# US 10,312,006 B2 · Undulator magnet, undulator, and radiation light generating device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,006 B2 - Document ID: US10312006B2 - Status: Granted - Kind: B2 - Application number: 16/117,586 - Filed: 2018-08-30 - Published: 2019-03-14 - Granted: 2019-06-04 - Earliest claimed: 2017-09-12 - Assignees: Inter-University Research Institute Corporation Hi - Applicants: Inter-University Research Institute Corporation High Energy Accelerator Research Organization - Inventors: Shigeru Yamamoto; Jun Taniguchi - Web page: https://patentgrep.com/patent/US10312006B2 ## CPC - H01F 7/0278: {for generating uniform fields, focusing, deflecting electrically charged particles (for magnetic separation by Lorentz force B03C1/023; specially adapted for NMR applications G01R33/383)} - H05H 7/04: Magnet systems {, e.g. undulators, wigglers (free-electron laser H01S3/0903)}; Energisation thereof - H05H 2007/041: {for beam bunching, e.g. undulators} - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H05H: PLASMA TECHNIQUE (apparatus or processes specially adapted for producing X-rays H05G2/00); PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS ## Abstract An undulator magnet having favorable transportation workability is provided. Specifically, an undulator permanent magnet used for an undulator is provided that generates radiation light by meandering electrons that travel in a first direction, wherein, in the undulator permanent magnet, one end surface in the first direction forms a first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, and when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3. ## Claims ### Claim 1 An undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in a first direction, wherein, in the undulator permanent magnet, one end surface in the first direction forms a first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, and when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3. ### Claim 2 (depends on 1) The undulator permanent magnet according to claim 1, wherein a magnitude of the second peak P2 is larger than a magnitude of the fourth peak P4. ### Claim 3 (depends on 1) The undulator permanent magnet according to claim 1, wherein a magnitude of the fifth peak P5 is larger than the magnitude of the third peak P3 and is smaller than the magnitude of the first peak P1. ### Claim 4 (depends on 1) The undulator permanent magnet according to claim 1, wherein the magnitude of the first peak P1 is larger than an average of magnitudes of the plurality of odd-numbered peaks from the side of the first connecting surface. ### Claim 5 (depends on 1) The undulator permanent magnet according to claim 1, wherein the magnitude of the third peak P3 is smaller than an average of magnitudes of the plurality of odd-numbered peaks from the side of the first connecting surface. ### Claim 6 (depends on 1) The undulator permanent magnet according to claim 1, wherein the magnitude of the first peak when viewed from the side of the other end surface in the first direction among the plurality of peaks is half of an average of magnitudes of the plurality of even-numbered peaks from the side of the first connecting surface. ### Claim 7 (depends on 1) The undulator permanent magnet according to claim 1, wherein widths of a plurality of magnetic poles formed on the magnetic pole surface are equal in the first direction from the first connecting surface to the other end surface in the first direction. ### Claim 8 (depends on 1) The undulator permanent magnet according to claim 1, wherein a convex connecting part that is convex in the second direction is provided on any one of one magnetic pole surface and the other magnetic pole surface in the second direction. ### Claim 9 (depends on 1) The undulator permanent magnet according to claim 1, wherein the first connecting surface has a convex connecting part that is convex in the first direction or a concave connecting part that is concave in the first direction. ### Claim 10 (depends on 1) The undulator permanent magnet according to claim 1, wherein a yoke is attached to a magnetic pole surface opposite to a magnetic pole surface that faces a path through which the electrons pass within the magnetic pole surface in the second direction. ### Claim 11 (depends on 1) The undulator permanent magnet according to claim 1, wherein the length of the yoke in the first direction is shorter than the length of the opposite magnetic pole surface in the first direction. ### Claim 12 (depends on 1) The undulator permanent magnet according to claim 1, wherein the length of the yoke in a third direction that is orthogonal to the first direction and the second direction is shorter than the length of the opposite magnetic pole surface in the third direction. ### Claim 13 (depends on 1) A pair of magnets formed by connecting the undulator permanent magnets according to claim 1 on the first connecting surfaces, wherein a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of one undulator permanent magnet of the pair of magnets and a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of the other undulator permanent magnet of the pair of magnets are opposite to each other. ### Claim 14 (depends on 1) The undulator permanent magnet according to claim 1, wherein the other end surface in the first direction is a second connecting surface connected to another undulator permanent magnet, wherein, when the plurality of peaks are represented as the first to n-th peaks Qn (n is an integer of 1 or more) in order from the side of