JPWO2012117563A1 - Electromagnetic power supply control system and control method for synchrotron and synchrotron - Google Patents

Abstract

In a synchrotron in which a deflection electromagnet performs both beam deflection and trajectory correction, excitation adjustment of the deflection electromagnet can be easily performed. The computer 401 separately creates and manages the main pattern for beam acceleration / deceleration common to the deflection electromagnet and the pattern for beam trajectory correction for each deflection electromagnet. The control device 402 outputs the result of adding the main pattern and the correction pattern to the electromagnet power sources 403a to 403d, and the electromagnet power sources 403a to 403d excite the deflection electromagnets 102a to 102d according to the sum result.

Description

  The present invention relates to a synchrotron electromagnet power supply control system and control method for accelerating a charged particle beam, and a synchrotron.

  The synchrotron accelerates an incident charged particle beam (hereinafter referred to as a beam) after being accelerated to some extent by a linear accelerator to a desired energy and emits the beam to a beam utilization facility such as a particle beam cancer treatment apparatus.

  In the synchrotron, the beam circulates in an annular vacuum duct and accelerates to a desired energy by repeatedly passing through a high-frequency acceleration cavity. The synchrotron has a deflecting electromagnet for deflecting the beam, a monitor for measuring the position of the beam, and a correction electromagnet (steering electromagnet) for adjusting the beam trajectory based on the measurement result in order to make the beam circulate on the same orbit. Each synchrotron device is designed and installed so that the deflected beam circulates in the same orbit, but in reality, the axis of the beam slightly shifts due to the shape error and installation error of each device. The beam trajectory is corrected by the steering electromagnet.

  When there is a steering electromagnet, each deflecting electromagnet need only bend the beam at the same angle regardless of the deviation of the beam trajectory, and is excited with the same intensity by a common power source. On the other hand, since the steering electromagnet for correcting the beam trajectory needs to change the excitation intensity in accordance with the deviation of the beam trajectory, it is excited with different intensity by each individual power source.

  As described above, in the synchrotron, the deflection electromagnet excited by the common power source deflects the beam, and the steering electromagnet excited by the individual power source generally corrects the beam trajectory. An example of this type of synchrotron is disclosed in Patent Document 1.

  On the other hand, in a synchrotron in which the deflection electromagnet not only deflects the beam but also corrects the beam trajectory, the deflection electromagnet corrects the beam trajectory by changing the excitation intensity and finely adjusting the deflection angle of the beam. . Like the above-described general synchrotron steering electromagnets, each deflecting electromagnet needs to change the excitation intensity in accordance with the beam trajectory shift, and is therefore excited with different intensities by an individual power source instead of a common power source.

  As described above, an example of a synchrotron in which a deflection electromagnet is controlled by an individual power source and performs beam deflection and trajectory correction is disclosed in Non-Patent Document 1. In this paper, “The 12 main dipoles are excited in pairs by 6 Magnet Power Supplies (MPS). (Omitted) These errors can be corrected to around 1 mm with the 6 main dipole power supplies and the 6 vertical corrector magnets.” Have been described. In this example, twelve deflection electromagnets are excited as a set by individual power sources, and the beam trajectory error in the horizontal direction is corrected.

  The synchrotron repeats “incidence-acceleration-extraction-deceleration” of the beam at a predetermined cycle, and the deflecting electromagnet repeats the excitation intensity pattern at a predetermined cycle according to the change of the beam energy (acceleration). When the deflection electromagnet only deflects the beam and the steering electromagnet corrects the beam trajectory, excitation intensity pattern data is set for one common power source. On the other hand, when the deflecting electromagnet performs both beam deflection and trajectory correction, different pattern data is set for each deflecting electromagnet power source.

JP 2006-228579 A

S.P. Moller, "Status of the Particle Therapy Accelerator System Built by DANFYSIK A / S", EPAC08 (TUPP124), 2008 (Moller o is a diagonal slash to o)

  As described in Patent Document 1, the synchrotron in which the deflecting electromagnet only deflects the beam and the steering electromagnet corrects the trajectory of the beam requires a space for installing the steering electromagnet. There is a problem.

  In the synchrotron described in Non-Patent Document 1, since the deflecting electromagnet performs both beam deflection and trajectory correction, the steering electromagnet is unnecessary, and the synchrotron can be downsized.

  However, the synchrotron in which the deflection electromagnet performs both beam deflection and trajectory correction has two problems in electromagnet power control.

