论文标题
Proxima Centauri的蓝色光谱中的ALH线
AlH lines in the blue spectrum of Proxima Centauri
论文作者
论文摘要
ALH同位素的最近计算的Exomol线列表用于分析Proxima CEN（M5.5 V）的蓝色光谱（4000-4500Å）。观察到的光谱和计算光谱的比较可以鉴定A1π-x1σ+频段系统的大量27ALH线：覆盖1-0、0-0和1-1频段的光谱范围以明确解析的ALH线为主导。我们揭示了接近分离极限的过渡性质的扩散性质，而分离极限的形式越来越宽（最多5Å）和浅（最高到连续的混淆极限）ALH线曲线。 ALH扩散线的预测波长是系统地位移的。通过将辐射阻尼速率提高多达5个数量级，包括前交流态对线谱的影响扩大。我们通过比较观察到的和合成的恒星光谱来确定许多清洁0-0 Q分支过渡的阻尼率的经验值。我们发现在文献中可用的阻尼率和寿命之间有着极好的一致性。 27AL1H exomol和Realh光谱的比较表明，观察到的光谱由Exomol线列表更好地描述。在Proxima CEN频谱中搜索26AL1H线并未显示出任何显着特征。上限为27Al1h/26al1h {>} 100。
The recently-computed ExoMol line lists for isotopologues of AlH are used to analyse the blue spectrum (4000-4500 Å) of Proxima Cen (M5.5 V). Comparison of the observed and computed spectra enables the identification of a large number of 27AlH lines of the A1Π - X1Σ+ band system: the spectral range covering 1-0, 0-0 and 1-1 bands is dominated by clearly resolved AlH lines. We reveal the diffuse nature of transitions close to the dissociation limit which appears in the form of increasingly wider(up to 5 Å) and shallower (up to the continuum confusion limit) AlH line profiles. The predicted wavelengths of AlH diffuse lines are systematically displaced. The effect broadening by pre-dissociation states on the line profiles is included by increasing the radiative damping rate by up to 5 orders of magnitude. We determine empirical values of damping rates for a number of the clean 0-0 Q-branch transitions by comparing the observed and synthetic stellar spectra. We find excellent agreement between our damping rates and lifetimes available in the literature. A comparison of 27Al1H ExoMol and REALH spectra shows that the observed spectrum is better described by the ExoMol line list. A search for 26Al1H lines in the Proxima Cen spectrum does not reveal any notable features; giving an upper limit of 27Al1H/26Al1H {>} 100.
