Early optical spectra of nova V1369 Cen show presence of Lithium
L. Izzo, M. Della Valle, E. Mason, F. Matteucci, D. Romano, L. Pasquini, L. Vanzi, A. Jordan, J. M. Fernandez, P. Bluhm, R. Brahm, N. Espinoza, R. Williams
备注：
6 pages, 5 figures, accepted for publication in ApJLetters
我们提出了早期的高分辨率光谱观测的新星V1369岑。我们在6695.6欧姆处探测到一个吸收特征，我们将其确定为蓝移的$^7$ Li I $λ$ 6708欧姆。在不同时期获得的新星的五个高分辨率光谱中观察到了以-550公里/秒移动的吸收线。根据这条吸收线的强度，我们推断，一个单一的新星爆发可以注入银河系$M_{Li} =$ 0.3 - 4.8 $\times 10^{-10}$ M $_{\odot}$。鉴于目前对银河系新星率的估计，这个数量足以解释在年轻恒星群中观察到的锂过剩的令人费解的起源。
英文摘要：
We present early high resolution spectroscopic observations of the nova V1369 Cen. We have detected an absorption feature at 6695.6 Å\, that we have identified as blue--shifted $^7$Li I $λ$6708 Å. The absorption line, moving at -550 km/s, was observed in five high-resolution spectra of the nova obtained at different epochs. On the basis of the intensity of this absorption line we infer that a single nova outburst can inject in the Galaxy $M_{Li} =$ 0.3 - 4.8 $\times 10^{-10}$ M$_{\odot}$. Given the current estimates of Galactic nova rate, this amount is sufficient to explain the puzzling origin of the overabundance of Lithium observed in young star populations.
Of all the light elements, the evolution of lithium (Li) in the Milky Way is perhaps the most difficult to explain. Li is difficult to synthesize and is easily destroyed, making most stellar sites unsuitable for producing Li in sufficient quantities to account for the proto-solar abundance. For decades, novae have been proposed as a potential explanation to this 'Galactic Li problem', and the recent detection of 7Be in the ejecta of multiple nova eruptions has breathed new life into this theory. In this work, we assess the viability of novae as dominant producers of Li in the Milky Way. We pre…
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