  First, there is a problem due to individualization of excitation intensity patterns. As described above, when the deflecting electromagnet does not perform beam trajectory correction, a pattern is set for one common power source. On the other hand, when the deflecting electromagnet performs beam trajectory correction, it is necessary to set different patterns for the respective power supplies. Therefore, the number of patterns increases, and it takes time to adjust the patterns. For example, assuming that the beam trajectory is shifted outward as a whole, the excitation intensity of all the deflection electromagnets is uniformly increased to increase the beam deflection angle, and the trajectory is moved inward. At that time, when each deflection electromagnet is excited by a common power source, one pattern to be set to the common power source may be adjusted. On the other hand, when the deflection electromagnets are excited by individual power sources, the patterns corresponding to the number of deflection electromagnet power sources must be adjusted.

  Secondly, there is a problem that, among the excitation intensity patterns, excitation adjustments for beam trajectory correction are difficult to distinguish on the graph. When the deflection electromagnet does not perform beam trajectory correction, an excitation intensity pattern corresponding to beam acceleration / deceleration is set in the deflection electromagnet power supply, and an excitation adjustment pattern for beam trajectory correction is set in the steering electromagnet power supply separately. On the other hand, when the deflecting electromagnet performs beam trajectory correction, the excitation intensity pattern set for each deflecting electromagnet power source has the excitation intensity slightly changed according to the amount of excitation greatly changed according to the beam acceleration / deceleration and the deviation of the beam trajectory. It also serves as an adjustment. The excitation adjustment amount for correcting the beam trajectory is very small with respect to the excitation intensity corresponding to the beam acceleration / deceleration. Therefore, when creating pattern data on a graph, it is difficult to determine the excitation adjustment for beam trajectory correction, and adjustment is difficult.

  An object of the present invention is to provide an electromagnet power supply control system and control method, and a synchrotron capable of easily adjusting excitation of the deflection electromagnet in a synchrotron in which the deflection electromagnet performs both beam deflection and trajectory correction. is there.

  In order to achieve the above object, in the present invention, the excitation intensity pattern of each deflection electromagnet is created and managed separately into a main pattern corresponding to beam acceleration / deceleration and a pattern for beam trajectory correction. The main pattern is common to the deflection electromagnets of all the deflection units, and the correction pattern is individual for the deflection electromagnets of each deflection unit. During operation, the result of adding the common main pattern and the individual correction patterns is set for each deflection electromagnet power source.

  According to the present invention, the following effects can be obtained.

  First, when uniformly changing the excitation amount of all deflection electromagnets, if one of the main patterns that require a large amount of beam bending is troublesome to adjust the excitation, it will be reflected in the change electromagnet of all deflection units. The excitation adjustment is easy.

  Second, in order to manage correction patterns with fine excitation changes separately from the main pattern with high excitation intensity, it is easy to distinguish excitation adjustments for beam trajectory correction when displaying pattern data in a graph. Adjustment is easy.

  As a result, in the synchrotron in which the deflecting electromagnet performs both beam deflection and trajectory correction, the excitation adjustment of the deflecting electromagnet can be performed easily and quickly, and the time for creating and adjusting the excitation intensity pattern can be shortened. .

It is a figure which shows the structure of the synchrotron provided with the deflection | deviation electromagnet which performs a beam trajectory correction based on the beam position monitor which is the application object of this invention, and its measurement result. It is a figure which shows the excitation intensity | strength pattern of the deflection electromagnet which changed the excitation intensity | strength according to beam acceleration / deceleration in order to always deflect | deviate a particle beam by the same angle. It is a figure which shows the control principle of this invention which manages separately the main pattern common to a deflection electromagnet, and an individual beam trajectory correction pattern, and makes the result of adding both patterns the pattern of each deflection electromagnet. It is a figure which shows the whole structure of the electromagnet power supply control system of a synchrotron. It is a figure which shows the detail of the function of the computer and control apparatus which comprise an electromagnet power supply control system. It is a flowchart which shows the creation process of the pattern data used by deflection electromagnet power supply control. It is a figure which shows the measurement result of each beam position monitor used when producing a deflection electromagnet pattern. The figure which shows an example of the graph display of the pattern for beam trajectory correction of the deflection electromagnet created by calculating | requiring the excitation adjustment amount for beam trajectory correction at the time of beam incidence and emission, and connecting the two points smoothly on the graph It is. It is explanatory drawing of the beam deflection radius of a deflection electromagnet. It is a figure which shows the excitation intensity | strength pattern of each deflection electromagnet when not implementing this invention. It is a figure which shows the detail of the function of the computer and control apparatus of the bending magnet power supply control system in the 2nd Embodiment of this invention. It is a figure which shows the detail of the function of the computer and control apparatus of the bending magnet power supply control system in the 3rd Embodiment of this invention. It is a figure which shows the correspondence of a deflection | deviation electromagnet and a power supply in case a synchrotron is provided with five or more deflection | deviation electromagnets.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
A first embodiment of the present invention will be described.
-Overall structure of synchrotron-
FIG. 1 is a block diagram of a synchrotron.

