Characteristics of momentum transport in JT-60U H-mode plasmas

Properties of the toroidal momentum diffusivity (chi(phi)) and the convection velocity (V-conv) in JT-60U H-mode plasmas have been obtained by plasma parameter scans such as the plasma current, neutral beam heating power and electron density. The toroidal momentum diffusivity increases with increasing heat diffusivity (chi(i)) over a wide range of radii (r/a = 0.2-0.6) and chi(phi)/chi(i) similar to 0.7-3 at the half radius (r/a = 0.5). The inward convection velocity (-V-conv) increases with increasing chi(phi), and -V-conv/chi(phi) similar to 0.5-2 (m(-1)) at r/a = 0.5. It is found that the ratio chi(phi)/chi(i) increases with increasing ion temperature and decreases with increasing electron density. These tendencies are observed in other radial positions of r/a = 0.3, 0.4 and 0.6. Moreover, the ratio -V-conv/chi(phi) at r/a = 0.4, 0.5 and 0.6 increases with increasing ion and electron temperatures or temperature gradients.