γ

γ

γ

γ

γγ

What is gamma radiation?

How are they produced?

Gamma rays in outer space

γγ

γUses of gamma rays

Comparison of Gamma with Alpha and Beta Rays

Gamma rays (γ)are electromagnetic waves similar to visible light. The biggest difference between them is that gamma rays have greater frequency and shorter wavelength. Gamma rays have a great deal of energy and they are deadly for living things. They are more energetic than alpha and beta rays. This causes them to penetrate paper and metal sheets easily. They can only be stopped by thick lead blocks.

Unlike alpha and beta radiation, gamma does not occur itself. It needs an initial radiation to be emitted. After parent nucleus emits (gives out) alpha and beta particles, daughter nucleus may still be energetically unstable (excited). Because of the tendency to have minimum energy, daugter nucleus emits a great deal of energy. This radiation is called gamma radiation. Apart from alpha and beta radiation gamma radiation does not cause a change either in atomic number or mass number.

Gamma rays are not only produced by decaying of radioactive materials. They are also produced in outer space by supernova explosions, neutron stars and black holes. These events cause gamma bursts (which is emitting high amount of gamma rays). We can not see gamma rays. If we were able to see gamma rays, then the objects in space that emit gamma rays would be the brightest ones.

Gamma rays are deadly for cells. Direct contact causes hair loss in body, falling of teeth, radiation burn, dying of blood cells, tiredness and death. But we use this for our advantage. As a medicine, focused gamma rays are used to eliminate cancerous cells. This is called chemotheraphy.

Neutron NumberProton NumberMass Number

EnergyPenetration

Nucleus Change

ALPHA BETA GAMMA

Paper (lowest) Metal sheet (medium)

ConstantMedium

Decreases by 4Decreases by 1

Lowest

Change Same

Decreases by 2 Increases by 1 ConstantDecreases by 2 Constant

ConstantHighest

Lead Block (highest)

+

+

+

+

+

+

-

-

-

-

-

AlphaGammaBeta

Negative Charge

Positive charge

Murat Zaimoğlu

10/U 960412