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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Jagdish K. Tuli NNDC Brookhaven National Laboratory Upton, NY 11973, USA Decay Scheme Normalization
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 1.Relative intensity is what is generally measured 2. Multipolarity and mixing ratio ( ). 3. Internal Conversion Coefficients Theoretical Values: From BRICC
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Experimental values: For very precise values ( 3% uncertainty). E = 661 keV ; 137 Cs ( K =0.0902 + 0.0008, M4) Nuclear penetration effects. 233 Pa - decay to 233 U. E = 312 keV almost pure M1 from electron sub-shell ratios. However K (exp) = 0.64 + 0.02. ( K th (M1)=0.78, K th (E2)=0.07)
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 For mixed E0 transitions (e.g., M1+E0). 227 Fr - 227 Ra E = 379.1 keV (M1+E0); (exp) = 2.4 + 0.8 th (M1) = 0.40; th (E2) = 0.08 675.8 296.6 379.5 ½- <10 ps 227 Ra
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Decay Scheme Normalization Rel. Int.Norm. FactorAbs. Int. I NR BR%I I t NT Br%I t I NB BR%I I NB BR%I I NB BR%I BR: Factor for Converting Intensity Per 100 Decays Through This Decay Branch, to Intensity Per 100 Decays of the Parent Nucleus NR: Factor for Converting Relative I to I Per 100 Decays Through This Decay Branch. NT: Factor for Converting Relative TI to TI Per 100 Decays Through This Decay Branch. NB: Factor for Converting Relative and Intensities to Intensities Per 100 Decays of This Decay Branch.
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Absolute intensities “Intensities per 100 disintegrations of the parent nucleus” Measured (Photons from -, + +, and decay) Simultaneous singles measurements Coincidence measurements
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Normalization Procedures 1.Absolute intensity of one gamma ray is known (%I ) Relative intensity I + I Absolute intensity %I + I Normalization factor N = %I / I Uncertainty N =[ ( I %I ) 2 +( I I x N Then %I l = N x I l I l = [( N/N) 2 + ( I I x I l I1I1 I2I2 %I
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 2.From Decay Scheme I Relative -ray intensity; : total conversion coefficient N x I x (1 + ) = 100% Normalization factor N = 100/ I x (1 + ) Absolute -ray intensity % I = N x I 00 (1 + ) Uncertainty % I = 100 x /(1 + ) 2 100 % II
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Total intensity from transition-intensity balance 200 150 100 95 0 -- TI( 7 ) = TI( 5 ) + TI( 3 ) If ( 7 ) is known, then I 7 = TI( 7 ) / [1 + ( 7 )] I6I6 I5I5 I4I4 I2I2 I3I3 I1I1 I7I7
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Equilibrium Decay Chain T 0 > T 1, T 2 are the radionuclide half-lives, For t = 0 only radionuclide A 0 exists, % I 3, I 3, and I 1 are known. Then, at equilibrium % I 1 = (% I 3 /I 3 ) × I 1 × (T 0 /(T 0 – T 1 ) × (T 0 /(T 0 – T 2 ) Normalization factor N = %I 1 / I 1 A0A0 A1A1 A2A2 A3A3 I1I1 I3I3 T0T0 T1T1 T2T2
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 Normalization factor N = 100 / I 1 (1 + 1 ) + I 3 (1 + 3 ) % I 1 = N x I 1 = 100 x I 1 / I 1 (1 + 1 ) + I 3 (1 + 3 ) % I 3 = N x I 3 = 100 x I 3 / I 1 (1 + 1 ) + I 3 (1 + 3 ) % I 2 = N x I 2 = 100 x I 2 / I 1 (1 + 1 ) + I 3 (1 + 3 ) Calculate uncertainties in %I 1, % I 2, and % I 3. Use 3% fractional uncertainty in 1 and 3. See Nucl. Instr. and Meth. A249, 461 (1986). To save time use computer program GABS - 100 % I3I3 I2I2 I1I1
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 4. Annihilation radiation intensity is known I ( +) = Relative annihilation radiation intensity X i = Intensity imbalance at the ith level = ( +ce) (out) – ( +ce) (in) r i = i / + i theoretical ratio to ith level X i = i + + i = + i (1 + r i ), therefore + i = X i / 1 + r i 2 [X 0 / (1 + r 0 ) + Σ X i / (1 + r i )] = I( +) ……… (1) [X 0 + Σ I i ( + ce) to gs ] N = 100 ………. (2) Solve equation (1) for X 0 (rel. gs feeding). Solve equation (2) for N (normalization factor). +ce) (in) ( +ce)(out) (++)2(++)2 (++)1(++)1 (++)0(++)0 ++++
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Jag Tuli DDP-Workshop Bucharest, Romania, May 08 5.X-ray intensity is known I K = Relative Kx-ray intensity X i = Intensity imbalance at the ith level = ( +ce) (out) – ( +ce) (in) r i = i / + i theoretical ratio to ith level X i = i + + i, so i = X i r i / 1 + r i (atomic vacancies); K = K- fluorsc.yield P Ki = Fraction of the electron-capture decay from the K shell I K = K [ 0 ×P K0 + Σ i × P Ki ] I K = K [P K0 × X 0 r 0 / (1 + r 0 ) + Σ P Ki × X i r i / 1 + r i ]…(1) [X 0 + Σ I i ( + ce) to gs] N = 100 …. (2) Solve equation (1) for X 0, equation (2) for N. +ce) (in) ( +ce)(out) (++)2(++)2 (++)1(++)1 (++)0(++)0 ++++
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