CHARGED PARTICLE BEAM ACCELERATION AND EXTRACTION METHOD AND APPARATUS USED IN CONJUNCTION WITH A CHARGED PARTICLE CANCER THERAPY SYSTEM

• US 20100006770A1
• Filed: 07/06/2009
• Published: 01/14/2010
• Est. Priority Date: 05/22/2008
• Status: Active Grant

• Current Assignee: Andrey Vladimirovich Balakin, Pavel Vladimirovich Balakin
• Original Assignee: Vladimir Balakin
• Inventors: Balakin, Vladimir
• Granted Patent: US 8,067,748 B2
• Time in Patent Office: Days
• US Class Current: 250/396.R
• CPC Class Codes: A61N 2005/1061 using an x-ray imaging system having a separate imaging source
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: H01J 3/14 Arrangements for focusing or reflecting ray or beam H01J3/02, H01J3/04 take precedence
• CPC Class Codes: H05H 13/04 Synchrotrons
• CPC Class Codes: H05H 7/10 Arrangements for ejecting particles from orbits

Abstract

The invention comprises a charged particle beam acceleration and optional extraction method and apparatus used in conjunction with charged particle beam radiation therapy of cancerous tumors. Novel design features of a synchrotron are described. Particularly, turning magnets, edge focusing magnets, concentrating magnetic field magnets, and extraction elements are described that minimize the overall size of the synchrotron, provide a tightly controlled proton beam, directly reduce the size of required magnetic fields, directly reduces required operating power, and allow continual acceleration of protons in a synchrotron even during a process of extracting protons from the synchrotron.

Claims

1. An apparatus for tumor therapy using charged particles, the charged particles accelerated by a rounded corner polygon synchrotron, said synchrotron comprising:

a center; and

a charged particle circulation beam path running;

about said center;

through straight sections; and

through turning sections,

wherein each of said turning sections comprises a plurality of bending magnets,

wherein at least two of said plurality of bending magnets further comprise a magnetic field focusing section, said focusing section comprising;

a geometry tapering from a first cross-sectional area to a second cross-sectional area, said second cross-sectional area comprising less than two-thirds of an area of said first cross-sectional area, said second cross-sectional area proximate said charged particle beam path.

2. The apparatus of claim 1, further comprising:

a first focusing edge;

a second focusing edge;

a third focusing edge; and

a fourth focusing edge,

wherein a first of said turning sections comprises a first bending magnet and a second bending magnet,

wherein said first bending magnets terminates on opposite sides with said first focusing edge and said second focusing edge,

wherein a first plane established by said first focusing edge intersects a second plane established by said second focusing edge beyond said center of said synchrotron,

wherein said second bending magnets terminates on opposite sides with said third focusing edge and said fourth focusing edge,

wherein a third plane established by said third focusing edge intersects a fourth plane established by said fourth focusing edge beyond said center of said synchrotron,

wherein all of said first focusing edge;

said second focusing edge;

said third focusing edge; and

said fourth focusing edge bend the charged particles toward said center of said synchrotron.

3. The apparatus of claim 2, wherein said circulation beam path comprises a length of less than sixty meters, and wherein a number of said straight sections equals a number of said turning sections.

4. The apparatus of claim 3, wherein said geometry carries a magnetic field during use, wherein the magnetic field concentrates in density from said first cross-sectional area to said second-cross-sectional area.

5. The apparatus of claim 4, wherein said second cross-sectional area comprises a flat surface, said flat surface comprising about a zero to three micron polish.

6. The apparatus of claim 1, wherein said turning sections each comprise at least four bending magnets, said four bending magnets comprising at least eight edge focusing surfaces, wherein geometry of said edge focusing surfaces focuses the charged particles in said charged particle circulation beam path during use.

7. The apparatus of claim 1, wherein each of said turning sections turns the charged particles by about ninety degrees.

8. The apparatus of claim 7, wherein each of said turning sections comprises at least four focusing edges, wherein geometry of said focusing edges yield an edge focusing effect on the charged particles.

9. The apparatus of claim 8, said bending magnets comprising a tapered core, said tapered core comprising a first cross-section distance at least one and a half times longer than a second cross-section distance, said second cross-section distance proximate a gap, said gap having a surface polish of less than about ten microns roughness, said charged particle circulation beam path running through said gap.

10. The apparatus of claim 1, wherein said number of turning sections comprises exactly four turning sections, wherein each of said four turning sections turns the charged particle circulation beam path about ninety degrees, said synchrotron capable of accelerating the charged particles to at least 300 MeV.

