论文标题
自适应光学的原子过渡
Atomic transitions for adaptive optics
论文作者
论文摘要
本文回顾了高层大气中的原子和离子，包括Mesospheric Metals Na，Fe，Mg $^+$，Si $^+$，Ca $^+$，K以及非金属物种N，N $^+$，O，H，考虑其对天文适应性光学的潜力。 Na和Fe是创建多色激光导恒星的最佳候选者，最高的回报来自于两个波长的激发来实现的过渡。 Ca $^+$和Si $^+$具有强大的可见光过渡，但需要短的波长，超出大气截止，才能从地面进行激发。原子O，N $^+$在中层中具有强大的过渡和高丰度。这些物种的色谱柱密度和横截面的乘积可以高达O $ 10^5 $，而N $^+$的乘积可能高达$ 10^5 $，这使它们成为了放大自发排放的潜在候选者。但是，它们需要真空 - 硫化物波长才能激发。
This paper reviews atoms and ions in the upper atmosphere, including the mesospheric metals Na, Fe, Mg$^+$, Si$^+$, Ca$^+$, K and also non-metallic species N, N$^+$, O, H, considering their potential for astronomical adaptive optics. Na and Fe are the best candidates for the creation of polychromatic laser guide stars, with the strongest returns coming from transitions that can be reached by excitation at two wavelengths. Ca$^+$ and Si$^+$ have strong visible-light transitions, but require short wavelengths, beyond the atmospheric cutoff, for excitation from the ground state. Atomic O, N and N$^+$ have strong transitions and high abundances in the mesosphere. The product of column density and cross section for these species can be as high as $10^5$ for O and several hundred for N and N$^+$, making them potential candidates for amplified spontaneous emission. However they require vacuum-ultraviolet wavelengths for excitation.
