alpha is a helium nucleus , atomic mass of 4, charge is 2 , short penetration , absorbed by cells , highest ionisation density
beta is a fast moving electron , charge is -1 , penetrates a few meters, can pass cells
gamma is a high frequency EM wave, unlimited penetration , unlikely to pass through cells
ioisation is an atom gaining or losing an electron to become an ion
ionisation density is when a particle loses energy by the medium absorbing it
beta used to detect blood clots and gamma is used for tracers
fission is when a large nucleus is broken into 2 smaller nuclei releasing energy and neutrons
fission is spontaneous
fusion is 2 small nuclei fusing to create a larger nucleus
fission chain reaction- neutrons produce additional fission to atleast one other nucleus
fission is used in nucllear power stations to produce energy
fusion requires high temperatures so plasma containment is used instead
absorbed dose is the radiation energy absorbed per kilogram of mass
equivelant dose is the biological harm caused by radiaion
the limit for the public is 2.2msv and the limit for a worker is 20mSv
activity is the number of nuclear decays per second
background radiation from gas in the ground/ rocks/ cosmic microwaves
to measure activity measure the background radiation for 1 inute then record record source radiation at each subsequent minute and subtract background radiation
half life is the time taken for activity to fall by half
to measure half life measure the count at set time intervals the count at regular intervals and subtract background radiation