Linear Accelerator

The linear accelerator is also known as a linear particle accelerator. It comes in use in the field of medicine and therapeutic applications as it generates electrons and X-rays of high energy. They can generate high kinetic energy. It is ideal for protons and electrons in particle physics for getting high kinetic energy.

Introduction to Linear Accelerator

It is a kind of particle accelerator that enhances the kinetic energy of charged ions or subatomic particles. The charged particles are subjected to oscillating electric potential with a linear beam line. The ionizing radiation functions by damaging DNA cells like cancer cells.

Though Linear Accelerator was invented in 1930, it took over 4 decades for the Linear particle accelerator to come into existence. Created by Stanford professor Dr Peter Fessenden in 1972, the main purpose of the accelerator was to be able to combine X ray and electron treatment under one specific instrumentation. His core subject of study was to understand the usability of two different type of radiations in the treatment of Tumors.

Working Principle of a Linear Accelerator

Linear accelerator works using microwave technology to initiate the electron response. The electrons collide with metal iodes to cause a chain reaction that results in the formation of high energy x-rays.

Further, the source of ion provides an electron bunch that accelerates to either drift tube of positive and negative potential. The RF source shifts the polarity when electrons enter the tube. Moreover, the first tube negatively charges while the second drift tube gets a positive charge.

After that, the electron comes outside due to inertia. At this instance, the electrons move with the first drift tube and attract by another in the same direction.  The accelerated electrons have high velocity and travel at long distances. Hence, the drift tube should be long when the electron comes close to the target due to high velocity.

Further, the main reason for the development of the linear accelerator is to deliver high energy rays at a target-specific location.  Thus the high velocity electron emerging from the drift tube an be easily directed towards the specific source or tumour using the gantry of the drift tube.

Components of the Linear Accelerator

• Electron generation component- Generate and guide electrons in accelerating wave guide.
• Beam transport- Move electrons to target
• Electron acceleration component- accelerate electrons
• Flattering filter, collimation, and ionization chamber- modify beam before application.
• Pulse modulator- Generate timed energy pulse to electron gun and RF generator.
• Radiofrequency generator- Produces electromagnetic waves
• Control panel- it is the panel that manages the function of the linear accelerator.

Application of a Linear Accelerator

Many oncologists recommend volume and dosage to patients. Further, the medical physicist decides the time and amount of dosage and calculates acceleration time.  However, different industries have wide usage of Linear accelerator with a distinct purpose.

• LINAC synchrotron injector- It is the initial stage for a high energy accelerator.
• Boron Neutron Capture Therapy- Nuclear reactors come in use traditionally as a neutron source. LINAC sources offer a controlled spectrum of the neutron. It generates less radioactive waste.
• Isotope production- It is perfect for generating PET isotopes.

Safety Assurance while using Linear Accelerator

LINAC machines come in use for treating cancer and generate high radioactive energy. Moreover, this device can harm patients.  Radio oncologists plan proper treatment as per the medical report. Further, the plan is made with the radiation physicist. Tracker is a device that checks the proper working of the machine, radiation intensity, and velocity.

FAQ on Linear Accelerator

Question 1: What is the working principle behind a Linear Accelerator?

Answer 1: We refer to the Linear Particle Accelerator as LINAC also. It is one of the variants of Particle Accelerator that uses oscillating electric potential through a linear beam to accelerate the charge of a subatomic particle.

Question 2: What does linear Acceleration mean?

Answer 2: In a specified given time frame if there is a change in the velocity of any object moving in a straight line, then the acceleration will also increase. Thus, on the basis of this, the increasing or decreasing velocity, the rate of acceleration will also increase or decrease accordingly. Thus, we refer to this as Linear Acceleration.

Question 3: What are the  different types of Particle accelerators?

Answer 3: Particle Accelerator are of 2 types

1. Linear Particle accelerator directs the movement of a particle in the direction of the straight or linear beam line.
2. Circular Particle Accelerator directs the movement of particles along a circular track line.