Sandwich targets of 0.5 mg/cm(2) C with 4 mg/cm(2) ferromagnetic Gd on 3 mg/cm(2) Ta support with 3.5 mg/cm(2) Cu backing

摘要

For high precision measurements of magnetic moments and reduced transition probabilities by the combined technique of projectile Coulomb excitation in inverse kinematics and transient magnetic fields sandwich targets of carbon and gadolinium had to be developed. A Gd layer of 4 mg/cm(2) was evaporated onto 1-3 mg/cm(2) Ta backings heated to 800 K for optimum ferromagnetic properties of the Gd, A Cu film of 3.5 mg/cm(2) was then deposited on the reverse side of the Ta backing. The Cu was required for stopping the Coulomb excited beam ions in a hyperfine interaction-free medium and for cooling the Gd film below its Curie temperature. The sandwich was then completed with 0.5 mg/cm(2) C-nat deposited onto the Gd. The adherence of evaporated carbon on the ferromagnetic gadolinium was found to be poor, and good results were not easily reproduced. Therefore, deposition of carbon by laser plasma ablation was also investigated. (C) 2001 Elsevier Science B.V. All rights reserved. References: 11