The O2 atmospheric 0‐0 band and related emissions at night from Spacelab 1
The O2 atmospheric 0‐0 band and related emissions at night from Spacelab 1
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太空实验室 1 夜间的 O2 大气 0-0 波段和相关排放
DOI：
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发表时间：
1985
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通讯作者：
R. Laher
中科院分区：
文献类型：
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作者：
M. Torr;D. Torr;R. Laher
O2的c¹Σ， c³Δ（现更名为A³Δu）和A³Σ激发态的光化学与低层热层和上层中间层的能量学以及该区域的原子氧浓度有关。通过遥感获得原子氧浓度分布的一种方法是通过5577 A的O（¹S）发射，前提是对O（¹S）的产生和损失机制有很好的了解。O（¹S）现在被认为是由上述三种O2状态（巴斯机制）之一的两步过程产生的。早些时候，它被认为是在原子氧的三体重组中直接产生的（查普曼机制）。虽然近年来的经验证据倾向于第一种选择，但中间状态的身份仍然存在问题。O2大气带产生于b¹Σ状态，它通过类似于Barth机制的两步过程填充，同样涉及中间状态。在本文中，我们利用在Spacelab 1航天飞机任务中使用的一系列成像光谱仪收集的夜间中层大气光谱测量数据来研究这些相关问题。此时，这个问题仍然包含太多的不确定参数，无法通过数据明确地解决。然而，数据似乎得到了来自O2（c¹Σ）的O2（b¹Σ）的最好支持，尽管指出了额外的O2来源（b¹Σ）。O（¹S）更接近地表示为具有[O]³依赖性的查普曼特征的过程，如果使用先前接受的速率系数，在这种情况下，这似乎有利于O2（a '³Δ）作为中间态。（我们的数据集中没有足够的信息来拒绝（A³）状态作为O（¹S）前体，尽管这在其他研究中已经被拒绝了。）然而，对于潜在中间态及其振动激发形式的速率系数和主要猝灭种类的认识尚不稳定。如果关于O2（b¹Σ）态的最新实验室信息在中间态的O和O2的相对淬火作用方面是正确的，但在中间态的产生速率方面是不正确的，则可能存在另一种解决方案。在这种情况下，O2大气带和O（¹S）可以从相同的中间态产生，但O（¹S）只能从产率为0.01的振动激发态产生，而O2大气带也可以从产率至少为0.80的低振动态产生。
The photochemistry of the c¹Σ, C³Δ (now renamed the A′³Δu), and A³Σ excited states of O2 is of relevance to the energetics of the lower thermosphere and upper mesosphere and to the atomic oxygen concentration in this region. A means of obtaining the atomic oxygen concentration profile by remote sensing is via the O(¹S) emission at 5577 A provided the production and loss mechanisms of the O(¹S) are well understood. The O(¹S) is now believed to be produced in a two-step process originating with one of the above three states of O2 (the Barth mechanism). Earlier, it was thought to be produced directly in three-body recombination of atomic oxygen (the Chapman mechanism). While the empirical evidence in recent years has tipped toward the first of these alternatives, the identity of the intermediate state is still in question. The O2 atmospheric bands arise from the b¹Σ state, which is populated via a two-step process similar to the Barth mechanism, again involving an intermediate state. In this paper we investigate these related issues using spectral measurements gathered on the nocturnal middle atmosphere with an array of imaging spectrometers flown on the Spacelab 1 shuttle mission. At this time the problem still contains too many uncertain parameters to be unambiguously resolved by the data. However, the data appear best supported by the O2(b¹Σ) arising from the O2(c¹Σ), although an additional source of O2(b¹Σ) is indicated. The O(¹S) is more closely represented by a process with the Chapmanlike characteristics of an [O]³ dependence, which seems to favor the O2(A′³Δ) as the intermediate state in this case if the previously accepted rate coefficients are used. (We do not have sufficient information in our data set to reject the (A³) state as the O(¹S) precursor, although this has been rejected in other studies.) However, the state of knowledge of the rate coefficients and dominant quenching species for the potential intermediate states and their vibrationally excited forms is not yet stable. If the latest laboratory information on the O2(b¹Σ) state is correct in the relative roles of quenching by O and O2 of the intermediate state but incorrect in the rate of production of the intermediate state, another solution is possible. In this case the O2 atmospheric bands and O(¹S) can arise from the same intermediate state but with O(¹S) being generated only from vibrationally excited states with a yield of 0.01 and the O2 atmospheric generated also from the low vibrational states with a yield of at least .80.