论文标题
明亮的，连续的冷自由基束
Bright, continuous beams of cold free radicals
论文作者
论文摘要
我们展示了一种低温缓冲气体冷却的分子束源，能够通过激光消融在长达60秒的时间内通过激光消融产生明亮的，连续的冷束和缓慢的自由基。源设计使用封闭的液态氦液储层作为大型热质量，以最大程度地减少加热并确保在操作过程中可再现的束性能。在典型条件下，来源产生我们的测试物种SRF的光束，其中包含$ 5 \ times10^{12}〜$分子每秒$ x^{2}σ（v = 0，n = 1）$状态，旋转温度为$ 1.0（2）〜$ k，并为$ 1.0 $ k和forport veLocity and forther Velocity and forther velocity and forther veLocity and the forther veLocity $ 1400 $ m/s。对于多个电池几何，梁的性能是稳健且没有变化的，但非常依赖于氦气缓冲液流量，这必须是$ \ geq10〜 $每分钟标准立方厘米，以产生明亮的，连续的分子束，以换成$ 55〜 $ hz的消融重复速率。
We demonstrate a cryogenic buffer gas-cooled molecular beam source capable of producing bright, continuous beams of cold and slow free radicals via laser ablation over durations of up to 60~seconds. The source design uses a closed liquid helium reservoir as a large thermal mass to minimize heating and ensure reproducible beam properties during operation. Under typical conditions, the source produces beams of our test species SrF, containing $5\times10^{12}~$molecules per steradian per second in the $X^{2}Σ(v=0, N=1)$ state with a rotational temperature of $1.0(2)~$K and a forward velocity of $140~$m/s. The beam properties are robust and unchanged for multiple cell geometries but depend critically on the helium buffer gas flow rate, which must be $\geq10~$ standard cubic centimeters per minute to produce bright, continuous beams of molecules for an ablation repetition rate of $55~$Hz.
