Measurement of molybdenum ion density for L-mode and H-mode plasma discharges in the EAST tokamak**Project supported by the National Key Research and Development Program of China (Grant No. 2017YFE031300), the Key Program of Research and Development of Hefei Science Center of China (Grant No. 2017HSC-KPRD002), the National Natural Science Foundation of China (Grant No. 11805231), the Natural Science Foundation of

Abstract

We report the measurement of total molybdenum ion density for L-mode and H-mode plasmas on EAST using spectral lines observation and calculation based on an impurity transport code. A flat-filed extreme ultraviolet spectrometer with some spatial resolution is used to obtain the radial profiles of molybdenum spectral line emissions. The absolute calibration for the extreme ultraviolet spectrometer is finished by comparing the calculated bremsstrahlung intensity with the readings of CCD detector. Molybdenum ion transport study is performed using the radial ion density profiles and one-dimensional impurity transport code STRAHL. The total molybdenum density profiles are determined from the transport analysis. The molybdenum density during L-mode and H-mode phases are obtained, which are about 3 and 4 orders of magnitude smaller than the electron density, respectively. An inward pinch is found during the H-mode phase that leads to the peaked profile of molybdenum density.