Improved density measurement by FIR laser interferometer on EAST tokamak

• In 2012, the water-cooling Mo wall was installed in EAST.
• A schottky barrier diode detector is designed and used on EAST for the first time.
• The three-channel far-infrared laser interferometer can measure the electron density.
• The improved measurement and latest experiment results are reported.
• The signal we get in this experiment campaign is much better than we got in 2010.

A three-channel far-infrared (FIR) hydrogen cyanide (HCN) laser interferometer is in operation since 2010 to measure the line averaged electron density on experimental advanced superconducting tokamak (EAST). The HCN laser signal is improved by means of a new schottky barrier diode (SBD) detector. The improved measurement and latest experiment results of the three-channel FIR laser interferometer on EAST tokamak are reported.