JP2602824B2 - Electromagnet of charged particle device - Google Patents
Electromagnet of charged particle deviceInfo
- Publication number
- JP2602824B2 JP2602824B2 JP62055301A JP5530187A JP2602824B2 JP 2602824 B2 JP2602824 B2 JP 2602824B2 JP 62055301 A JP62055301 A JP 62055301A JP 5530187 A JP5530187 A JP 5530187A JP 2602824 B2 JP2602824 B2 JP 2602824B2
- Authority
- JP
- Japan
- Prior art keywords
- electromagnet
- charged particle
- particle beam
- cross
- quadrupole
- 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.)
- Expired - Fee Related
Links
Landscapes
- Particle Accelerators (AREA)
- Electromagnets (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は荷電粒子ビームを加速し或いは蓄積し、荷
電粒子装置、特に荷電粒子ビームを集束又は発散させる
ための荷電粒子装置の電磁石に関するものである。Description: TECHNICAL FIELD The present invention relates to a charged particle device for accelerating or accumulating a charged particle beam, and more particularly to an electromagnet of a charged particle device for focusing or diverging a charged particle beam. is there.
［従来の技術］ 第６図は、例えばアイエスエスピーレポート（ISSP00
8Z−4798,Ser.3No21、1988 9月発行）に示された従来の
荷電粒子ビーム装置を示す平面図であり、図において
（１）は荷電粒子ビームを蓄積するための蓄積リング、
（２）は荷電粒子ビームを蓄積リングに導くための入射
部ビームライン、（３）は荷電粒子ビームを偏向して平
衡軌道（４）を形成するための偏向電磁石、（５）は荷
電粒子ビームを偏向する際に発生するシンクロトロン放
射光（SOR...synchrotron orbital radiationの略語）
を外部に取り出してリソグラフィなどに利用するための
放射光ビームライン、（６）は荷電粒子ビームを集束さ
せるための４極電磁石、（７）は荷電粒子ビームの通路
である真空ドーナッツ、（８）は放射光を放射すること
による荷電粒子ビームのエネルギー損失を補い所定のエ
ネルギーに加速するための高周波空洞、（９）は荷電粒
子ビームを入射部ビームライン（２）から真空ドーナツ
（７）内に入射させるために荷電粒子ビームをパルス的
に偏向させるセプタムマグネットである。このように構
成された荷電粒子装置は、概括的に次のように動作す
る。まず、入射部ビームライン（２）から入射された荷
電粒子ビームがセプタムマグネット（９）によってパル
ス的に偏向されて、真空ドーナッツ（７）に入射され
る。その後、荷電粒子ビームは過渡的な軌道（バンア軌
道という）を経たのち偏向電磁石（３）と４極電磁石
（６）との配置により定まった平衡軌道（４）に入り、
この軌道に沿って長時間回転され続ける。一般的には、
入射部ビームライン（２）と真空ドーナッツ（７）とは
同一平面内に配置される。例えば、入射部ビームライン
（２）内の荷電粒子ビームが水平方向に進行して入射さ
れる場合には、セプタムマグット（９）によって荷電粒
子ビームは水平方向の偏向を受け、最終的に水平な平衡
軌道（４）に沿って回転される。ここで、平衡軌道
（４）に沿って回転される荷電粒子ビームが偏向電磁石
（３）の磁界によって偏向を受ける際に、制動放射によ
り放射光と呼ばれる電磁波が軌道接線方向に水平に放射
される。この放射光は偏向電磁石（３）中の荷電粒子ビ
ームの軌道上の任意の位置から得ることができるので、
通常放射光ビームライン（５）は多数設けられ装置の利
用効率の向上に役立てられる。第７図は四極電磁石
（６）の平衡軌道（４）に垂直な方向における断面形状
を示す断面図であり、（10）鉄心、（11）はこの鉄心
（10）の磁極面、（12）はコイル、（13）はコイル（1
2）が励磁されて発生される磁場（Ｂ）を表わす磁力
線、（ｘ），（ｙ）は座標を示しておりそれぞれ横軸、
縦軸である。第８図は第７図の第１象限の拡大図であ
り、（r0）は真空ドーナツ（７）が挿入される部分であ
るクリアボア半径で、ある。ここで、第２象限から第４
象限の磁極面（11）は第１象限のものと同一であるので
省略されている。[Prior Art] FIG. 6 shows, for example, an ISSP report (ISSP00
8Z-4798, Ser. 3No21, issued in September 1988) is a plan view showing a conventional charged particle beam device, in which (1) is a storage ring for storing a charged particle beam,
(2) is an incident beam line for guiding the charged particle beam to the storage ring, (3) is a deflection electromagnet for deflecting the charged particle beam to form an equilibrium orbit (4), and (5) is a charged particle beam. Synchrotron orbital radiation (SOR ... synchrotron orbital radiation)
