论文标题
通过组合高分辨率和低分辨率数据,检索HR 8799 C的C和O丰度
Retrieving C and O Abundance of HR 8799 c by Combining High- and Low-Resolution Data
论文作者
论文摘要
直接成像的多人系统HR 8799的形成和演化途径仍然很神秘。对行星气氛的化学成分的准确限制是解决谜团的关键。我们在HR 8799〜C上进行了详细的大气检索,以使用光度数据以及低分辨率和高分辨率的光谱数据(r $ \ sim $ 20-35,000)来推断化学丰度和丰度比率。我们特别检索[C/H],[O/H]和C/O,发现它们为0.55 $^{+0.36} _ { - 0.39} $,0.47 $^{+0.31} _ { - 0.32} $,和0.67 $^$^{+0.12 $^{+0.12} _ {+0.12} _ {-0.15} $超级恒星C和O的丰度,但出色的C/O比揭示了HR 8799〜C的潜在形成途径。行星C,以及系统中的其他天然气巨型行星,早期形成(可能在$ \ sim $ 1 Myr),然后通过CO ICELINE以外的固体积聚,在C和O中进一步大气丰富。在向内迁移到行星当前位置的早期阶段之前或进行了富集。
The formation and evolution pathway for the directly-imaged multi-planetary system HR 8799 remains mysterious. Accurate constraints on the chemical composition of the planetary atmosphere(s) are key to solving the mystery. We perform a detailed atmospheric retrieval on HR 8799~c to infer the chemical abundances and abundance ratios using a combination of photometric data along with low- and high-resolution spectroscopic data (R$\sim$20-35,000). We specifically retrieve [C/H], [O/H], and C/O and find them to be 0.55$^{+0.36}_{-0.39}$, 0.47$^{+0.31}_{-0.32}$, and 0.67$^{+0.12}_{-0.15}$ at 68\% confidence. The super-stellar C and O abundances, yet a stellar C/O ratio, reveal a potential formation pathway for HR 8799~c. Planet c, and likely the other gas giant planets in the system, formed early on (likely within $\sim$1 Myr), followed by further atmospheric enrichment in C and O through the accretion of solids beyond the CO iceline. The enrichment either preceded or took place during the early phase of the inward migration to the planet current locations.