# nuclear physics, ju, second semester, 2010-2011 (saed dababneh). 1 radioactivity

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• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*RadioactivityNatural decay seriesOther 2?HW 10

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity decay constant.Compare to human life time!!!

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Show that the mean lifetime . N is difficult to measure. Instead, measure N number of decays between t and t +t:

If t

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*RadioactivityHW 11KraneProblem 6.1 Activity measured in units of becquerel (Bq) = 1 decay/s. 1 curie (Ci) = 3.7 x 1010 Bq. Activity is not dose!!!!!

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*RadioactivityExponential decay of species 1 and exponential growth of species 2.Isotope 1 (initial number N0) decays into stable isotope 2.

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity If parent nucleus decays by two modes:Derive.

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity If radioactive species 1 is produced in a reactor or accelerator with rate R.ProductionDecayShow thatand thussecular equilibriumalmost linearHW 12

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity How long should we irradiate? Activity per cost?

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity If species 2 is radioactive. Possible also that species 3 is radioactive. 1 2 3 4 .. until we reach a stable isotope. But for now let us consider species 3 to be stable. For the parent nucleus assume that N1(t=0)=N0. For the daughters assume that N2(t=0) = N3(t=0) = 0. Verify the following:What if 2 = 0?What if 1 is very small? N1(t) = ?

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Secular equilibrium 1 is very small (1
• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity Transient equilibrium If 1 is smaller than 2 (1 < 2), show that

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity As t increases,

but the activities themselves are not constant.

230Th decays, in effect, with the decay constant of 234U. Parallel !?

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity Discuss the case when 1 is larger than 2 (1 > 2).

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

• Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).*Radioactivity In general, 1 2 3 4 .. until we reach a stable isotope.

If N0 of type 1 and N2(t=0) = N3(t=0) = = 0 Bateman equations.Exclude the term (k - k).

Nuclear Physics, JU, Second Semester, 2010-2011(Saed Dababneh).

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