the second connecting surface, a magnitude of the first peak Q1 is larger than a magnitude of the third peak Q3, and wherein a direction of a magnetic flux density of the first peak P1 and a direction of a magnetic flux density of the first peak Q1 are opposite to each other. ### Claim 15 (depends on 14) The undulator permanent magnet according to claim 14, wherein a magnitude of the second peak Q2 is larger than a magnitude of the fourth peak Q4. ### Claim 16 (depends on 14) The undulator permanent magnet according to claim 14, wherein a magnitude of the fifth peak Q5 is larger than the magnitude of the third peak Q3 and is smaller than the magnitude of the first peak Q1. ### Claim 17 (depends on 14) The undulator permanent magnet according to claim 14, wherein the magnitude of the first peak Q1 is larger than an average of magnitudes of the plurality of odd-numbered peaks from the side of the second connecting surface. ### Claim 18 (depends on 14) The undulator permanent magnet according to claim 14, wherein the magnitude of the third peak Q3 is smaller than an average of magnitudes of the plurality of odd-numbered peaks from the side of the second connecting surface. ### Claim 19 (depends on 14) The undulator permanent magnet according to claim 14, wherein one of the first connecting surface and the second connecting surface is one of a convex connecting part that is convex in the first direction and a concave connecting part that is concave in the first direction, and the other of the first connecting surface and the second connecting surface is the other of the convex connecting part and the concave connecting part. ### Claim 20 (depends on 14) The undulator permanent magnet according to claim 14, wherein widths of a plurality of magnetic poles formed on the magnetic pole surface are equal in the first direction from the first connecting surface to the second connecting surface. ### Claim 21 (depends on 14) The undulator permanent magnet according to claim 14, wherein, regarding the magnetic flux density distribution, an integral value of the magnetic flux density in the one magnetic pole is equal to an integral value of the magnetic flux density in the other magnetic pole. ### Claim 22 (depends on 1) An undulator that generates radiation light by meandering electrons, comprising: a vacuum chamber having a passage therein through which the electrons pass in a predetermined direction; and a pair of magnet arrays that are arranged to face each other with the passage therebetween in the vacuum chamber, wherein each of the pair of magnet arrays includes, on magnetic pole surfaces that face each other, magnetic poles that attract each other and are alternately arranged in the predetermined direction such that a magnetic flux density distribution having a plurality of peaks in the passage is generated, and a pair of magnets formed by connecting the undulator permanent magnets according to claim 1 on the first connecting surfaces, in an undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in a first direction, wherein, in the undulator permanent magnet, one end surface in the first direction forms a first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3, and wherein a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of one undulator permanent magnet of the pair of magnets and a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of the other undulator permanent magnet of the pair of magnets are opposite to each other. ### Claim 23 (depends on 15) An undulator that generates radiation light by meandering electrons, comprising: a vacuum chamber having a passage therein through which the electrons pass in a predetermined direction; and a pair of magnet arrays that are arranged to face each other with the passage therebetween in the vacuum chamber, wherein each of the pair of magnet arrays includes, on magnetic pole surfaces that face each other, magnetic poles that attract each other and are alternately arranged in the predetermined direction such that a magnetic flux density distribution having a plurality of peaks in the passage is generated, and a pair of magnets formed by connecting the undulator permanent magnets according to claim 15 on the first connecting surface and the second connecting surface. ### Claim 24 An undulator that generates radiation light by meandering electrons, comprising: a vacuum chamber having a passage therein through which the electrons pass in a predetermined direction; and a pair of magnet arrays that are arranged to face each other with the passage therebetween in the vacuum chamber, wherein each of the pair of magnet arrays includes, on magnetic pole surfaces that face each other, magnetic poles that attract each other and are alternately arranged in the predetermined direction such that a magnetic flux density distribution having a plurality of peaks in the passage is generated, and a pair of magnets formed by connecting a first connecting surface of an undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in a first direction in which one end surface in the first direction forms the first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, and when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3, and the first connecting surface has a convex connecting part that is convex in the first direction, and a first connecting surface or a second connecting surface of the undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in the first direction in which one end surface in the first direction forms the first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, and