Electron linear accelerator (Electron LINAC) is a type of charged particle accelerator that uses high microwave power to establish a longitudinal electric field in a traveling wave or standing wave acceleration structure to accelerate an electron beam. The following is a detailed introduction about electron linear accelerators:

1、 Basic Overview

Definition: An electron linear accelerator accelerates an electron beam through a microwave electromagnetic field to obtain high energy.

Type: According to the type of microwave, electron linear accelerators can be divided into traveling wave type and standing wave type.

Energy and power: The electron energy of an electron linear accelerator is generally high (greater than 5MeV), with an output power ranging from a few kW to several tens of kW. Due to the limitations of industrial radiation safety, the maximum energy of industrial irradiation electron linear accelerators is usually set at 10 MeV.



2、 Structural principle

Basic structure: The electron linear accelerator can be designed as a standing or horizontal accelerator according to the requirements of the irradiation process. It mainly consists of an electron gun, an accelerator tube, a focusing coil, a microwave power source (magnetron or klystron), a pulse modulator, a microwave transmission system, etc.

working principle:

Electron gun: operates in a pulsed state, and is designed to inject electron beam energy, pulse current intensity, beam diameter, and divergence angle into the acceleration tube as needed.
Acceleration tube: consisting of a focusing section and an acceleration section, using constant temperature water cooling measures to ensure stable operation parameters of the electron beam.
Focusing coil: Set according to the beam envelope focusing requirements in theoretical calculations to maintain the focused state of the electron beam.

Microwave power source: using magnetron or klystron to accelerate electrons as needed and provide energy.

Pulse modulator: provides the required pulse high voltage for magnetron or klystron.

Microwave transmission system: Transmit microwave power into the accelerating tube to accelerate the electron beam.

3、 Application Fields

The application range of electron linear accelerators is very wide, covering multiple fields:

High energy physics: used for building high-energy physics experimental devices such as positron electron colliders.

Industry: Used for industrial inspection, irradiation processing, etc.

Medical and Health: Medical electronic linear accelerators have been widely used in hospitals to eliminate or reduce tumors by generating high-energy radiation to irradiate tumor tissues.
Other: It is also applied in many fields such as agriculture (breeding of high-quality seeds, etc.), materials science, food industry (food irradiation processing, etc.), environmental governance, national defense (container inspection, etc.)


4、 Medical electronic linear accelerator

The working principle of a medical linear accelerator is to establish an electromagnetic field inside the accelerator tube. After electron injection, it continuously accelerates and emits high-energy radiation at a speed close to the speed of light. These rays irradiate tumor tissue, damaging the DNA of cells through ionizing radiation, causing the cells to lose their proliferative ability, thereby achieving the goal of killing tumor cells. Medical electronic linear accelerators are mainly composed of radiation heads, kV and MV imaging systems, treatment beds, and other auxiliary systems. They have multiple treatment modes and image guidance functions to improve the accuracy and effectiveness of treatment.


In summary, the electron linear accelerator is an important charged particle accelerator with broad application prospects and significant scientific value. With the continuous advancement and development of technology, the performance and functionality of electron linear accelerators will continue to improve and perfect.