Transverse electron cooling of heavy molecular ions has been studied at the Test Storage Ring (TSR). Electron beams from a cold GaAs:(Cs,O) photocathode, with kinetic energies down to 31 eV, have been used for cooling of singly-charged ions of masses up to 41 u. We believe that these are the heaviest singly-charged ions for which successful electron cooling has been reported so far. Transverse ion-beam emittances $\ll 1\mu \mathrm{m}$ were reached after typically several seconds of cooling time. The measured transverse cooling rates agree with a simple binary-collision model, assuming a transverse electron temperature of approximately $1\mathrm{meV}/k_{\mathrm{B}}$. The results serve as benchmark for electron cooling at the new Cryogenic Storage Ring, which uses the same photocathode electron source and is targeting singly-charged ions of even higher mass.

中文翻译：

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重分子离子的横向电子冷却

在测试存储环（TSR）上已经研究了重分子离子的横向电子冷却。来自动能低至31 eV的GaAs：（Cs，O）冷光电阴极的电子束已用于冷却质量高达41 u的单电荷离子。我们认为，这些是迄今为止报道的成功的电子冷却方法中最重的单电荷离子。横向离子束发射率$\ll \mathrm{1个}\mu \mathrm{米}$通常在几秒钟的冷却时间后才能达到。假设横向电子温度约为，则测得的横向冷却速率与简单的二元碰撞模型相符。$\mathrm{1个}\mathrm{病毒}/{ķ}_{\mathrm{乙}}$。该结果可作为新低温存储环中电子冷却的基准，该低温存储环使用相同的光电阴极电子源，并以更高质量的单电荷离子为目标。