to permanent magnetism quadrupole electromagnet 5, the magnetic field center axis obtained according to measurement
Line and drift tube hub deviation, again in lathe refine third structure drift tube main body 31 shape, use lathe process thereafter
The structures such as the conical surface of drift tube, measurement magnetic field ensures magnetic center and machine center processing in place again after the completion of refine, then with
On the basis of third structure in place with lathe finishing 61 mounting surface of stainless steel.
6) technique head 35 in milling machine mill off drift tube main body 31 is used, and processing 63 bottom of the second bronze medal bar and technique head remove
The surface smoothness of position is to 1.6 μm afterwards, so far, completes in transverse focusing section C drift tube together with the processing of support rod.
The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although with reference to the foregoing embodiments
Invention is explained in detail, those skilled in the art should understand that: it still can be to aforementioned each implementation
Technical solution documented by example is modified or equivalent replacement of some of the technical features；And these modification or
Replacement, the spirit and scope for technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution.
Claims (4)
1. a kind of interdigital using permanent magnetism quadrupole electromagnet indulges magnetic mode shift pipe linear accelerator, including along vacuum radio frequency resonance
Multiple drift tubes of chamber central axis installation, are symmetrically arranged with a pair of of ridge in the upper and lower or left and right sides of the vacuum radio frequency resonant cavity cavity
Structure；The linear accelerator is divided into longitudinal bunching section A, 0 ° of accelerating sections B, transverse focusing section C along incoming particle beam direction of advance,
Adjacent drift tube passes through first support bar and the different ridge structures respectively in the longitudinal direction bunching section A and 0 ° of accelerating sections B
It is affixed；It is characterized in that, the drift tube in the transverse focusing section C is affixed by second support bar and the ridge structure, and institute
It states and is axially arranged with three along the drift tube inside the drift tube of transverse focusing section C with focusing-diverging-focus version arrangement permanent magnetism
The magnetic center of quadrupole electromagnet, each permanent magnetism quadrupole electromagnet is overlapped with the machine center of drift tube.
2. interdigital as described in claim 1 indulges magnetic mode shift pipe linear accelerator, which is characterized in that transverse focusing section C
Interior, the drift tube includes drift tube main body and drift pipe end-cap, is arranged forever described in three with focusing-diverging-focus version
Magnetic quadrupole electromagnet is arranged in the drift tube body interior；Circulation is equipped between the drift tube main body and permanent magnetism quadrupole electromagnet
Water jacket opens up circumferentially uniformly distributed circulating water chennel on the lateral wall of the cyclic water jacket；The second support bar is hollow structure, by
Stainless steel, the first bronze medal bar and the second bronze medal bar pass sequentially through electron beam welding composition, one end of the stainless steel and the ridge
Structural screws connection, the second bronze medal bar other end are embedded in the drift tube body top or bottom, and the end be equipped with it is described
The through-hole that circulating water chennel is connected in cyclic water jacket, the second bronze medal bar and drift tube main body and cyclic water jacket joint are welded solid
It is fixed；In the drift tube main body and the welding process of support rod, one is clamped by fixture, drift tube main body slightly add
Working hour mills out technique head to fix the drift tube main body, and the drift tube opposite with the support rod is arranged in the technique head
On main body lateral wall, milling removes the technique head after the completion of the drift tube main body and support rod welding.
3. interdigital as claimed in claim 2 indulges magnetic mode shift pipe linear accelerator, which is characterized in that the drift pipe end
Lid is to fix in the following manner with drift tube main body: first carrying out electronics in the stitching portion of the drift pipe end-cap and drift tube main body
Beam welds to form the first weld seam, is then carried out again at each beam spot beam radius distance of first weld seam or so deviateing
Electron beam welding, and drift about pipe end-cap in the welding process, weld interval is carried out to guarantee that drift tube body temperature does not surpass three times
Cross the invalid temperature of the permanent magnetism quadrupole electromagnet.