11. The apparatus of claim 10, wherein said four turning sections comprise at least thirty-two charged particle edge focusing surfaces.

12. The apparatus of claim 1, wherein said turning sections comprise at least eight bending magnets, wherein said charged particle circulation beam path does not pass through any operational quadrupole magnets.

13. The apparatus of claim 1, each of said turning magnets comprising:

a gap, said charged particle beam path running through said gap, and

a core, wherein said core terminates at said gap with a surface comprising a finish of less than about ten microns polish.

14. The apparatus of claim 13, further comprising:

an extraction control algorithm, said extraction control algorithm receiving input generated by a current originating at an extraction foil, said extraction foil proximate said charged particle circulation beam path, said extraction control algorithm comparing a feedback input to an irradiation plan, said extraction control algorithm adjusting a radio-frequency field in a radio-frequency cavity system.

15. The apparatus of claim 1, wherein at least one of said turning magnets further comprises:

a gap through which said charged particle circulation beam path runs; and

an amplifier geometry, wherein said amplifier geometry concentrates a magnetic field approaching said gap.

16. The apparatus of claim 1, further comprising:

a winding coil, wherein a turn in said coil wraps around at least two of said turning magnets, wherein said turn does not occupy space directly between said at least two of said turning magnets.

17. The apparatus of claim 1, wherein said synchrotron further comprises:

an extraction material;

at least a one kilovolt direct current field applied across a pair of extraction blades; and

a deflector,

wherein the charged particles pass through said extraction material resulting in reduced energy charged particles,

wherein the reduced energy charged particles pass between said pair of extraction blades,

wherein the direct current field redirects the reduced energy charged particles out of said synchrotron through said deflector, and

wherein said deflector yields an extracted charged particle beam.

18. A method for tumor therapy using charged particles, the charged particles accelerated by a rounded corner synchrotron, said method comprising the step of:

accelerating the charged particles in a charged particle circulation beam path running about a center of said synchrotron, said charged particle circulation beam path comprising;

straight sections; and

turning sections, wherein each of said turning sections comprises a plurality of bending magnets; and

focusing the charged particles using at least two of said plurality of bending magnets that further comprise a magnetic field focusing section, said focusing section comprising;

a geometry tapering from a first cross-sectional area to a second cross-sectional area, said second cross-sectional area comprising less than two-thirds of an area of said first cross-sectional area, said second cross-sectional area proximate said charged particle beam path, wherein said geometry carries a magnetic field during use, wherein the magnetic field concentrates in density from said first cross-sectional area to said second-cross-sectional area.

19. The method of claim 18, further comprising the step of:

bending the charged particles toward said center of said synchrotron using all of a first focusing edge, a second focusing edge, a third focusing edge, and a fourth focusing edge,

wherein a first of said turning sections comprises a first bending magnet and a second bending magnet,

wherein said first bending magnets terminates on opposite sides with said first focusing edge and said second focusing edge,

wherein a first plane established by said first focusing edge intersects a second plane established by said second focusing edge beyond said center of said synchrotron,

wherein said second bending magnets terminates on opposite sides with said third focusing edge and said fourth focusing edge, and

wherein a third plane established by said third focusing edge intersects a fourth plane established by said fourth focusing edge beyond said center of said synchrotron.

20. The method of claim 19, wherein said circulation beam path comprises a length of less than sixty meters, and wherein a number of said straight sections equals a number of said turning sections.

21. The method of claim 20, wherein said second cross-sectional area comprises a flat surface, said flat surface comprising about a zero to three micron polish.

22. The method of claim 18, further comprising the step of:

focusing the charged particles in said charged particle circulation beam path during use with edge focusing surfaces having focusing geometry, wherein said turning sections each comprise at least four bending magnets, said four bending magnets comprising at least eight surfaces having said focusing geometry.

23. The method of claim 18, further comprising the step of:

turning the charged particles about ninety degrees with each of said turning sections.

24. The method of claim 23, wherein each of said turning sections comprises at least four focusing edges, wherein geometry of said focusing edges yield an edge focusing effect on the charged particles.

25. The method of claim 24, said bending magnets comprising a tapered core, said tapered core comprising a first cross-section distance at least one and a half times longer than a second cross-section distance, said second cross-section distance proximate a gap, said gap having a surface polish of less than about ten microns roughness, said charged particle circulation beam path running through said gap.