Muons

What do you understand by the term “Muon”?

Answer: Muons are subatomic particles raining from space, they are created when the particles in Earth’s atmosphere collide with cosmic rays.

Enrich your learning:

About Muons:

• Muon is one of the fundamental subatomic particles, the most basic building blocks of the universe.
• These particles resemble electrons but are 207 times as massive.
• The muons that hit the Earth result from particles in the Earth’s atmosphere colliding with cosmicrays.
  • Cosmic rays are high-energy protons and atomic nuclei that move through space at just below the speed of light.
• Muons exist for only 2.2 microseconds before they decay into an electron and two kinds of neutrinos.
• As they move at nearly the speed of light, muons travel far before decaying.
• These particles constantly hit the Earth’s surface and pass through almost any substance.
  • About 10,000 muons reach every square metre of the Earth’s surface a minute.
• They do not stop until they penetrate far below the surface of the Earth.

About Muon tomography or Muography:

• Muography is conceptually like X-ray but capable of scanning much larger and wider structures due to penetration power of muons.
• As these high-energy particles are naturally produced and ubiquitous, a muon detector is needed within or near the object of interest for detection.
• Detector tracks the number of muons going through the object from different directions, to form a three-dimensional image.

Applications:

• Muons can help detect dangerous nuclear material and see into damaged nuclear power plants.
• Used for archeological purposes to peer inside large, dense objects such as the pyramids in Egypt.

Why in News?

Researchers are examining the fortress wall of Xi’an, an ancient city in China, by using tiny outer space particles, muons, that can penetrate hundreds of metres of stone surfaces.