Wondering what Cosmic Radiation & Cosmic Ray Showers are and how these are formed? If you are, you are at the perfect place.
Cosmic radiation and cosmic ray showers are some of the most intriguing and fascinating phenomena in the universe. While the term “radiation” may have negative connotations, cosmic radiation is a natural occurrence that has existed since the beginning of time.
In this comprehensive guide, I will take you into cosmic radiation and cosmic ray showers, their effects on Earth and beyond, and how scientists study these phenomena.
Cosmic Rays or Cosmic Radiation
Soon after 1900, it was shown by scientists that the air in an ionization chamber, which was completely protected against penetration of α, β and γ rays by surrounding it with thick lead walls, was still conductive; and it was thought that the inns causing this conductivity were produced by some rays coming from an unknown source.
In 1911, Hess and Kolhoster, by placing ionization chambers in balloons and sending them to great heights, established the existence of penetrating radiations coming from above. These radiations are called Cosmic Rays.
- Cosmic radiation refers to high-energy particles that originate from outer space.
- These particles can come from a variety of sources, including the sun, other stars, and distant galaxies.
- The majority of cosmic radiation is made up of protons, but it can also include electrons, alpha particles, and other particles.
- Cosmic radiation is constantly bombarding the Earth’s atmosphere, but our planet’s magnetic field and atmosphere protect us from the harmful effects of this radiation.
Improvements of Physics of Cosmic Radiations: East West Effect
Millikan began further investigations on these rays in 1925 by means of sounding balloons carrying a recording electroscope, thermometer and barometer; and also by lowering measuring instruments deep into lakes.
It was found that the intensity of the penetrating rays (i.e., Cosmic Rays) increases with height, reaching a maximum at height, equivalent to 9 meters of water above the earth, which shows that most of the rays must actually be produced there, and much of the cosmic radiation observed at the lower level is secondary radiation, produced by the impact of the original radiation with air molecules.
It has also been noticed that the intensity of cosmic rays is greater for higher magnetic latitudes than for lower latitudes. This seems to be due to the fact that the magnetic field of the earth deflects the cosmic ray particles, although some of them are still able to reach the earth, while others do not.
Also, the number of particles coming from the west is greater than from the east, and the effect is known as The East-West Effect.
Types of Cosmic Radiations
Cosmic radiations are of two types:
Those which penetrate about 10 cm of lead are called Hard Cosmic Radiations and those which are absorbed within this thickness of lead are soft.
The great penetrating power of the cosmic rays was at first believed to show that the rays must be photons of the same nature as γ rays. In 1926, Bothe and Kolhoster showed that the cosmic rays consist largely of electrically charged particles and the primary or original cosmic rays consist of α particles, protons and electrons.
Cosmic Rays made it happen! Discovery of Positron
In 1932 Anderson used Wilson’s cloud chambers and powerful magnetic fields to bend the path of the cosmic ray particles. He discovered that there was present a new type of particle, which has the same mass as an electron but has a positive charge equal to that of an electron.
Do you know?
A photon can be broken into an electron and a positron. This process is called Pair Production.
Cosmic Ray Showers
When cosmic rays enter the Earth’s atmosphere, they collide with atoms and molecules in the air, creating a cascade of secondary particles. This cascade of particles is known as a cosmic ray shower. The secondary particles can include electrons, muons, and other particles. These cosmic ray showers can occur anytime, but they are more common during solar storms and other periods of increased solar activity.
Scientists study cosmic ray showers using various methods, including ground-based detectors, balloons, and satellites. Ground-based detectors measure the flux and energy of cosmic ray particles at different locations on Earth. Balloons and satellites are used to study cosmic rays outside of the Earth’s atmosphere. These methods have allowed scientists to understand better the origins and effects of cosmic radiation and cosmic ray showers.
Many times cosmic rays have been investigated through Wilson cloud chambers and tracks due to secondary radiations that have been obtained. Their tracks show that they originate from the same point, and many good-ring particles emanate from the same point. Such a group of particles forms a shower, a Cosmic Shower.
A theoretical explanation of their showers has been given by Dr. Homi Bhabha & Heitler.
It is assumed that the shower producing raw is a fast moving electron. When it passes close to the nucleus of an atom at A (see image), a photon radiated which consequently passes close to the nucleus of another atom as at B and produces a +ve & a -ve electron, i.e., a positron and a negatron(electron). Meanwhile the original electron produces another photon at C, which in turn produces another electron pair at D and so on, thus producing fresh chains, constituting what is known as the Cascade Process. This process continues so long as the energy of the electron and photon is greater than a critical value & performes showering.
Note that A, B, C, D…are nuclei. And a high energy γ ray / photon passing close to the nucleus of an atom is annihilated and electrons/positrons are produced.
Effects of Cosmic Radiation
While cosmic radiation is generally harmless to humans on the ground, it can pose a risk to astronauts and airline crews who are exposed to higher levels of radiation. Long-term exposure to cosmic radiation can increase the risk of cancer, cataracts, and other health issues. Cosmic radiation can also interfere with electronics and communication systems, which is why space missions and airline flights must consider the effects of cosmic radiation.