(6) is a quadrupole magnet for focusing the charged particle beam, (7) is a vacuum donut which is a passage of the charged particle beam, (8) Is a high-frequency cavity for compensating the energy loss of the charged particle beam due to emission of radiation and accelerating the charged particle beam to a predetermined energy, and (9) transferring the charged particle beam from the incident part beam line (2) into the vacuum donut (7). This is a septum magnet that deflects a charged particle beam in a pulsed manner to make it incident. The charged particle device configured as above generally operates as follows. First, the charged particle beam incident from the incident part beam line (2) is pulse-deflected by the septum magnet (9) and is incident on the vacuum donut (7). Thereafter, the charged particle beam passes through a transient orbit (referred to as a Vaner orbit), and then enters a balanced orbit (4) determined by the arrangement of the bending electromagnet (3) and the quadrupole electromagnet (6).
It keeps rotating along this orbit for a long time. In general,
The entrance beam line (2) and the vacuum donut (7) are arranged in the same plane. For example, when the charged particle beam in the incident part beam line (2) travels in the horizontal direction and enters, the charged particle beam is horizontally deflected by the septum mug (9) and finally becomes horizontal. Is rotated along the equilibrium orbit (4). Here, when the charged particle beam rotated along the equilibrium trajectory (4) is deflected by the magnetic field of the deflecting electromagnet (3), an electromagnetic wave called radiation is radiated horizontally in the tangential direction of the trajectory by bremsstrahlung. . Since this radiation can be obtained from any position on the trajectory of the charged particle beam in the bending electromagnet (3),
Usually, a large number of radiation light beam lines (5) are provided to help improve the utilization efficiency of the apparatus. FIG. 7 is a sectional view showing a sectional shape of the quadrupole electromagnet (6) in a direction perpendicular to the equilibrium orbit (4), (10) an iron core, (11) a pole face of the iron core (10), and (12). Is a coil, (13) is a coil (1
2) Magnetic field lines representing the magnetic field (B) generated by excitation, (x) and (y) indicate coordinates, each being represented by the horizontal axis,
The vertical axis. FIG. 8 is an enlarged view of the first quadrant of FIG. 7, where (r 0 ) is the clear bore radius where the vacuum donut (7) is inserted. Here, from the second quadrant to the fourth quadrant
The pole face (11) of the quadrant is omitted since it is identical to that of the first quadrant.
次に、四極電磁石（６）について詳細に説明する。xy
平面は平衡軌道（４）に垂直な面であり座標原点は平衡
軌道（４）と一致する。従ってｙ軸は平衡軌道（４）が
作る面に垂直である。第８図に示される磁極面（11）の
断面円弧部の形状は、断面曲線例えば双曲線を示してい
るので、次式のように表すことができる。Next, the quadrupole electromagnet (6) will be described in detail. xy
The plane is a plane perpendicular to the equilibrium orbit (4), and the coordinate origin coincides with the equilibrium orbit (4). The y-axis is therefore perpendicular to the plane created by the equilibrium trajectory (4). The shape of the cross-section arc portion of the magnetic pole surface (11) shown in FIG. 8 shows a cross-section curve, for example, a hyperbola, and can be expressed by the following equation.
2xy＝r0 2 ……（１） 又、座標原点付近のｙ方向の磁場（By）は次式で表す
ことができる。2xy = r 0 2 (1) The magnetic field (By) in the y direction near the coordinate origin can be expressed by the following equation.
