Preparation of thin target foil of high density materials via rolling method

Nuclear physics experiments need thin (1-10 mg/cm²) self-supporting target foils. If the material of the target is malleable, then most of the times such foils can be made via rolling method. The rolling method of making target is cost effective and yields much stronger foils compared to the foils prepared than obtained with any other available methods. The targets made by rolling method, due to their crystalline structure are stronger in nature and therefore have better prospects of withstanding in a high energy heavy-ion reaction experiments than the targets prepared by vacuum evaporation. For high density materials like Gold, Tungsten, lead, etc. the conventional rolling method fails to yield good quality thin foils of thicknesses less than ~ 2 mg/cm². Preparing foils of thickness less than 2 mg/cm² of these materials, some extraordinary efforts with improved technique are needed. In the past, numerous attempts have been made to prepare such thin foils via rolling method making use of various techniques. In the present work, we report the making of thin self-supporting gold foils of thickness in the range of ~ 1.0 mg/cm². For making this foil, we have adopted some novel methods, which will be discussed at the time of presentation. (author)