抄録
Characteristic X-rays are emitted from ECR plasmas of various rare gases. In the case of krypton gas, its spectrum is regarded as to be monochromatic. It is found that the intensity depends on gas pressure under a constant microwave power and an optimum pressure exists for the maximum characteristic X-ray intensity. The discussion for the X-ray contrast and the patient exposure suggests the necessity of the monochromatic X-rays whose energy can be changed depending on the objects. The ECR plasmas which can produce characteristic X-rays of various elements may be promising as such X-ray generator.