The synchrotron 100 includes a pre-accelerator 101, deflection electromagnets 102a, 102b, 102c, and 102d, a quadrupole electromagnet 103, a hexapole electromagnet 104, an electrostatic inflector 105, an electrostatic deflector 106, an outgoing septum electromagnet 107, an incident bump electromagnet 108, a beam. Position monitors 109a, 109b, 109c, 109d, a high-frequency acceleration cavity 110, and the like are provided. The deflection electromagnets 102a, 102b, 102c and 102d are arranged one by one in the four deflection units 102-1, 102-2, 102-3 and 102-4. The beam is preliminarily accelerated by the pre-stage accelerator 101, then enters the synchrotron 100 from the electrostatic inflector 105, is deflected by the deflecting electromagnets 102a, 102b, 102c, and 102d and circulates in the annular vacuum duct. Each time the beam passes through the high-frequency acceleration cavity 110, it is accelerated by applying a high-frequency voltage. When the beam reaches a desired energy, it is emitted from the exit septum electromagnet 107 to the beam utilization facility.
~ Excitation intensity pattern of deflection electromagnet ~
FIG. 2 is a diagram illustrating excitation intensity patterns of the deflection electromagnets 102a, 102b, 102c, and 102d.

The deflection electromagnets 102a, 102b, 102c, and 102d apply excitation strength as shown in FIG. 2 in accordance with the energy (acceleration) of the beam in order to deflect the beam. Since it is necessary to deflect the beam with a stronger force as the beam energy increases, the excitation intensity of the deflecting electromagnet is changed in accordance with the beam energy. Initially, the magnetic field is set low according to the low energy at the time of beam incidence (incident operation 201), and the magnetic field is strengthened every time the beam accelerates (acceleration operation 202), and the magnetic field is made constant according to the energy at the time of emission. After maintaining (extraction operation 203), the magnetic field is lowered for the next beam incidence (deceleration operation 204). Thus, the excitation intensity of the deflection electromagnet has a large mountain shape. Since the synchrotron 100 repeats “incidence-acceleration-extraction-deceleration” of the beam at a predetermined period, the change of the excitation intensity shown in FIG. The excitation intensity pattern is repeated in accordance with the period. This pattern needs to be changed according to the energy level at the time of emission, and a pattern corresponding to the desired type of emission energy is required.
~ Beam trajectory correction ~
The deflection electromagnets 102a, 102b, 102c, and 102d change the angle at which the beam is deflected by finely adjusting the excitation intensity so that the beam passes through the correct position at the positions of the beam position monitors 109a, 109b, 109c, and 109d. Correct the trajectory. For example, the deflection electromagnet 102a adjusts the beam deflection angle so that the beam trajectory coincides with a desired position at the point of the beam position monitor 109a. Since the deviation of the beam trajectory differs at each beam position monitor point, the correction angle of the beam trajectory is different for each electromagnet corresponding to each monitor, and the adjustment amount of the excitation intensity is also different. Therefore, conventionally, patterns corresponding to the number of deflecting electromagnets have been required. In other words, in order to emit a beam of 300 kinds of energy with the synchrotron 100 including four deflecting electromagnets, “a combination of four patterns × 300 patterns” is necessary.
-Control principle of the present invention-
FIG. 3 is a diagram showing the control principle of the present invention.

In the present invention, the pattern data of the deflecting electromagnet is the main pattern 301 common to the deflecting electromagnets 102a, 102b, 102c, 102d (deflecting units 102-1, 102-2, 102-3, 102-4) as shown in FIG. And deflection electromagnets 102a, 102b, 102c, 102d (deflecting units 102-1, 102-2, 102-3, 102-4) for correcting the beam trajectory to individual correction patterns 302a, 302b, 303c, 302d. Create and manage separately. The main pattern 301 is a pattern that matches the energy at the time of beam incidence and emission as shown in FIG. 2, that is, a pattern of excitation intensity that deflects the beam with stronger excitation as the beam energy is higher. The correction patterns 302a, 302b, 303c, and 302d are used to finely adjust the excitation intensity of the deflecting electromagnet to slightly change the beam deflection angle so that the beam trajectory matches the desired position at the position of the beam position monitor. This is an excitation adjustment pattern. “Main pattern 301 + correction patterns 302a, 302b, 303c, 302d = deflection electromagnet patterns 303a, 303b, 303c, 303d” (that is, the common main pattern 301 and the individual beam trajectory correction patterns 302a to 302d are added together and added together. The results are obtained as deflection electromagnet patterns 303a, 303b, 303c, and 303d), and the respective deflection electromagnets are excited according to the patterns 303a to 303d. In the present invention, the main pattern 301 may have 300 patterns corresponding to the number of energy.
-Overall configuration of electromagnet power control system-
FIG. 4 is a diagram showing an overall configuration of the electromagnet power supply control system of the synchrotron 100. As shown in FIG.

