Fabrication of Cr target for nuclear structure studies

Target fabrication is a vital part of any nuclear physics experiment because the results of the experiment depend heavily upon the quality of the target. Hence, fabrication of a proper target according to the requirement of the experiment is very desirable. Here we report on the fabrication of two sets of chromium target of different thicknesses required in spectroscopic and lifetime measurement for nuclear structure studies. Natural Cr is a hard, brittle metal which consists of ⁵²Cr isotope with relative abundance of 84%, ⁵³Cr with 9%, ⁵⁰Cr with 4% and ⁵⁴Cr with 2%. For lifetime studies, Doppler shifted attenuation method (DSAM) is a well known technique which requires a thin target on a high Z thick backing, so as to stop the recoil products inside the backing. The physical vapor deposition method is commonly used for fabrication of thin films of brittle material. Using this method, we have fabricated Cr target of thickness ∼0.6 mg-cm^-2 on a .∼9 mg-cm^-2 thick Au backing for DSAM and another of ∼1 mg-cm^-2 on a ∼10 mg-cm^-2 thick Au backing for spectroscopic studies at target preparation facility of Inter University Accelerator Centre (IUAC), New Delhi