The Fundamentals of Nuclear Physics Part one BME College Sherman sheen The Physics of Radiology

The Fundamentals of Nuclear PhysicsPart one

BME College Sherman sheen

The Physics of Radiology

Natural RadioactivityGeneral state of particles

Continual motionUncertainty for a single particle

Statistical rules in radioactive nucleus some certain percentage

Stable atom when Z<82

Artificial RadioactivityHigh energy devices

produce new particles artificially

How to detect the new conversion Geiger counter or scintillation counter chemical separation

Activity

NtNA

Definition: the number of disintegrations per unit time

λ transformation constant

hhh tttttt AeAeNA /0

/693.00

/693.00 2/

Initial activity = A0 = N0λ =ht

N 693.00

Activity

Unit: becquerel1 Bq = 1 disintegration per second

1 curie (Ci) = 3.700×1010 Bq

the number of disintegrations per second from 1 gram of radium

Activity

Decay of the activity of a 198Au source containing 108 atoms

thousands of curies (~1014 Bq) --therapy machines

Activity

Generally speaking

mCi (~108 Bq) ------ diagnostic procedures