  The electromagnet power supply control system 410 includes a computer 401 (management device) having a plurality of terminals (display devices) 400a, 400b, and 400c, and a control device 402.

The operator creates the main pattern 301 and the correction patterns 302a to 302d by displaying the data of the main pattern 301 and the correction patterns 302a to 302d shown in FIG. 3 on the graph creation screen of the display unit of the terminals 400a, 400b, and 400c. And stored in the storage device of the computer 401. The computer 401 converts a plurality of stored pattern data into a form that can be used for power supply control such as a current / voltage pattern, and sets it in the memory of the control device 402. The control device 402 selects a pattern corresponding to the desired energy from a plurality of pattern data set in the memory in accordance with the timing of “incident-acceleration-exit-deceleration” of the beam, and generates an electromagnet power supply (Bending Magnet Power Supply). 403a, 403b, 403c, 403d. The electromagnet power supplies 403a, 403b, 403c, and 403d are individually provided in the deflection electromagnets 102a, 102b, 102c, and 102d (deflection units 102-1, 102-2, 102-3, and 102-4) and received from the control device 402. The deflection electromagnets 102a, 102b, 102c, and 102d are excited according to the values.
~ Details of functions of electromagnet power control system ~
FIG. 5 is a diagram showing details of functions of the computer 401 and the control device 402.

  As shown in FIG. 5, the computer 401 stores the main pattern 301 and the correction patterns 302a to 302d separately in the computer 401. The computer 401 adds both patterns and sets them in the control device 402 as follows. For example, the “incidence-acceleration-extraction-deceleration” period of the beam is 3 seconds (excluding the time when the emission is permitted to be variable), and the pattern data is composed of a total of 3000 points of excitation intensity data every 1 millisecond. In this case, the computer 401 adds the data at the same time of 3000 points of the main pattern and 3000 points of the correction pattern. The excitation intensity data is converted into a form that can be used for power supply control such as current / voltage data, and stored in the memory of the control device 402. The addition of the main pattern / correction pattern and the conversion from the excitation intensity data to the current / voltage data may be performed in the reverse order.

The output device 402a of the control device 402 selects a pattern that matches the desired output energy from a plurality of patterns stored in the memory, and sets the current / voltage data 3000 points to the deflection electromagnet power supplies 403a to 403d in accordance with the timing of each time point. Output. The control device 402 can also develop and output 3000 points of data to 30000 points. The electromagnet power supplies 403 a to 403 d excite the deflection electromagnets 102 a to 102 d in accordance with the current / voltage data received from the control device 402.
~ Excitation pattern data creation process ~
FIG. 6 is a flowchart showing a process for creating pattern data used in deflection electromagnet power control.

  The pattern data used in the deflection electromagnet power supply control is created as follows. First, the operator uses the terminal 400a of the computer 401 to create a main pattern 301 corresponding to desired output energy (step S501), sets only the main pattern 301 in the control device 402, and sets the synchrotron 100. drive. Then, the position of the beam at the time when the error is to be corrected (when the beam is incident, when the beam is emitted, etc.) is measured by the beam position monitors 109a, 109b, 109c, 109d, and the measurement result is displayed on the terminal 400a of the computer 401 (step 400a). S502).

  FIG. 7 is a diagram showing the measurement results of each beam position monitor. The measurement results of the first beam position monitors 109a, 109b, 109c, and 109d are, for example, a screen 601 in FIG. In the screen, 0 means that the beam trajectory is located at the center of the monitor, plus indicates that the trajectory is on the outside, and minus indicates that the trajectory is on the inside. As shown in the screen 601, when the desired beam trajectory position is 0 and the trajectory is entirely shifted outside the desired position, the beam deflection angle of all the deflection electromagnets 102a to 102d is increased to make the trajectory as a whole. Therefore, the excitation intensity of the main pattern common to the deflection electromagnets is increased (step S501). The operator adjusts the main pattern to bring the entire trajectory inward while looking at the screen 601 on the terminal 400a, for example, and the computer 401 increases the excitation intensity of the main pattern based on the operation result. The operation of step S501 for creating the main pattern, the operation of the synchrotron 100, and the operation of step S502 for measuring the beam trajectory are performed as shown in the screen 602 of FIG. Repeat until.

  In step S502 in which the synchrotron 100 is operated using the generated main pattern, the operator displays the generated main pattern on a graph, for example, on the terminal 400b of the computer 401 as appropriate, and the synchrotron according to the main pattern. Check if you are driving 100. The display of the main pattern at this time is, for example, as shown in FIG.