By＝ax ……（２） （但し、ａは定数） 周知のように（２）式は四極磁界成分に他ならない。
この四極磁界成分は必要な空間内において通常次の式で
示される程度の直線性が必要であると言われている。By = ax (2) (where a is a constant) As is well known, equation (2) is nothing but a quadrupole magnetic field component.
It is said that this quadrupole magnetic field component needs to have a degree of linearity in a required space in general, as shown by the following equation.
（以後、左辺の絶対値内をLNYと表わす）。 (Hereinafter, the absolute value on the left side is represented as LNY).
［発明が解決しようとする問題点］ 上記のような従来の荷電粒子装置の電磁石では、磁極
面の断面円弧部が双曲線になるように加工されているの
で、曲面加工しなければならず加工精度を上げることが
困難であるという問題点、その部分の加工に長時間を要
するため装置が高価になるという問題点があった。[Problems to be Solved by the Invention] In the electromagnet of the conventional charged particle device as described above, since the cross section of the magnetic pole surface is machined so as to be hyperbolic, the machining must be performed with a curved surface. In addition, there is a problem that it is difficult to raise the size of the device, and a problem that it takes a long time to process the portion and the device becomes expensive.
この発明は上記のような問題点を解決するためになさ
れたものであり、磁極面の断面円弧部の加工が極めて容
易で、十分な加工精度の磁極成分を備えた荷電粒子装置
の電磁石を得ることを目的とする。The present invention has been made in order to solve the above-described problems, and it is extremely easy to process a circular arc section of a magnetic pole surface, and to obtain an electromagnet of a charged particle device having a magnetic pole component with sufficient processing accuracy. The purpose is to:
［問題点を解決するための手段］ この発明に係る荷電粒子装置の電磁石は、荷電粒子ビ
ームを集束又は発散するための電磁石を含む荷電粒子装
置の電磁石の磁極面における断面円弧部の形状が曲線に
近似切削加工される前記電磁石において、前記曲線が垂
直部と水平部との連続的な組み合わせのみにより階段状
に近似切削加工するものである。[Means for Solving the Problem] The electromagnet of the charged particle device according to the present invention has a curved arc-shaped cross section on the pole face of the electromagnet of the charged particle device including the electromagnet for focusing or diverging the charged particle beam. In the electromagnet which is approximately cut, the curve is approximately cut in a stepwise manner only by a continuous combination of a vertical portion and a horizontal portion.
［作用］ この発明においては、電磁石の磁極面の断面円弧部の
曲線形状を、垂直部と水平部との連続的な組み合わせの
みにより階段状に近似切削加工して仕上げる。[Operation] In the present invention, the curved shape of the cross-section circular arc portion of the pole face of the electromagnet is finished by stepwise approximate cutting using only a continuous combination of the vertical portion and the horizontal portion.
［実施例］ 第１図はこの発明の一実施例の四極電磁石を備えた荷
電粒子装置を示す平面図、第２図は第１図に示された四
極電磁石の断面円弧部の形状を示す双曲線を階段状に近
似して表した断面図である。Embodiment FIG. 1 is a plan view showing a charged particle device provided with a quadrupole electromagnet according to an embodiment of the present invention, and FIG. 2 is a hyperbola showing a shape of a cross-sectional arc portion of the quadrupole electromagnet shown in FIG. FIG. 3 is a cross-sectional view that approximates a step shape.
第２図、第４図及ぴ第５図に於て（１）〜（５），
（７）〜（10）及び（12）は従来例と同一であるので説
明を省略する。（6A）はこの発明の四極電磁石、（11
A）は鉄心（10）の磁極面である。In FIGS. 2, 4 and 5, (1) to (5),
(7) to (10) and (12) are the same as in the conventional example, and the description thereof is omitted. (6A) is the quadrupole electromagnet of the present invention, (11)
A) is the pole face of the iron core (10).
