AI 中文总结
研究系外行星 WASP-39b 上重水同位素 HDO，通过詹姆斯·韦布空间望远镜透射光谱反演其大气，得出水中氘与氢的比率，该值高于太阳系气态巨行星，其富集可能源于雪线外吸积物质或大气中的同位素过程。
AI 中文摘要
氢同位素常用于追踪宇宙中含氢物种的化学过程和起源，然而，系外行星上它们的丰度仍未确定。在此，我们报告了从热木星 WASP-39b 的詹姆斯·韦布空间望远镜透射光谱中反演得到的系外行星大气中重水分子 HDO 的大气反演证据，得出水中氘与氢的比率为$4.0^{+1.3}_{-1.1} \times 10^{-3}$。该推断值远高于太阳系气态巨行星的测量值，在数值上与一些原恒星和太阳系内部环境报告的值重叠。这种富集可能反映了雪线以外吸积的富含水的物质，或者是通过传输、光化学和随后的逃逸在可观测大气中的同位素过程。
英文摘要
Hydrogen-isotopologues are commonly used to trace the chemical processing and origin of hydrogen-bearing species throughout the Universe, however, their abundance remains unconstrained for extrasolar planets. Here, we report atmospheric retrieval evidence for the deuterated water molecule HDO in an exoplanet atmosphere, retrieved from James Webb Space Telescope transmission spectra of the hot Jupiter WASP-39 b, resulting in a deuterium-to-hydrogen ratio in water of $4.0^{+1.3}_{-1.1} \times 10^{-3}$. The inferred value is substantially higher than those measured for the Solar System gas giants and overlaps numerically with values reported for some protostellar and inner Solar System environments. This enrichment may reflect either inherited water-rich material accreted beyond the snow line or isotopic processing in the observable atmosphere through transport, photochemistry, and subsequent escape.
CommentsUnder review, comments welcome