when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3, the other end surface in the first direction is the second connecting surface connected to another undulator permanent magnet, when the plurality of peaks are represented as the first to n-th peaks Qn (n is an integer of 1 or more) in order from the side of the second connecting surface, a magnitude of the first peak Q1 is larger than a magnitude of the third peak Q3, a direction of a magnetic flux density of the first peak P1 and a direction of a magnetic flux density of the first peak Q1 are opposite to each other, and one of the first connecting surface and the second connecting surface is a concave connecting part that is concave in the first direction, wherein a direction of a magnetic flux density of a first peak when viewed from the side of a connecting surface of the pair of magnets of a magnetic flux density distribution in the first direction of one undulator permanent magnet of the pair of magnets and a direction of a magnetic flux density of a first peak when viewed from the side of the connecting surface of a magnetic flux density distribution in the first direction of the other undulator permanent magnet of the pair of magnets are opposite to each other. ### Claim 25 An undulator that generates radiation light by meandering electrons, comprising: a vacuum chamber having a passage therein through which the electrons pass in a predetermined direction; and a pair of magnet arrays that are arranged to face each other with the passage therebetween in the vacuum chamber, wherein each of the pair of magnet arrays includes, on magnetic pole surfaces that face each other, magnetic poles that attract each other and are alternately arranged in the predetermined direction such that a magnetic flux density distribution having a plurality of peaks in the passage is generated, and a pair of magnets formed by connecting a first connecting surface of an undulator permanent magnet including a concave connecting part of the undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in the first direction in which one end surface in the first direction forms the first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3, and the first connecting surface has the concave connecting part that is concave in the first direction, and a first connecting surface or a second connecting surface of the undulator permanent magnet used for an undulator that generates radiation light by meandering electrons that travel in the first direction in which one end surface in the first direction forms the first connecting surface connected to another undulator permanent magnet, N poles and S poles are alternately arranged in the first direction on one magnetic pole surface in a second direction orthogonal to the first direction, and thus a magnetic flux density distribution having a plurality of peaks is generated, and when the plurality of peaks are represented as the first to m-th peaks Pm (m is an integer of 1 or more) in order from the side of the first connecting surface, a magnitude of the first peak P1 is larger than a magnitude of the third peak P3, the other end surface in the first direction is the second connecting surface connected to another undulator permanent magnet, when the plurality of peaks are represented as the first to n-th peaks Qn (n is an integer of 1 or more) in order from the side of the second connecting surface, a magnitude of the first peak Q1 is larger than a magnitude of the third peak Q3, a direction of a magnetic flux density of the first peak P1 and a direction of a magnetic flux density of the first peak Q1 are opposite to each other, and one of the first connecting surface and the second connecting surface is a convex connecting part that is convex in the first direction, wherein a direction of a magnetic flux density of a first peak when viewed from the side of a connecting surface of the pair of magnets of a magnetic flux density distribution in the first direction of one undulator permanent magnet of the pair of magnets and a direction of a magnetic flux density of a first peak when viewed from the side of the connecting surface of a magnetic flux density distribution in the first direction of the other undulator permanent magnet of the pair of magnets are opposite to each other. ### Claim 26 (depends on 1) A radiation light generating device comprising an undulator, wherein the undulator is an undulator that generates radiation light by meandering electrons and includes a vacuum chamber having a passage therein through which the electrons pass in a predetermined direction; and a pair of magnet arrays that are arranged to face each other with the passage therebetween in the vacuum chamber, wherein each of the pair of magnet arrays includes on magnetic pole surfaces that face each other, magnetic poles that attract each other and are alternately arranged in the predetermined direction such that a magnetic flux density distribution having a plurality of peaks in the passage is generated, and a pair of magnets formed by connecting the undulator permanent magnets according to claim 1 on the first connecting surfaces, wherein a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of one undulator permanent magnet of the pair of magnets and a direction of a magnetic flux density of a first peak when viewed from the side of the first connecting surface of a magnetic flux density distribution in the first direction of the other undulator permanent magnet of the pair of magnets are opposite to each other.