Next, different beam trajectory correction patterns 302a, 302b, 302c, and 302d are created for each deflection electromagnet (step S503). Here, the error amount (adjustment amount) of the beam trajectory at each of the beam position monitors 109a to 109d and the trajectory correction angle by the respective deflection electromagnets 102a to 102d are correlated, and the trajectory correction angle by each of the deflection electromagnets 102a to 102d. Is uniquely determined from the error amount (adjustment amount) of the beam trajectory at each of the beam position monitors 109a to 109d. As shown in the equation (1), the beam trajectory adjustment amounts ΔX1 to ΔXn at the positions of the beam position monitors 1 to n are the trajectory correction angles ΔX′1 to ΔX′n by the deflection electromagnets 1 to n and the square matrix A. Expressed as a product. Accordingly, the trajectory correction angles ΔX′1 to ΔX′n by the deflecting electromagnets are obtained by multiplying the beam trajectory adjustment amounts ΔX1 to ΔXn at the position of the beam position monitor by the inverse matrix of the square matrix A from the left. Since the synchrotron 100 of this embodiment includes four beam position monitors and four deflection magnets, A is a 4 × 4 square matrix. The square matrix A is obtained analytically from the equipment arrangement and operating conditions of the synchrotron 100, or obtained experimentally from the amount of change in orbital error when only one deflection electromagnet is changed.

ステップＳ５０３では、オペレータは、図７の画面６０２を見ながら各ビーム位置モニタ１０９ａ〜１０９ｄの地点におけるビーム軌道の誤差量（調整量）を設定する。計算機４０１は、上述の手法で各偏向電磁石１０２ａ〜１０２ｄによる軌道補正の角度を導き出し、その補正角度から励磁調整量を求める。また、計算機４０１は、主パターン３０１の複数の時点（ビーム入射時、出射時など）における励磁調整量を求め、例えば端末４００ｂのグラフ上でその点同士をなめらかに結ぶことで、各偏向電磁石のビーム軌道補正パターン３０２ａ〜３０２ｄを作成する。

In step S503, the operator sets an error amount (adjustment amount) of the beam trajectory at each of the beam position monitors 109a to 109d while viewing the screen 602 of FIG. The computer 401 derives the angle of trajectory correction by each of the deflecting electromagnets 102a to 102d by the above-described method, and obtains the excitation adjustment amount from the correction angle. Further, the calculator 401 obtains excitation adjustment amounts at a plurality of time points (at the time of beam incidence, at the time of emission, etc.) of the main pattern 301, and smoothly connects the points on the graph of the terminal 400b, for example, so that each deflection electromagnet Beam trajectory correction patterns 302a to 302d are created.

  In the present embodiment, an example in which the computer 401 obtains the excitation adjustment amount has been described. However, another external computer (not shown) connected to the computer 401 may obtain the excitation adjustment amount. In this case, the other computer outputs information on the obtained excitation adjustment amount to the computer 401. The computer 401 creates beam trajectory correction patterns 302a to 302d for each deflection electromagnet based on the excitation adjustment amount.

  FIG. 8 is a graph display of the beam trajectory correction pattern of the deflection electromagnet created by obtaining the excitation adjustment amount for beam trajectory correction at the time of beam entrance and exit and connecting the two points smoothly on the graph. It is a figure which shows an example. The operator performs fine adjustment of the correction pattern by manual operation while viewing the correction patterns 302a to 302d displayed on the terminal 400b of the computer 401 (that is, sets an error amount (adjustment amount) of the beam trajectory), The trajectory is adjusted to the desired position.

  Here, as shown in FIG. 8, the upper limit of excitation intensity (excitation intensity value on the vertical axis in FIG. 8) in the graph display of the excitation adjustment amount correction patterns 302a to 302d for beam trajectory correction is shown in FIG. A value smaller than the main pattern 301 shown is displayed (main pattern> correction pattern). Thereby, the excitation amounts of the correction patterns 302a to 302d are enlarged and displayed as compared with the main pattern 301, and the minute excitation adjustment amount becomes clear. For example, when the upper limit of the graph excitation intensity of the main pattern 301 is set to 3.00 Tm as shown in FIG. 2 and the upper and lower limits of the graph excitation intensity of the correction patterns 302a to 302d are set to ± 0.01 Tm as shown in FIG. The visibility (magnification rate) of the excitation intensity of the minute is 3000 times that of FIG. Therefore, it becomes easy for the operator to create and adjust the correction pattern.

  The synchrotron 100 is operated again using the excitation adjustment patterns of the respective bending electromagnets thus created, and the position of the beam trajectory is measured (step S504). The operation of step S503 for creating the correction patterns 302a to 302d, the operation of the synchrotron 100, and the operation of step S504 for measuring the beam trajectory are performed as shown in the screen 603 of FIG. Repeat until the position is reached.