4. interdigital as claimed in claim 2 indulges magnetic mode shift pipe linear accelerator, which is characterized in that the technique head is
Column structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811272717.6A CN109413832B (en) | 2018-10-30 | 2018-10-30 | Interdigital longitudinal magnetic mode drift tube linear accelerator adopting permanent magnet quadrupole magnets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811272717.6A CN109413832B (en) | 2018-10-30 | 2018-10-30 | Interdigital longitudinal magnetic mode drift tube linear accelerator adopting permanent magnet quadrupole magnets |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109413832A true CN109413832A (en) | 2019-03-01 |
| CN109413832B CN109413832B (en) | 2020-06-19 |
Family
ID=65469702
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811272717.6A Active CN109413832B (en) | 2018-10-30 | 2018-10-30 | Interdigital longitudinal magnetic mode drift tube linear accelerator adopting permanent magnet quadrupole magnets |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109413832B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110337173A (en) * | 2019-03-27 | 2019-10-15 | 华中科技大学 | Electron Beam Focusing device |
| CN110549064A (en) * | 2019-06-18 | 2019-12-10 | 上海克林技术开发有限公司 | Buncher tool |
| CN112770473A (en) * | 2020-12-30 | 2021-05-07 | 中国原子能科学研究院 | Radio frequency accelerator and coupling cavity device thereof |
| CN113747651A (en) * | 2021-09-06 | 2021-12-03 | 清华大学 | Interdigital drift tube linear accelerator and linear accelerator system |
| CN114867184A (en) * | 2022-06-15 | 2022-08-05 | 中国科学院近代物理研究所 | Compact multi-ion accelerator treatment device and application thereof |
| US11483919B2 (en) | 2019-03-27 | 2022-10-25 | Huazhong University Of Science And Technology | System of electron irradiation |
| CN115515292A (en) * | 2022-10-20 | 2022-12-23 | 中国科学院上海高等研究院 | Proton injector |
| CN115607858A (en) * | 2022-09-09 | 2023-01-17 | 中国科学院近代物理研究所 | Cross rod type radio frequency quadrupole accelerator device |
| CN117065231A (en) * | 2023-07-28 | 2023-11-17 | 华中科技大学 | Dose optimizing device for high-energy electron radiotherapy |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05129099A (en) * | 1991-01-31 | 1993-05-25 | Mitsubishi Heavy Ind Ltd | Drift tube containing permanent magnet |
| US20050029970A1 (en) * | 2003-07-22 | 2005-02-10 | Ulrich Ratzinger | Drift tube accelerator for the acceleration of ion packets |
| WO2007144058A1 (en) * | 2006-06-12 | 2007-12-21 | Johann Wolfgang Goethe-Universität Frankfurt am Main | Modular linear accelerator |
| RU2397626C1 (en) * | 2009-01-27 | 2010-08-20 | Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" | Resonance accelerator drift tube |
| JP4869374B2 (en) * | 2009-03-25 | 2012-02-08 | 三菱電機株式会社 | H-mode drift tube linear accelerator |
| CN103026802A (en) * | 2010-07-12 | 2013-04-03 | 三菱电机株式会社 | Drift tube linear accelerator |
| JP2014175279A (en) * | 2013-03-13 | 2014-09-22 | Mitsubishi Electric Corp | Drift tube linear accelerator and particle beam therapy system |
| CN204046914U (en) * | 2014-07-24 | 2014-12-24 | 中国原子能科学研究院 | A kind of drift tube with support bar |
| CN204316859U (en) * | 2014-12-13 | 2015-05-06 | 中国科学院近代物理研究所 | A kind of mixed type ion accelerator |
-
2018
- 2018-10-30 CN CN201811272717.6A patent/CN109413832B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05129099A (en) * | 1991-01-31 | 1993-05-25 | Mitsubishi Heavy Ind Ltd | Drift tube containing permanent magnet |
| US20050029970A1 (en) * | 2003-07-22 | 2005-02-10 | Ulrich Ratzinger | Drift tube accelerator for the acceleration of ion packets |
| WO2007144058A1 (en) * | 2006-06-12 | 2007-12-21 | Johann Wolfgang Goethe-Universität Frankfurt am Main | Modular linear accelerator |
| RU2397626C1 (en) * | 2009-01-27 | 2010-08-20 | Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" | Resonance accelerator drift tube |
| JP4869374B2 (en) * | 2009-03-25 | 2012-02-08 | 三菱電機株式会社 | H-mode drift tube linear accelerator |
| CN103026802A (en) * | 2010-07-12 | 2013-04-03 | 三菱电机株式会社 | Drift tube linear accelerator |
| JP2014175279A (en) * | 2013-03-13 | 2014-09-22 | Mitsubishi Electric Corp | Drift tube linear accelerator and particle beam therapy system |
| CN204046914U (en) * | 2014-07-24 | 2014-12-24 | 中国原子能科学研究院 | A kind of drift tube with support bar |
| CN204316859U (en) * | 2014-12-13 | 2015-05-06 | 中国科学院近代物理研究所 | A kind of mixed type ion accelerator |
Non-Patent Citations (2)
| Title |
|---|
