Alpha vs Beta vs Gamma Particles: Difference and Comparison

Key Takeaways

1. Composition: Alpha particles consist of two protons and two neutrons. Beta particles are high-energy electrons. Gamma rays are high-frequency electromagnetic waves.
2. Origin: Alpha and beta particles originate from radioactive decay of unstable atomic nuclei. Gamma rays are released as excess energy from nuclear reactions.
3. Penetrating Power: Alpha particles have low penetrating power and can be stopped by skin or paper. Beta particles can pass through flesh but are stopped by aluminum. Gamma rays have very high penetration through most materials.

What is Alpha Particle?

An alpha particle is formed with two protons and two neutrons. It creates a helium nucleus. The symbol of alpha is α. It is large compared to other subatomic particles. 

Alpha particles can ionize many other atoms as they pass through matter due to their strong ionizing effect. During alpha decay, a radioactive decay process, alpha particles are radiated.

The penetrating power of alpha particles has limited penetrating power and can be easily stopped by a few centimeters of air. These particles are capable of damaging living tissues and causing health risks. Fields such as radiation therapy and nuclear physics study alpha particles.

What is Beta Particle?

A beta particle can be an electron (β-) or a positron (β+). Beta decay radiates beta particles. During this process, an unstable atomic nucleus undergoes a transformation and emits beta particles.

The mass of beta particles appears to be low when compared to alpha particles. But its speed is higher. It is almost equal to the speed of light speed.

These can be the reason for the excitation of atoms during the interaction due to their moderate ionizing power. Medical imaging and radiation therapy have applications for beta particles. However, they can be harmful if proper shielding and safety are not taken.

What is Gamma Particle?

Gamma particles are photons that possess no mass and no electric charge. Nuclear fusion or radioactive decay causes these particles. Its penetration power is much stronger than alpha or beta particles. 

Gamma rays are very harmful and can be stopped using thick shielding of lead or concrete. However, they come with some benefits too. They can be used in cancer treatment, industrial testing, and sterilization.

Difference Between Alpha, Beta, and Gamma Particles

1. Alpha particles are emitted during alpha decay, while beta particles are given out during beta decay processes. At the same time, gamma particles are produced during radioactive decay or other high-energy processes such as nuclear reactions.
2. Alpha particles comprise two protons and two neutrons, whereas beta particles are either electrons (beta-minus) or positrons (beta-plus), and gamma particles are not particles but high-energy photons.
3. Alpha particles have the highest mass because they carry two protons and two neutrons. Beta particles have negligible mass, and gamma particles, being photons, have no mass.
4. The speed of traveling of alpha is relatively slow. But beta particles can attain higher rates, which get closer to the speed of light. On the other hand, gamma particles travel at the speed of light as they are photons.
5. The shielding requirements of the three particles are different, too. Alpha particles can get stopped by centimeters of air or paper, while in the case of beta particles, the requirement is aluminum or plastic. Gamma particles can be prevented with thick lead or concrete.

Comparison Between Alpha, Beta, and Gamma Particles

Parameter of Comparison	Alpha Particle	Beta Particle	Gamma Particle
Charge	Its charge is +2.	Its charge is -1 (electrons), +1 (positrons).	Its charge is 0.
Mass	Its mass is relatively large	Its mass is negligible.	This is massless.
Ionizing power	Its ionizing power is high.	Comparatively, it has lower ionizing power.	Among the three, its ionizing power is the lowest.
Penetration power	Its penetration power is low.	It has a higher penetration power comparatively.	Its penetration power is the highest.
Speed	Its speed is relatively slow.	It has a higher speed than alpha particles but lower than gamma particles.	It has the speed of light.

References

1. https://books.google.com/books?hl=en&lr=&id=3CVyS-qQL6UC&oi=fnd&pg=PP1&dq=Difference+Between+Alpha,+Beta+and+Gamma+Particles&ots=9EIfFikPnx&sig=X09IsZ1UyPNQo4DJFOs0aK-Kh4s
2. https://ieeexplore.ieee.org/abstract/document/6825905/
3. https://www.jstor.org/stable/15205

Last Updated : 01 October, 2023