基于散射实验极化靶的2.5T/1.3K的动态核极化(DNP)系统的开发

Dynamic nuclear polarization system at 2.5T/1.3K for polarized target of scattering experiment

动态核极化法(Dynamic Nuclear Polarization,DNP)是利用热平衡下的电子在磁场中的高自旋极化率转移到原子核自旋的技术,从而极大的提高原子核自旋极化率.多种动态极化靶材料已广泛的用于自旋物理散射实验.本文介绍一种简单实用,共同开发的日本山形大学DNP系统,包括超导磁场,氦4蒸发恒冷器,微波系统以及NMR核磁共振检测系统,测得中子靶材料氘带丁醇(D-butanol)中氘核的极化率在2.5 T/1.3 K达到+6.5%.

Dynamic Nuclear Polarization(DNP)is an effective approach to transfer unpaired electrons high spin polarization to the nuclear and significantly improving the nuclear spin polarization.Various polarized target materials are used in scattering experiments of spin physics field.Here a simple and practical DNP system including superconducting magnet,cryostat,microwave system and Nuclear Magnetic Resonance(NMR)system jointly developed by Yamagata University of Japan is presented.The measured polarization of deuteron in the neutron target material D-butanol reaches+6.5%at 2.5 T/1.3 K.