Further, in step S504 in which the synchrotron 100 is operated using the generated correction pattern, the operator displays the generated beam trajectory correction patterns 302a to 302d in a graph on, for example, the terminal 400c of the computer 401, and synchronizes according to the correction pattern. Check if the TRON 100 is operating.
~effect~
As described above, in the present embodiment, the beam trajectory is first adjusted as a whole by the common main pattern 301, and then the points of the beam monitors 109a to 109d by the correction patterns 302a to 302d for the deflection electromagnets 102a to 102d. Adjust the beam trajectory at. In this process, the method of dividing each deflection electromagnet pattern into a main pattern and a correction pattern has the following advantages.

  First, if the common main pattern 301 is changed, it is reflected in the patterns of all the deflection electromagnets 109a to 109d. Therefore, if it is desired to uniformly change the strength of all the deflection electromagnets 109a to 109d, one common main pattern is changed. do it. When the beam trajectory is entirely shifted outward (screen 601), when the excitation intensity of the main pattern 301 is increased, the beam deflection angles of all the deflecting electromagnets 109a to 109d are increased, and the beam trajectory can be centered ( Screen 602).

  As described above, it is necessary to create pattern data for each emission energy. For example, when there are 300 types of desired emission energy, 300 sets of pattern data are required. If the same adjustment is performed on 300 sets of pattern data in the synchrotron 100 having four deflection electromagnets, the “300 × 4 = 1200” pattern for all the deflection electromagnets is changed. At this time, if there is a main pattern common to the deflecting electromagnets, 300 patterns corresponding to the number of energies may be changed.

  The creation of the main pattern 301 that greatly bends the beam for each desired output energy requires more time than the creation of the correction pattern for finely adjusting the beam trajectory. Accordingly, by making the main pattern 301 that greatly bends the beam a common pattern, it is possible to shorten the time for creating the entire pattern.

  Secondly, by dividing the main pattern having a high excitation intensity and the correction pattern having a fine excitation intensity, the excitation adjustment for beam trajectory correction becomes clear. For example, as shown in FIG. 9, in a synchrotron 100 having four deflection electromagnets with a deflection radius of 1.4 m, when deflecting a beam with energy of 250 MeV, the trajectory correction angle by each deflection electromagnet is 90 degrees, which is the original deflection angle. It remains at 0.2 to 0.3%. At this time, the excitation intensity patterns of the respective deflection electromagnets 102a to 102d in which the main pattern and the correction pattern are not separated are as shown in FIG. 10 (the solid line indicates the pattern including the beam trajectory correction, and the broken line indicates the beam trajectory correction). It is difficult to distinguish the excitation adjustment amount of each of the deflection electromagnets 102a to 102d.

  On the other hand, when the main pattern 310 and the correction patterns 302a to 302d are created separately and the beam trajectory correction patterns 302a to 302d of the deflecting electromagnets 102a to 102d are displayed in a graph, as shown in FIG. The visibility (magnification rate) of the excitation intensity corresponding to the trajectory correction can be enlarged and displayed 3000 times that of FIG. 2, and the operator can easily create and adjust the correction pattern.

Due to the above two advantages, it is possible to shorten the time for creating and adjusting the excitation intensity pattern.
<Second Embodiment>
FIG. 11 is a diagram showing details of the functions of the computer and the control device of the bending electromagnet power supply control system in the second embodiment of the present invention.

As shown in FIG. 11, the deflection electromagnet power control system 410A according to the second embodiment of the present invention is similar to the main pattern 301 common to the deflection electromagnet and the deflection, as in the first embodiment (FIG. 5). The beam trajectory correction patterns 302a to 302d for the individual electromagnets are created separately and stored in the computer 401A. The difference from the first embodiment is that the control device 402A does not add the common main pattern 301 and the individual correction patterns 302a to 302d but the computer 401A. That is, the computer 401A sets the main pattern 301 and the correction patterns 302a to 302d separately in the control device 402A, and the control device 402A adds up the main pattern 301 and the correction patterns 302a to 302d and stores them in the memory. When the control device 402A operates the synchrotron 100, the control device 402A selects the one corresponding to the desired output energy from the combined results 303a to 303d of the main pattern 301 and the correction patterns 302a to 302d, and outputs them to the respective deflection electromagnet power supplies 403a to 403d. To do.
<Third Embodiment>
FIG. 12 is a diagram showing details of the functions of the computer and the control device of the deflection electromagnet power supply control system in the third embodiment of the present invention.

