Aeronomy of Extra-Solar Giant Planets
Aeronomy of Extra-Solar Giant Planets
复制标题
太阳系外巨行星的天文学
DOI：
--
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
W. Ip
中科院分区：
文献类型：
--
作者：
R. Yelle;H. Lammer;W. Ip
照射在太阳系外巨行星上的强烈恒星紫外线辐射场使其高层大气发生深刻变化。高层大气温度可达数万开尔文，导致H₂热分解为H。恒星的电离通量将H转化为H⁺。高温还导致H有较大的逃逸率，但除了轨道最小的行星外，这种通量都不足以影响行星的演化。逃逸率大到足以带走较重的原子，如C和O。对于轨道非常小的行星，当希尔球位于大气层内部时，逃逸不受限制，并可影响行星的演化。
The intense stellar UV radiation field incident upon extra-solar giant planets causes profound changes to their upper atmospheres. Upper atmospheric temperatures can be tens of thousands of kelvins, causing thermal dissociation of H2 to H. The stellar ionizing flux converts H to H+. The high temperatures also drive large escape rates of H, but for all but the planets with the smallest orbits, this flux is not large enough to affect planet evolution. The escape rate is large enough to drag off heavier atoms such as C and O. For very small orbits, when the hill sphere is inside the atmosphere, escape is unfettered and can affect planet evolution.