Power transmission factor through the sheath in deuterium plasmas for virgin as well as nanostructured tungsten

Power transmission factor (PTF) through the sheath of deuterium plasmas with hot electron component on virgin as well as nanostructured tungsten due to helium pre-irradiations are studied experimentally and compared with a PTF theory. PTF for nanostructured tungsten is larger than that for normal one, the reasons of which are discussed in terms of surface characteristics.