As shown in FIG. 12, the deflection electromagnet control system 410B according to the third embodiment of the present invention is similar to the first embodiment (FIG. 5) and the second embodiment (FIG. 11) described above. The main pattern 301 common to the deflection electromagnets and the beam trajectory correction patterns 302a to 302d for the respective deflection electromagnets are created separately and stored in the computer 401B. The difference from the first and second embodiments is that the common main pattern 301 and the individual correction patterns 302a to 302d are not summed before the operation of the synchrotron 100, but the output device of the control device 402B during the operation. 402b is the point which outputs to electromagnet power supplies 403a-403d, adding in real time. That is, the control device 402B stores the main pattern 301 and the correction patterns 302a to 302d separately in a memory, and selects the main pattern 301 and the correction patterns 302a to 302d corresponding to the desired energy when operating the synchrotron 100. Both patterns are added together and output to the respective deflection electromagnet power supplies 403a to 403d.
<Others>
The present invention is not limited to the embodiment described above, and various modifications are possible. For example, the synchrotron 100 shown in FIG. 1 includes four deflection units on which deflection electromagnets are arranged, but may include five or more deflection units. Further, an electromagnet for correcting the trajectory in the vertical direction may be provided separately from the deflection electromagnet for correcting the beam trajectory in the horizontal direction (direction in which the beam is deflected). FIG. 13 shows such a modification. The left side of FIG. 13 shows the deflection unit of the above-described embodiment, and the deflection unit 102-2 is representatively shown among the four deflection units 102-1 to 102-4. The deflecting unit 102-2 includes one deflecting electromagnet 102b, and the deflecting electromagnet 102b and the electromagnet power supply 403b are connected by a power supply line 1001 at 1: 1. The right side of FIG. 13 shows a case where a plurality of deflection electromagnets are arranged in each deflection unit, as a representative of the deflection unit 102-2, as in the left side. The deflecting unit 102-2 includes two deflecting electromagnets 102b1 and 102b2, and the deflecting electromagnets 102b1 and 102b2 and the electromagnet power supply 403 are connected to each other via a power supply line 1002 at 2: 1. As described above, even when a plurality of deflecting electromagnets are arranged in each deflecting section, the same effect can be obtained by applying the present invention. The present invention can be applied to various forms of synchrotron electromagnet power supply control for correcting the beam trajectory by minutely changing the excitation amount of the deflection electromagnet.

DESCRIPTION OF SYMBOLS 100 Synchrotron 101 Front stage accelerator 102a, 102b, 102c, 102d Bending electromagnet 102b1.102b2 Bending electromagnet 102-1, 102-2, 102-3, 102-4 Deflection part 103 Quadrupole electromagnet 104 Hexapole electromagnet 105 Electrostatic inflector 106 Electrostatic deflector 107 Outgoing septum electromagnet 108 Incident bump electromagnet 109a, 109b, 109c, 109d Beam position monitor 110 High frequency acceleration cavity 201 Incident operation 202 Acceleration operation 203 Outgoing operation 204 Deceleration operation 301 Main patterns 302a, 302b, 302c common to the deflection electromagnets 302d Individual correction patterns 303a, 303b, 303c, and 303d for the deflection magnets Deflection electromagnet patterns (the sum of the main pattern and the correction pattern)
400a, 400b, 400c terminal (display device)
401 Computer (management device)
401A Computer (management device)
401B Computer (management device)
402 Control Device 402A Control Device 402B Control Device 402a Output Device (FIGS. 5 and 11)
402b Output device (FIG. 12)
403a, 403b, 403c, 403d Electromagnet power supply 410, 410A, 410B Electromagnet power supply control system 601, 602, 603 Measurement result display screen

[0004]
Thus, the amount of excitation greatly changes and the amount of fine adjustment of the excitation intensity according to the deviation of the beam trajectory can be used. The excitation adjustment amount for correcting the beam trajectory is very small with respect to the excitation intensity corresponding to the beam acceleration / deceleration. Therefore, when creating pattern data on a graph, it is difficult to determine the excitation adjustment for beam trajectory correction, and adjustment is difficult.
[0016]
An object of the present invention is to provide an electromagnet power supply control system and control method, and a synchrotron capable of easily adjusting excitation of the deflection electromagnet in a synchrotron in which the deflection electromagnet performs both beam deflection and trajectory correction. is there.
Means for Solving the Problems [0017]
In order to achieve the above object, in the present invention, the excitation intensity pattern of each deflection electromagnet is created and managed separately into a main pattern corresponding to beam acceleration / deceleration and a pattern for beam trajectory correction. The main pattern is common to the deflection electromagnets of all the deflection units, and the correction pattern is individual for the deflection electromagnets of each deflection unit. During operation, the result of adding the common main pattern and the individual correction patterns is set for each deflection electromagnet power source.
Effects of the Invention [0018]
According to the present invention, the following effects can be obtained.
[0019]
First, when changing the excitation amount of all deflection electromagnets uniformly, if one of the main patterns that require a large amount of beam bending is troublesome to adjust the excitation, it will be reflected in the deflection electromagnets of all deflection units. The excitation adjustment is easy.
[0020]
Second, in order to manage correction patterns with fine excitation changes separately from the main pattern with high excitation intensity, it is easy to distinguish excitation adjustments for beam trajectory correction when displaying pattern data in a graph. Adjustment is easy.
[0021]
As a result, in the synchrotron in which the deflecting electromagnet performs both beam deflection and trajectory correction, the excitation adjustment of the deflecting electromagnet can be performed easily and quickly, and the time for creating and adjusting the excitation intensity pattern can be shortened. .
Brief Description of Drawings

