Improved H mode with flat central q profile on EAST*

High betaN (\textasciitilde 1.8) plasma with good confinement (H98y2\textasciitilde 1.1) on EAST tokamak has been reported recently. These ELMy H-mode plasmas with B$_{\mathrm{t}}=$1.6T, I$_{\mathrm{p}}=$400 kA and q$_{\mathrm{95}}\approx $4.5 were heated by lower hybrid wave and neutral beam injection. The internal transport barrier (ITB) and edge transport barrier (ETB) are both observed with m/n$=$1/1 fishbone, which were identified to clamp central~q~at values close to unity. Implying an improved H-mode with flat central q profile and absence of sawteeth, like other devices. Accurate q profile, key profile for developing scenarios aim at high performance H mode, were derived by Polarimeter-interferometer (POINT) measurement as constraint. Base on the optimized current profile, better confinement (H98y2\textasciitilde 1.4) with an electron ITB was obtained also with flat central q profile and absence of sawteeth at high betaP (\textasciitilde 2) regime with B$_{\mathrm{t}}=$2.5T, I$_{\mathrm{p}}=$400 kA. Both high betaN$_{\mathrm{\thinspace \thinspace }}$regime and high betaP$_{\mathrm{\thinspace }}$regime H mode, are characterized by a stationary flat central q profile q0$\ge $1, but typically close to 1, absence of sawteeth, H98(y,2) \textgreater 1 and simultaneously, with ITB.