上記のように構成されたこの発明の荷電粒子装置の電
磁石おいては、第２図に示されるように断面円弧部の形
状を示す双曲線を階段状を、垂直部と水平部との連続的
な組み合わせのみにより階段状に近似切削加工して仕上
げる。この場合、磁極面（11A）がｘ軸又はｙ軸に平行
な面（垂直面または水平面）のみで構成されているの
で、通常、工作機械や検査装置は、垂直・水平の直交座
標により位置決めや位置測定が厳密に行われるため、磁
極面（11A）の加工が極めて高精度に行なえると共に加
工径の寸法検査が極めて正確に実施できる。In the electromagnet of the charged particle device of the present invention configured as described above, as shown in FIG. 2, the hyperbolic shape indicating the shape of the circular arc section is stepwise, and the continuous portion between the vertical portion and the horizontal portion is formed. Approximate cutting in a step-like shape is completed only by the combination. In this case, since the magnetic pole surface (11A) is constituted only by a plane (vertical plane or horizontal plane) parallel to the x-axis or y-axis, the machine tool or the inspection device usually performs positioning and positioning by vertical / horizontal rectangular coordinates. Since the position measurement is strictly performed, the processing of the magnetic pole surface (11A) can be performed with extremely high precision, and the dimensional inspection of the processing diameter can be performed very accurately.
なお、上記実施例では、磁極面（11A）の断面円弧部
の形状を表わす双曲線を階段状に近似したが、磁極面
（11A）の断面円弧部の形状を表わす双曲線を、これに
極めて近い複数の直線による折れ線によって近似しても
よい。In the above embodiment, the hyperbola representing the shape of the cross section of the magnetic pole surface (11A) is approximated in a stepwise manner. May be approximated by a polygonal line formed by the straight line.
第３図は折れ線によって近似した場合の磁極面の断面
図であり、この断面図は四極電磁石の断面円弧部の形状
を座標を用いて表わした断面図、第４図は第３図の各座
標点を表にした座標管理図、第５図は第３図のから得ら
れる四極磁界成分の計算結果を描いたグラフ図である。FIG. 3 is a cross-sectional view of the magnetic pole surface when approximated by a polygonal line. This cross-sectional view shows the shape of the cross-sectional arc portion of the quadrupole electromagnet using coordinates, and FIG. 4 shows each coordinate in FIG. FIG. 5 is a graph showing the calculation results of quadrupole magnetic field components obtained from FIG. 3.
磁極面（11A）の加工は、第３図に示された点（ａ）
〜点（ｕ）のうち隣合う２点、例えば点（ａ）と点
（ｂ）、草（ｂ）と点（ｃ）、、、、を結んでできる直
線に従って行われる。隣合う各点は、全て直線で結ばれ
る。つまり、この実施例においては磁極面（11A）の断
面円弧部の形状を示す双曲線が複数の直線で近似され、
言い換えると磁極面（11A）が複数の直線に対応する平
面に従って加工される。The machining of the pole face (11A) is performed at the point (a) shown in FIG.
To point (u), for example, a straight line connecting two adjacent points, for example, point (a) and point (b), grass (b) and point (c),. Neighboring points are all connected by a straight line. That is, in this embodiment, a hyperbola indicating the shape of the cross-sectional arc portion of the pole face (11A) is approximated by a plurality of straight lines,
In other words, the pole face (11A) is machined according to a plane corresponding to a plurality of straight lines.
第４図にこの各点（ａ）〜（ｕ）を決定する座標が示
めされている。この座標に従って、磁極面（11A）が平
面で構成されるようにする。隣合う座標点の間隔距は主
として５〜6mmである。FIG. 4 shows coordinates for determining these points (a) to (u). In accordance with the coordinates, the magnetic pole surface (11A) is constituted by a plane. The distance between adjacent coordinate points is mainly 5 to 6 mm.
第５図はこのように加工された磁極面（11A）を備え
る四極電磁石（6A）のコイル（12）に17000（AT）の電
流を流した場合の磁界分布の数値計算結果を図示したも
のである。同図から明らかなように極めて直線性の優れ
た磁界分布が得られる。例えば、|x|≦4.8cmに於ては、 |LNY|≦0.7×10-4 また、上記の実施例では四極電磁石（6A）の場合につ
いて述べたが六極電磁石や八極電磁石等の磁極面が曲面
に構成されている電磁石であれば良。FIG. 5 shows a numerical calculation result of a magnetic field distribution when a current of 17000 (AT) is applied to the coil (12) of the quadrupole electromagnet (6A) having the pole face (11A) thus processed. is there. As is clear from the figure, a magnetic field distribution with extremely excellent linearity is obtained. For example, when | x | ≦ 4.8 cm, | LNY | ≦ 0.7 × 10 −4 In the above embodiment, the case of a quadrupole electromagnet (6A) was described. Any electromagnet having a curved surface is good.
