标题： 恒星在三星系统中的摆动能否模拟行星？ 显示英文标题

标题： Can stellar wobble in triple systems mimic a planet?

摘要： 已经通过测量母星的摆动发现了第一批太阳系外行星。 这种摆动导致了三个可观测量的周期性调制：径向速度、天球上的位置和周期信号的到达时间。 我们表明，同样的摆动（因此这三个可观测量的调制）可能是由于更遥远的双星伴星的存在。 因此，单独观察摆动并不能构成行星探测的证明。 特别是，通过对摆动进行天文学测量确认并不一定能够充分证明通过径向速度检测到的行星候选者的存在。 我们在这里讨论必须满足的附加条件。 我们研究了已经检测到的行星候选者的摆动，并发现对于每个案例，都可以排除由双星伴星引起的摆动。 但对于宽轨道上类似土星的行星，在未来的探测中可能存在歧义，特别是在空间天文学任务中。 我们得出结论，在某些情况下，需要进一步的观测（例如直接成像）来确定行星的存在。 显示英文摘要

摘要： The first extrasolar planets have been detected by the measurement of the wobble of the parent star. This wobble leads to the periodic modulation of three observables: the radial velocity, the position on the sky and the time of arrival of periodic signals. We show that the same wobble, and therefore the same modulation of the three observables, can be due to the presence of a more distant binary stellar companion. Thus, the observation of the wobble does not, by itself, constitute a proof of a planet detection. In particular, astrometric confirmation of a wobble does not necessarily provide a sufficient proof of the existence of a planet candidate detected by radial velocity. Additional conditions, which we discuss here, must be fulfilled. We investigate the observed wobble for the planet candidates already detected and we find that, for each case, a wobble due to a binary stellar companion can be excluded. But for apparent Saturn-like planets in wide orbits, there may be an ambiguity in future detections, especially in spaceborne astrometric missions. We conclude that, in some cases, a definitive proof for the presence of a planet requires further observations such as direct imaging.