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Abstract Solid targets for nuclear measurements that use α -particle beams commonly experience a form of degradation known as blistering. The effect can prevent the use of solid targets for high intensity α -particle experiments, often necessitating complex gas target systems. To combat this problem, three different blister resistant target backings were designed for use in direct reaction measurements with high intensity α -particle beams. The blister resistant target designs utilize gas diffusive properties of fused silica, sintered metal, and porous evaporated metal. Each target was implanted with 22Ne ions and bombarded with α -particle beam to test blister resistance. Targets were characterized and monitored using the 22Ne(p , γ)23Na reaction to determine the degradation of implanted material, and compare them to typical implanted noble gas targets. We find that all targets studied exhibit resistance to blistering, with the porous evaporated metal targets displaying the least amount of target material degradation. [ABSTRACT FROM AUTHOR]

Isotopically pure molybdenum targets are essential in various nuclear science measurements. For studies of cross sections of capture reactions on molybdenum, uniform targets with areal densities of hundreds of μ g/cm 2 are desired. Mechanical rolling of enriched metal pieces or vacuum sputtering methods used in previous studies to prepare molybdenum targets are challenging and involve labor- and time-intensive processes. Therefore, reliable and straightforward methods to produce molybdenum targets are crucial. We have developed a new double-step method to produce targets meeting these needs. The first step consists of evaporating isotopically enriched MoO 3 onto gold backings. The second step involves the reduction of the oxide layer in a 5% H 2 -Ar environment to obtain molybdenum targets. X-ray fluorescence (XRF) spectroscopy, X-ray Diffraction (XRD), a scanning electron microscope/focused ion beam milling, and energy-dispersive X-ray spectroscopy (EDS) were used to characterize the targets. These methods show that the targets exhibit a uniform coverage of Mo over the gold backings. However, significant volume shrinkage occurring during the reduction of MoO 3 creates a porous Mo layer where the gold diffuses due to the high processing temperatures, resulting in mixed Mo–Au layers. • Isotopically pure Mo targets were prepared on gold backings. • Target preparation include vacuum evaporation and hydrogen reduction steps. • The characteristics of targets were investigated by XRD, XRF, SEM/FIB/EDS methods. [ABSTRACT FROM AUTHOR]