Alpha spectrometry 2015 A Paradigm Shift in nuclear

Alpha spectrometry 2015 A Paradigm Shift in nuclear spectrum analysis Paper By Dr. W. Westmeier, K. Siemon, IEEE Transactions on Nuclear Science, Vol. 59/4 (2012) 1296 New programming strategies : Physics, no Numerology for: - peakshapes - shape of baseline - shape of background - resolution function (no SQRT) - true coincidence losses - …. . other Fuzzy logic for: - regioning - height of BGND before and after region - peaksearch - peakfit - repeated fit - various methods (Gauss, AWMI, Sieder, . . ) - nuclide assignment - …. . other

Alpha spectrometry 2015 α-particle spectrometry • • ALPS software can quantify even very complex and overlapping peaks yields quantitative isotope activities tracer analysis is integrated in the software a very complete library (390 nuclides with 1270 lines) is available

Alpha spectrometry 2015 After our Paradigm Shift extreme analyses became possible Quantitative separation of peaks from 239 Pu and 240 Pu

Alpha spectrometry 2015 Quantitative separation of peaks from 239 Pu and 240 Pu

Alpha spectrometry 2015 Fit of very complex and overlapping peak multiplett Example: old 231 Pa source with all its progeny

Alpha spectrometry 2015 Fit of dried drop sample from river water Example: 1 l river water preconcentrated to 1 ml, 200 µl drops dried on sample plate. 238 U and (234 U+230 Th+226 Ra) are found. 238 U contents in river is 0. 8 Bq/l

Alpha spectrometry 2015 Fit of powdered granite sample, grain size ≥ 80 µm Example: approx. 1 gram of granite powder was measured in a gridded ionisation chamber for over five days. 238 U and 232 Th progeny is completely quantified

Alpha spectrometry 2015 Fit of filter paper sample from city air at main road Example: 1“ dia. filter paper was loaded for 1 day and measured directly after 42 h waiting time. 212 Bi and 212 Po are quantified yielding the 220 Rn (thoron) concentration in the air. Note β-α coincidences above channel 450

Alpha spectrometry 2015 Fit of ALGADE air sampler filter paper (1 month sampling) Example: filter paper was loaded for 1 month and measured directly with PIPS. 238 U and all progeny are quantified - no chemistry, no sample preparation

Alpha spectrometry 2015 Modern α-spectrometry can do it all with ALPS • High-precision analysis of spectra from thin samples • Quantitative data through use of tracer nuclides • Separation of peaks that were impossible before • Analysis of spectra from thick samples • Quantification through calculated efficiency • Very simple sample preparation - drying of drop samples - ashing of organic material - grinding of solids