Measuring the 208Tl range of E ≤ 116 keV in silver films

Abstract In this study, measurements of the effective range of 208 Tl ions ( E ≤ 116 keV) emanating from the recoil daughters from 220 Rn were carried out. The target used was a set of thin silver films. The amount of the stopped 208 Tl ions in each film was determined by measuring the short-lived (~3 m) $$\beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>β</mml:mi> </mml:math> activity of 208 Tl, where the effective range was found to be 11.8 ± 2.36 µg/cm 2 . This value is in agreement (~20%) with Monte Carlo simulations using SRIM-TRIM software. These simulations also included the attenuation of 208 Tl ions caused by the interaction of the ions with the Al sheet holding the 208 Tl ion source. After adding the weakened 208 Tl source to the simulation, the resulting width of the simulated spectrum was in agreement with experiment (to within 4.5%). Graphical abstract