Emittance measurements for the Illinois/CEBAF polarized electron source
Emittance measurements for the Illinois/CEBAF polarized electron source
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伊利诺斯州/CEBAF 极化电子源的发射率测量
DOI：
10.1109/pac.1995.505119
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
C. Sinclair
中科院分区：
文献类型：
--
作者：
B. Dunham;L. Cardman;C. Sinclair
从砷化镓发光的电子的横向热性质决定了本征光束发射度，这是偏振电子源和高亮度光源中一个重要的应用量。本文描述了利用Illinois/CEBAF极化电子源测量发射度的方法。在低电流下，发射度随激光光斑大小和激光波长的变化而变化。利用这些数据推断出波长在514 ~ 840 nm之间的砷化镓光电子的横向热能。在带隙附近，横向能量为/spl sim/34 meV，比典型热离子电子枪的光束能量低3倍。
The transverse thermal properties of the electrons photo-emitted from GaAs determine the intrinsic beam emittance, an important quantity in applications such as polarized electron sources and high-brightness sources. In this paper, emittance measurements using the Illinois/CEBAF polarized electron source are described. The emittance was measured as a function of both the laser beam spot size and laser wavelength at low currents. The data was used to infer the transverse thermal energy of the electrons photoemitted from GaAs for wavelengths between 514 and 840 nm. Near the bandgap the transverse energy is /spl sim/34 meV, a factor of 3 lower than that of the beam from a typical thermionic electron gun.