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coulomb excitation data analysis codes; gosia 2007 - Physics and ...

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line 152 Eu 182 Tanumber (keV) (keV)1 121.783 31.7372 244.692 65.7223 295.939 67.7504 344.276 84.6805 367.789 100.1066 411.115 113.6737 443.967 116.4218 488.661 152.4309 564.021 156.39010 586.294 179.39711 688.678 198.35012 778.903 222.10813 867.388 229.32214 964.131 264.07815 1005.279 927.98316 1085.914 1001.69617 1112.116 1113.41418 1212.950 1121.29919 1299.124 1157.50520 1408.011 1189.05121 1528.115 1221.40622 1231.01923 1257.42124 1273.73525 1289.158Any unobserved line that is to be excluded from the fit mustbeenteredasA = ∆A =0, at the keyboard aswell as in a file.Data for other sources than 152 Eu <strong>and</strong> 182 Ta easily can be added to the code in the future, should theneed arise. Similarly it is trivial to include additional 152 Eu <strong>and</strong> 182 Ta lines in the lists.1.2 Experimental <strong>and</strong> theoretical efficiencyFor each calibration line GREMLIN calculates the relative efficiency <strong>and</strong> root-mean-square error:s µ∆Aε = A 2 µ 2 ∆I∆ε = ε +IA I<strong>and</strong> makes a transformation to the variables which are then internally used for the fit, i.e.x ≡ log E E 0y ≡ log ε ∆y = ∆εεThe logarithms are of base e <strong>and</strong> E 0 =50keV.The functional form used by GREMLIN is factored into four functions that separately account for γ-rayabsorption, higher energy, lower energy detection efficiencies, <strong>and</strong> electronic thresholds in order to obtainwell-behaved functions that do not exhibit pathological behaviour such as at K-edges etc. That is, thefunctional form of the detection efficiency used isε(E) =A(E)P (E; a 1 ...a n )F (E; f)W (E; b, c)with the parameters a 1 ...a n , f, b, <strong>and</strong>c to be determined. The separate terms are discussed below.1.3 Attenuation factor191

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