Spin polarizations of positron beams generated using electrostatic and magnetic transportation systems with 68Ge and 22Na sources
Spin polarizations of positron beams generated using electrostatic and magnetic transportation systems with 68Ge and 22Na sources
复制标题
使用 68Ge 和 22Na 源的静电和磁性传输系统产生的正电子束的自旋极化
DOI：
10.1088/1742-6596/505/1/012033
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
H. Li and A. Kawasuso
中科院分区：
文献类型：
--
作者：
M. Maekawa;Y. Fukaya;H. Zhang;H. Li and A. Kawasuso
使用68 Ge和22 Na源与钨减速器产生的静电正电子束的自旋极化分别为47%和30%。一个可比的自旋极化（27%），得到了大大减少的光束直径（0.5毫米），当使用电磁透镜，22钠源和钨减速器。在该系统中，用固体氖慢化剂代替钨慢化剂，在保持自旋极化的情况下，束流通量得到了显著的提高。用上述光束测量的多晶铁湮没辐射谱的多普勒展宽显示出明显的场反转不对称性。
Spin polarizations of electrostatic positron beams generated using 68 Ge and 22 Na sources with tungsten moderators were 47% and 30%, respectively. A comparable spin polarization (27%) was obtained with much reduced beam diameter (0.5 mm), when electromagnetic lenses, a 22 Na source and a tungsten moderator were used. Replacing the tungsten moderator with a solid neon moderator in this system, the beam flux was significantly enhanced with maintaining the spin polarization. The Doppler broadening of annihilation radiation spectra of polycrystalline Fe measured using the above beams showed clear asymmetry upon field reversal.