During beta radiation, a neutron decays into a proton in a nucleus, releasing the beta particle and an antineutrino.

1.       Gamma Radiation

·        Gamma rays are high energy electromagnetic rays.

·        It has no mass and no charge.

·        It occurs after the nucleus has emitted either alpha or beta radiation.

·        No new atom is formed when gamma rays are emitted.

Deflection of Radiation in an Electric field:

·     Alpha particles are attracted to the negative terminal. 

·     Beta particles are attracted to the positive terminal. They are so light that they get deflected more than alpha particles.

·     The gamma rays are unaffected by the field.

Penetrating Power of radiations:

·        The alpha particle is the shortest in range. It is weakly penetrating. Typically alpha particle can be stopped with a sheet of paper (or skin).

·        The high energy electron of beta radioactivity is moderately penetrating. The electrons can often be stopped with a few centimeters of metal.

·        The electromagnetic gamma ray is extremely penetrating, even penetrating considerable thicknesses of concrete.

http://www.youtube.com/watch?v=N8JRqW1-my4&NR=1

http://www.youtube.com/watch?v=kaS11fW7nNc&feature=related

Ionising Power of radiations:

·        So it is not suitable for radiation therapy. Because of the particle's relatively high charge, it is heavily ionizing and will cause severe damage if ingested.

• It is less ionizing than alpha radiation, but more than gamma. The radiation hazard from betas is greatest if they are ingested.
• It is weakly ionizing.

Summary of the nature of alpha, beta and gamma radiations:

      The alpha decay was seen only in heavier elements (atomic number 52 and greater). The other two types of decay, the beta decay and the gamma decay were seen in all of the elements.

         http://www.youtube.com/watch?v=crtTQOeUJYU&feature=related

Nuclear Changes due to Radioactive Decay:

·        Alpha decay:-

Atomic number decreases by two

Atomic mass decreases by four.

Example 1:

Uranium-238 which has an atomic number of 92 and an atomic mass of 238 will decay to Thorium-234 which has an atomic number of 90 and an atomic mass of 234 with the emission of an alpha particle.

 Example 2:

 Americium-241 which has an atomic number of 95 and an atomic mass of 241 will decay to Neptunium-237 which has an atomic number of 93 and an atomic mass of 237 with the emission of an alpha particle. The equation would look like this:- 

•     Beta decay:-

Atomic number increases by one

Atomic mass unchanged

Example 1:

Thorium-234 undergoes decay and forms Protactinium-234.

 Example 2:

Strontium-90 undergoes decay and forms Yttrium-90.

Atomic mass unchanged.

      So no new atom is formed when gamma rays are emitted.

Summary of Changes due to Radioactive Decay:

A nucleus with mass number A and atomic number Z is represented as (A, Z). Radioactive decay results in an atom of one type, called the parent nuclide transforming to an atom of a different type, named the daughter nuclide.

The column "Daughter nucleus" indicates the difference between the new nucleus and the original nucleus.