Method and system for operating electron guns in magnetic fields
US9099271B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2012 |
| Grant date | Aug 4, 2015 |
| Priority date | — |
| Expiry date | Sep 14, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H2007/084
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of configuring an electron gun for generating and injecting an electron beam into a linac accelerating waveguide operating in magnetic fringe fields of an MRI scanner in the absence of a magnetic shield is provided using an appropriately programmed computer to determining an anode drift tube diameter at an injection point of a linac according to a magnetic field value from an MRI scanner and to a predetermined current density, where the magnetic field has an isocenter, determining a transverse diameter of a Type M cathode in an electron gun, according to the anode drift tube diameter and the current density, and minimizing an emittance value in an electron beam of the electron gun at an entry point of the anode drift tube by optimizing the distance between the cathode and the anode, where the electron beam is along an axis of symmetry of the magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.