Thickness and uniformity measurements of nuclear targets

The methods of target thickness and uniformity measurements are introduced, which include weighing, α-particle thickness gauge, quartz thickness gauge, optical transmittance and Rutherford backscattering. An α-particle gauging which measures target thicknesses up to several μm is metioned. The fast thickness measurements for C, Au and Cu targets by spectrophotometer are given. A high sensitive quartz gauge which can measure minimum deposit of 0.04 μg/cm2 is described. Thickness and impurity determinations by RBS with accuracy better than 5% are summarized