nuclear principles in engineering ch5

nuclei above lead (Pb) are all stable and have very long half-lives

only the conservation of (mass-energy) is needed for a radioactive decay to exist

the probability that a radionuclide will decay in a unit time , is:

the count rate (R) is proportional to the activity

the level of radioactivity of a substance is halved after one half-life , and is reduced to one quarter after two half-lives

the percent of Ra (A=226 ) that will decay during a period of 1000 years if the half life is 1600 years . Is:

radioactivity is the ratio of nuclide activity to the total mass of the element present .

the rate of change of a daughter nuclide is equal to the rate of production minus the rate of decay

in secular equilibrium the decay constant of the parent is much longer than the decay constant of the daughter

after one half-life of the radioisotope ,half of the maximum activity is formed

when a nucleus has too many neutrons, it decays by emitting protons

alpha decay is common for light nuclei

beta-minus decay will occur if an atom of higher Z has a smaller mass

beta decay has a continuous energy spectrum

alpha decay has a discrete energy spectrum

the average energy for beta-plus decay is equal to (0.4 E-max)

beta-minus decay produces an electron and a neutrino that always accompanies the decay.

the Q-value of beta-decay is equivalent to the difference in mass between the parent nucleus and the sum of the daughter nucleus and B particle

when the neutron-proton ratio is too low , the nucleus emits a positron

positive Q-value for a decay means that its not possible

after the internal conversion or electron capture , the nucleus would only emit X-rays

the kinetic energy of an auger electron corresponds to the difference between the energy of the initial electron and the ionization energy of the emitted auger electron.

gamma decay precedes alpha and beta decays

primordial radioisotopes are produced due to human actions

cosmic radiation can exist in many forms, from high speed heavy particles to high energy photons and muons

we can determine the age of a certain matter from the known content of radiocarbon C-12