Radiotherapy device

Patent metadata

Field	Value
Publication number	US-2023019382-A1
Application number	US-202017757680-A
Country	US
Kind code	A1
Filing date	Dec 18, 2020
Priority date	Dec 19, 2019
Publication date	Jan 19, 2023
Grant date	—

Abstract

A particle accelerator comprising a waveguide comprising a series of acceleration cells. The series of acceleration cells comprise an input acceleration cell configured to accelerate a beam of electrons along the central axis of the cells. A source of electrons is configured to input a beam of electrons into the input acceleration cell and a magnet arrangement is configured to prevent electrons that have deviated from the beam of electrons from hitting the source of electrons.

First claim

1 . A particle accelerator comprising:
a waveguide comprising a series of acceleration cells, wherein the series of acceleration cells includes an input acceleration cell, configured to accelerate a beam of electrons along a central axis of the cells; a source of electrons configured to input a beam of electrons into the input acceleration cell; and a. magnet arrangement configured to prevent one or more electrons that have deviated from the beam of electrons from colliding with the source of electrons.

2 . The particle accelerator of claim 1 , wherein the magnet arrangement is configured to redirect the one or more electrons that have deviated from the beam of electrons back towards the beam of electrons.

3 . The particle accelerator of claim 1 , wherein the input acceleration cell has a first end and a second end, and wherein the magnet arrangement is located at the first end of the input acceleration cell.

4 . The particle accelerator of claim 1 , wherein a nozzle of the source of electrons is configured to output electrons into the input acceleration cell, and wherein the magnet arrangement is located at the nozzle.

5 . The particle accelerator of claim 1 , wherein the magnet arrangement is located at an intersection between the source of electrons and the input acceleration cell.

6 . The particle accelerator of claim 3 , wherein the magnet arrangement is configured as a ring around the first end of the input acceleration cell.

7 . The particle accelerator of claim 1 , wherein the magnet arrangement includes an alpha magnet, the alpha magnet comprising:
an entrance point configured to receive electrons travelling in a first direction; and a magnetic field of increasing strength in a direction away from the entrance point, such that the received electrons travel along a beam path and exit the magnet arrangement at the entrance point travelling in a second direction.

8 . The particle accelerator of claim 7 , wherein the second direction is angled at 270 degrees to the first direction.

9 . The particle accelerator of claim 7 , wherein the magnet arrangement further includes a second alpha magnet, wherein the second alpha magnet is positioned to receive electrons from the first alpha magnet, and wherein the first alpha magnet is angled at 90 degrees to the second alpha magnet.

10 . The particle accelerator of claim 1 , wherein the source of electrons is positioned at a location that does not lie along the central axis of the acceleration cells.

11 . The particle accelerator of claim 1 , further comprising:
a source of electromagnetic radiation configured to supply electromagnetic radiation to the waveguide to accelerate the beam of electrons.

12 . The particle accelerator of claim 1 , further comprising:
a target, wherein the target is configured to be struck by the beam of electrons and produce radiation.

13 . A radiotherapy device comprising:
a particle accelerator, the particle accelerator including:
a waveguide comprising a series of acceleration cells, wherein the series of acceleration cells comprises an input acceleration cell, configured to accelerate a beam of electrons along a central axis of the cells;
a source of electrons configured to input a beam of electrons into the input: acceleration cell; and
a magnet arrangement configured to prevent one or more electrons that have deviated from the beam of electrons from colliding with the source of electrons.

14 . A method for use in a particle accelerator, the method comprising
producing a beam of electrons from a source of electrons; inputting the beam of electrons into an input acceleration cell of a waveguide; applying an RF field to the waveguide to create an oscillating electric field along a central axis of the waveguide to accelerate the beam of electrons along the central axis; and trapping electrons that have deviated from the beam of electrons using a magnet arrangement.

15 . The method of claim 14 , further comprising:
activating the magnet arrangement to trap the electrons that have deviated from the beam of electrons.

16 . The method of claim 15 , further comprising:
deactivating the magnet arrangement to allow the trapped electrons to join the beam of electrons.

17 . The method of claim 16 , wherein deactivating the magnet arrangement is timed to coincide with a phase change of the RF field applied to the waveguide.

18 . A particle accelerator arranged to receive a beam of electrons, comprising:
a waveguide including a series of acceleration cells, wherein the series of cells includes an input acceleration cell; a source of electrons configured to input electrons into the input acceleration cell; and a diversion channel configured to remove electrons from the waveguide that are traveling towards the source of electrons.

19 . The particle accelerator of claim 18 , wherein the diversion channel is further configured to remove electrons from the input acceleration cell.

20 . The particle accelerator of claim 18 , wherein the diversion channel is located an intersection between the source of electrons and the input acceleration cell.

21 . The particle accelerator of claim 18 , wherein the diversion channel is connected to a secondary particle accelerator that is configured to accelerate a secondary beam of electrons.

22 . The particle accelerator of claim 21 , wherein the diversion channel, the secondary particle accelerator, and the secondary beam of electrons are used for patient imaging.

Assignees

• Elekta ltd

Inventors

• Doherty Peter
• Woolridge Emma
• Shinton Ian

Classifications

• H05H9/04

  Standing-wave linear accelerators · CPC title

• H05H2007/122

  by electromagnetic means, e.g. RF cavities · CPC title

• H05H7/08 Primary

  Arrangements for injecting particles into orbits · CPC title

• H05H9/048 Primary

  Lepton LINACS · CPC title

• H05H2007/043

  for beam focusing · CPC title