Nuclide Imaging: Planar Scintigraphy, SPECT, PET - Polytechnic ...

Radioactive Decay Law• N(t): the number of radioactive atoms at a given time• A(t): is proportional to N(t)• From above, we can derive• The number of photons generated (=number of disintegrations)during time T is•∆N=T∫0A(t)dt=dNA = − = λNdtλ :decay constantT∫0N(t)=A(t)=λN0eNA e0−λt0edt−λt−λt== λNN00e−λt(1 −e−λT)EL5823 Nuclear Imaging Yao Wang, Polytechnic U., Brooklyn 9