更に、磁場の強さが時間的に変化するマグネットの場
合には渦電流を減少させるために、電磁石の鉄心が表面
絶縁の薄板を重ねた積層構造となる。Further, in the case of a magnet in which the strength of a magnetic field changes with time, the core of the electromagnet has a laminated structure in which thin plates of surface insulation are stacked in order to reduce eddy current.
この例として、第２図に示すように階段状の磁極面
（11A）を薄板で製作する場合、薄板端面の位置をずら
せるだけで良く製作が極めて容易である。As an example, as shown in FIG. 2, when the step-shaped magnetic pole surface (11A) is made of a thin plate, it is only necessary to shift the position of the end face of the thin plate, and the manufacture is extremely easy.
［発明の効果］ この発明は以上説明したとおり、荷電粒子ビームを集
束又は発散するための電磁石を含む荷電粒子装置の電磁
石の磁極面における断面円弧部の形状が曲線に近似切削
加工される前記電磁石において、前記曲線を垂直部と水
平部との連続的な組み合わせのみにより階段状に近似切
削加工して形成したので、高精度の機械加工装置を用い
ずとも高精度の加工が行え、また、仕上がり寸法検査を
極めて容易に実施できるため製品価格に影響する製品の
検査・試験時間を短縮することができるという経済的な
効果がある。[Effects of the Invention] As described above, the present invention provides an electromagnet in which the shape of a circular arc section on a magnetic pole surface of an electromagnet of a charged particle device including an electromagnet for converging or diverging a charged particle beam is approximated to a curve. In the above, since the curve was formed by stepwise approximate cutting only by a continuous combination of a vertical portion and a horizontal portion, high-precision machining can be performed without using a high-precision machining device, and Since the dimensional inspection can be performed very easily, there is an economic effect that the inspection and testing time of the product which affects the product price can be reduced.
第１図はこの発明の一実施例の四極電磁石を備えた荷電
粒子装置を示す平面図、第２図は１図に示された四極電
磁石の断面円弧部の形状を示す双曲線を階段状に近似し
て表した断面図、第３図は第１図に示された四極電磁石
の断面円弧部分を座標を用いて表した断面図、第４図は
第３図に示された各点を表にした座標管理図、第５図は
第３図の実施例により得られる四極磁界成分を表にした
グラフ図、第６図は従来の四極電磁石を備えた荷電粒子
装置の平面図、第７図は従来の四極電磁石の平衡軌道に
垂直な断面を示す断面図、第８図は従来の四極電磁石を
部分的に拡大して示した拡大断面図である。 図において、（１）は蓄積リング、（２）は入射部ビー
ムライン、（３）は偏向電磁石、（４）は平衡軌道、
（５）は放射光ビームライン、（6A）はこの発明の四極
電磁石、（７）は真空ドーナッツ、（８）は高周波空
洞、（９）はセプタムマグネット、（10）は鉄心、（11
A）は鉄心（10）の磁極面、（12）はコイルである。 なお、各図中、同一符号は同一または相当部分を示す。FIG. 1 is a plan view showing a charged particle device provided with a quadrupole electromagnet according to one embodiment of the present invention, and FIG. 2 is a stepwise approximation of a hyperbola showing the shape of a circular cross section of the quadrupole electromagnet shown in FIG. FIG. 3 is a cross-sectional view of the quadrupole electromagnet shown in FIG. 1 using coordinates, and FIG. 4 is a table showing each point shown in FIG. FIG. 5 is a graph showing a quadrupole magnetic field component obtained by the embodiment of FIG. 3, FIG. 6 is a plan view of a conventional charged particle device having a quadrupole electromagnet, and FIG. FIG. 8 is a cross-sectional view showing a cross section perpendicular to the equilibrium orbit of the conventional quadrupole electromagnet, and FIG. 8 is an enlarged cross-sectional view showing the conventional quadrupole electromagnet partially enlarged. In the figure, (1) is a storage ring, (2) is an incident part beam line, (3) is a bending electromagnet, (4) is a balanced orbit,
(5) is a synchrotron beam line, (6A) is a quadrupole electromagnet of the present invention, (7) is a vacuum donut, (8) is a high-frequency cavity, (9) is a septum magnet, (10) is an iron core, (11)
A) is the pole face of the iron core (10), and (12) is the coil. In the drawings, the same reference numerals indicate the same or corresponding parts.