| BAICHUAN WANG ET AL.: "Fiducialization of the small-aperture quadrupoles based", 《NUCLEAR INSTRUMENTS AND METHODS IN PHYSICS RESEARCH A》 * |
| R. TIEDE ET AL.: "KONUS BEAM DYNAMICS DESIGNS USING H-MODE CAVITIES", 《PROCEEDINGS OF HADRON BEAM 2008, NASHVILLE, TENNESSEE, USA》 * |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11483919B2 (en) | 2019-03-27 | 2022-10-25 | Huazhong University Of Science And Technology | System of electron irradiation |
| CN110337173B (en) * | 2019-03-27 | 2020-11-06 | 华中科技大学 | Electron beam focusing device |
| CN110337173A (en) * | 2019-03-27 | 2019-10-15 | 华中科技大学 | Electron Beam Focusing device |
| CN110549064A (en) * | 2019-06-18 | 2019-12-10 | 上海克林技术开发有限公司 | Buncher tool |
| CN110549064B (en) * | 2019-06-18 | 2021-08-20 | 上海克林技术开发有限公司 | Buncher tool |
| CN112770473A (en) * | 2020-12-30 | 2021-05-07 | 中国原子能科学研究院 | Radio frequency accelerator and coupling cavity device thereof |
| CN113747651A (en) * | 2021-09-06 | 2021-12-03 | 清华大学 | Interdigital drift tube linear accelerator and linear accelerator system |
| CN114867184A (en) * | 2022-06-15 | 2022-08-05 | 中国科学院近代物理研究所 | Compact multi-ion accelerator treatment device and application thereof |
| CN114867184B (en) * | 2022-06-15 | 2023-03-14 | 中国科学院近代物理研究所 | Compact multi-ion accelerator treatment device and application thereof |
| CN115607858A (en) * | 2022-09-09 | 2023-01-17 | 中国科学院近代物理研究所 | Cross rod type radio frequency quadrupole accelerator device |
| CN115607858B (en) * | 2022-09-09 | 2023-11-21 | 中国科学院近代物理研究所 | Cross rod type radio frequency quadrupole accelerator device |
| CN115515292A (en) * | 2022-10-20 | 2022-12-23 | 中国科学院上海高等研究院 | Proton injector |
| CN117065231A (en) * | 2023-07-28 | 2023-11-17 | 华中科技大学 | Dose optimizing device for high-energy electron radiotherapy |
| CN117065231B (en) * | 2023-07-28 | 2024-02-02 | 华中科技大学 | Dose optimizing device for high-energy electron radiotherapy |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109413832B (en) | 2020-06-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109413832A (en) | Magnetic mode shift pipe linear accelerator is indulged using the interdigital of permanent magnetism quadrupole electromagnet | |
| CN109640508A (en) | A kind of vertical magnetic mode shift pipe linear accelerator of the focusing interdigital of separation | |
| TWI474762B (en) | Drift tube linear accelerator | |
| CN107079577B (en) | The design of high frequency compact low energy linear accelerator | |
| CN208590144U (en) | Linear accelerator and synchrotron | |
| CN113747651B (en) | Interdigital drift tube linear accelerator and linear accelerator system | |
| CN108566721B (en) | Linear accelerator and synchrotron | |
| CN112098734A (en) | High-precision electromagnetic combination measuring method and negative hydrogen cyclotron based on same | |
| US8421379B2 (en) | H-mode drift tube linac, and method of adjusting electric field distribution in H-mode drift tube linac | |
| Lu et al. | High power test of an injector linac for heavy ion cancer therapy facilities | |
| Degiovanni et al. | TERA high gradient test program of RF cavities for medical linear accelerators | |
| CN103167718B (en) | Single-mandril spoke type superconduction accelerating cavity and manufacture method thereof | |
| Brodhage et al. | First coupled CH power cavity for the FAIR proton injector | |
| Gai | Advanced accelerating structures and their interaction with electron beams | |
| Ishibashi et al. | Two-beam interdigital-H-type radio frequency quadrupole linac with direct<? format?> plasma injection for high intensity heavy ion acceleration | |
| CN105722297B (en) | Mixing accelerates to focus on superconductor cavity | |
| Qin et al. | Progress of HEPS accelerator system design | |
| Alesini et al. | Design and RF test of damped C-band accelerating structures for the ELI-NP linac | |
| Peauger et al. | JACOW: SWELL and Other SRF Split Cavity Development | |
| CN117580239A (en) | Ultrahigh frequency linear accelerator for medical isotope production and parameter design method | |
| Wang et al. | Positron Injector Accelerator and RF System for the ILC | |
| Zhu et al. | Development of a high precision small aperture quadrupole magnet with copper plate coils | |
| CN107860303B (en) | A kind of Electron bunch length diagnostic method and device | |
| Haimson et al. | A field symmetrized dual feed 2 MeV RF gun for a 17 GHz electron linear accelerator | |
| Kelly et al. | Superconducting 72 MHz beta= 0.077 Quarter-Wave Cavity for ATLAS |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |