394.6 GHz CW gyrotron FU CW II for DNP/NMR at 600 MHz

Summary form only given. Recently, medium power, sub-THz gyrotrons were developed for application to DNP-NMR experiment for enhancing the sensitivity of NMR. In FIR FU, 394.6 GHz CW gyrotron FU CW II which is the second gyrotron of Gyrotron FU CW Series has been developed for DNP/NMR at 600 MHz under a collaboration with Institute of Protein Research, Osaka University. The output power and the frequency are 32 W at the CW operation and 394.3 GHz at the second harmonic operation. The width of frequency spectrum is as narrow as 10 kHz. We have already installed the gyrotron on 600 proton NMR device at Osaka University and hope to begin the DNP experiment soon. We will present the operation performance of gyrotron FU CW II.