Claims (11)

A plurality of deflecting units (102-1 to 102-4) in which at least one deflecting electromagnet (102a to 102d) serving both as a charged particle beam deflection and a beam trajectory correction is disposed;
A plurality of electromagnet power supplies (403a to 403d) for individually exciting the deflection electromagnets arranged in the plurality of deflection units,
In the electromagnet power supply control system of the synchrotron (100) for accelerating the charged particle beam to a desired energy and emitting it to a beam utilization facility,
The excitation intensity patterns of the deflection electromagnets arranged in the plurality of deflection units are divided into a main pattern (301) common to the plurality of deflection units and individual beam trajectory correction patterns (302a to 302d) in the plurality of deflection units. A management device (401) created separately
At the time of acceleration / deceleration of the charged particle beam, the deflection electromagnets arranged in the plurality of deflection units are respectively excited according to a result of adding the common main pattern created by the management device and the individual beam trajectory correction patterns. A synchrotron electromagnet power control system, comprising: a control device (402) for controlling a plurality of electromagnet power supplies. In the synchrotron electromagnet power control system according to claim 1,
When the management device (401) creates the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d), the common main pattern data and the individual beam trajectory correction pattern data Display devices (400a to 400c),
The display device separately displays the common main pattern data and the individual beam trajectory correction pattern data in a graph, and expands the individual beam trajectory correction pattern data relative to the common main pattern data. An electromagnet power control system for synchrotrons, characterized by a graphical display. In the synchrotron electromagnet power control system according to claim 1,
The control device (402) adds the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) in advance, and stores only the resulting patterns (303a to 303d). A synchrotron electromagnet power control system. In the synchrotron electromagnet power control system according to claim 1,
The control device (402A) stores the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) separately, and further combines the patterns (303a to 302a). 303d), a synchrotron electromagnet power control system. In the synchrotron electromagnet power control system according to claim 1,
The control device stores the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) separately and separately adds the two patterns during acceleration / deceleration of the charged particle beam. An electromagnet power supply control system for a synchrotron, wherein the electromagnet power supplies (403a to 403d) are controlled.   A synchrotron comprising the electromagnet source control system (410; 410A; 410B) according to any one of claims 1-5. A plurality of deflecting units (102-1 to 102-4) in which at least one deflecting electromagnet (102a to 102d) serving both as a charged particle beam deflection and a beam trajectory correction is disposed;
A plurality of electromagnet power supplies (403a to 403d) for individually exciting the deflection electromagnets arranged in the plurality of deflection units,
In the electromagnet power control method of the synchrotron (100) for accelerating the charged particle beam to a desired energy and emitting it to a beam utilization facility,
The excitation intensity patterns of the deflection electromagnets arranged in the plurality of deflection units are divided into a main pattern (301) common to the plurality of deflection units and individual beam trajectory correction patterns (302a to 302d) in the plurality of deflection units. ) And create the first procedure separately,
At the time of acceleration / deceleration of the charged particle beam, the deflection electromagnets arranged in the plurality of deflection units are respectively excited according to a result of adding the common main pattern created in the first procedure and the individual beam trajectory correction patterns. And a second procedure of controlling the plurality of electromagnet power supplies. The synchrotron electromagnet power control method according to claim 7,
In the first procedure, when the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) are created, the common main pattern data and the individual beam trajectory correction pattern data are separately obtained. A method of controlling the electromagnet power supply of the synchrotron, wherein the individual beam trajectory correction pattern data is enlarged and displayed as a graph with respect to the common main pattern data. The synchrotron electromagnet power control method according to claim 7,
In the second procedure, the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) are added together in advance, and only the resulting patterns (303a to 303d) are stored. The synchrotron electromagnet power control method. The synchrotron electromagnet power control method according to claim 7,
In the second procedure, the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) are stored separately, and the resulting patterns (303a to 303d) are added together. A synchrotron electromagnet power control method characterized by storing. The synchrotron electromagnet power control method according to claim 7,
In the second procedure, the common main pattern (301) and the individual beam trajectory correction patterns (302a to 302d) are stored separately, and the two patterns are added together during acceleration / deceleration of the charged particle beam. While controlling the plurality of electromagnet power supplies (403a to 403d), a synchrotron electromagnet power control method.

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