标题： 恒星活动与近距系外行星质量之间的相关性？ 显示英文标题

标题： A correlation between host star activity and planet mass for close-in extrasolar planets?

摘要： 恒星的活动水平受多种恒星特性的影响，例如恒星自转、光谱类型和恒星伴星的存在。 与双星类似，行星伴星也被认为能够导致其宿主恒星的活动水平升高，尽管程度较低。 尤其是在X射线中，这种影响很难检测，因为冷恒星的日冕表现出相当大的内在变化。 最近，基于ROSAT全天空调查的档案X射线数据，检测到了近距离系外行星的质量与其宿主恒星X射线光度之间的相关性。 这一发现被解释为恒星-行星相互作用的证据。 我们在分析中表明，这种相关性是由于所使用的X射线数据的流量限制以及径向速度方法的内在行星可探测性导致的选择效应，并因此不追踪可能的行星诱导效应。 我们还表明，在结合XMM-Newton和ROSAT数据得出的相应完整样本中，这种相关性并不存在。 显示英文摘要

摘要： The activity levels of stars are influenced by several stellar properties, such as stellar rotation, spectral type and the presence of stellar companions. In analogy to binaries, planetary companions are also thought to be able to cause higher activity levels in their host stars, although at lower levels. Especially in X-rays, such influences are hard to detect because coronae of cool stars exhibit a considerable amount of intrinsic variability. Recently, a correlation between the mass of close-in exoplanets and their host star's X-ray luminosity has been detected, based on archival X-ray data from the ROSAT All-Sky Survey. This finding has been interpreted as evidence for Star-Planet Interactions. We show in our analysis that this correlation is caused by selection effects due to the flux limit of the X-ray data used and due to the intrinsic planet detectability of the radial velocity method, and thus does not trace possible planet-induced effects. We also show that the correlation is not present in a corresponding complete sample derived from combined XMM-Newton and ROSAT data.