Claims (1)
電磁石を含む荷電粒子装置の電磁石の電磁面における断
面円弧部の形状が曲線に近似切削加工される前記電磁石
において、前記曲線が垂直部と水平部との連続的な組み
合わせのみにより階段状に近似切削加工されることを特
徴とする荷電粒子装置の電磁石。1. An electromagnet in which the shape of a circular arc section on an electromagnetic surface of an electromagnet of a charged particle device including an electromagnet for converging or diverging a charged particle beam is approximated by a curve, wherein the curve is a vertical portion. An electromagnet for a charged particle device characterized in that it is approximately cut in a step-like manner only by a continuous combination with a horizontal portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62055301A JP2602824B2 (en) | 1987-03-12 | 1987-03-12 | Electromagnet of charged particle device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62055301A JP2602824B2 (en) | 1987-03-12 | 1987-03-12 | Electromagnet of charged particle device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63224200A JPS63224200A (en) | 1988-09-19 |
| JP2602824B2 true JP2602824B2 (en) | 1997-04-23 |
Family
ID=12994745
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62055301A Expired - Fee Related JP2602824B2 (en) | 1987-03-12 | 1987-03-12 | Electromagnet of charged particle device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2602824B2 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5152890A (en) * | 1974-09-26 | 1976-05-10 | Shigekazu Ikegami | TAKYOKUJIBASOCHI |
| DE3321117A1 (en) * | 1983-06-10 | 1984-12-13 | Siemens AG, 1000 Berlin und 8000 München | MAGNETIC MULTIPOLE N-TERM ORDER |
-
1987
- 1987-03-12 JP JP62055301A patent/JP2602824B2/en not_active Expired - Fee Related
Non-Patent Citations (1)
| Title |
|---|
| 理化学研究所報告４０［１］（１９６４）第１〜１０頁 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63224200A (en) | 1988-09-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3984687A (en) | Shielded magnetic lens and deflection yoke structure for electron beam column | |
| US3541328A (en) | Magnetic spectrograph having means for correcting for aberrations in two mutually perpendicular directions | |
| US3911321A (en) | Error compensating deflection coils in a conducting magnetic tube | |
| US10332718B1 (en) | Compact deflecting magnet | |
| JP2602824B2 (en) | Electromagnet of charged particle device | |
| US3787790A (en) | Magnetic mass spectrometer with shaped, uniformly saturating magnetic poles | |
| Kerst et al. | An 80‐Mev Model of a 300‐Mev Betatron | |
| Herminghaus et al. | Beam optics and magnet technology of the microtron in Mainz | |
| Dworski et al. | Low aberration permanent hexapole magnet for atom and molecular beam research | |
| JP2565889B2 (en) | Electromagnet for charged particle device | |
| US2824987A (en) | Electron optical elements and systems equivalent to light optical prisms for charge carriers in discharge vessels | |
| CN110455249B (en) | Multipole magnet collimation method based on three-coordinate measuring machine | |
| JP3397347B2 (en) | Omega filter | |
| EP0368489A1 (en) | A core for a magnetic multipole lens | |
| JP4066351B2 (en) | Electromagnet for fixed magnetic field alternating gradient accelerator | |
| JPH0672959B2 (en) | Charged particle device magnet | |
| JPH0340360B2 (en) | ||
| US3393385A (en) | Quadrupole magnet with reduced field distortion | |
| JPH08111311A (en) | Highly accurate core for electromagnet | |
| Wang | Computer calculation of deflection aberrations in electron beams | |
| JPH03141615A (en) | Solid mass iron core electromagnet | |
| JPH02244547A (en) | High precision quadruple pole magnetic lens of assemble type | |
| Langenbeck et al. | Shaping of pole ends to minimize field errors in quadrupole magnets | |
| JP2825900B2 (en) | High precision quadrupole magnetic lens and manufacturing method thereof | |
| Clark et al. | Operation of the LBL ECR source injection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |