Evaluation of particle source rate and its influence on particle transport in fusion plasma

We have carried out numerical inversion of the Laplace transform for the observed line profile, and have derived the intensity distribution function against the atom temperature. The temperature dependence is interpreted to the spatial dependence, where other diagnostic results are used, so that the radial profile of photon emission rate is derived. The photon emission rate is then interpreted to the ionization rate with the help of collisional-radiative model calculation. From the ionization rate derived we have evaluated the particle confinement time τ_p as a function of the average minor radius, r_eff, for two discharges characterized by the different magnetic field strength. In the strong field case, a turning point is clearly seen in the τ_p profile at around r_eff = 0.6, which corresponds to the last closed magnetic flux surface. In the weak field case, the absolute confinement time is approximately one-order smaller than that in the strong field case.