论文标题
大多数行星可能有超过5个MYR的形成时间
Most planets might have more than 5 Myr of time to form
论文作者
论文摘要
原星盘的寿命是行星形成研究的关键参数。恒星簇中磁盘分数的观察意味着中位磁盘寿命为1-3 Myr。这个非常短的磁盘寿命要求地球形成非常迅速。我们表明，年轻，遥远的集群（$ \ leq $ 5 MYR，$> $ 200 PC）经常主导这类研究。这样的簇经常受到限制的幅度，导致高质量恒星的占代表性过高。随着高质量恒星较早地分散磁盘，衍生的磁盘寿命最适用于高质量恒星而不是低质量恒星。仅包括附近的集群（$ <$ 200 PC）可以最大程度地减少限制幅度的效果。在这种情况下，低质量恒星的中位磁盘寿命为5-10 MYR，因此比频繁声称的要长得多。较长的时间尺度为行星提供了充足的形式时间。下一个巨大的挑战比低质量恒星要快得多。
The lifetime of protoplanetary disks is a crucial parameter for planet formation research. Observations of disk fractions in star clusters imply median disk lifetimes of 1 -- 3 Myr. This very short disk lifetime calls for planet formation to occur extremely rapidly. We show that young, distant clusters ($\leq$ 5 Myr, $>$ 200 pc) often dominate these types of studies. Such clusters frequently suffer from limiting magnitudes leading to an over-representation of high-mass stars. As high-mass stars disperse their disks earlier, the derived disk lifetimes apply best to high-mass stars rather than low-mass stars. Including only nearby clusters ($<$ 200 pc) minimizes the effect of limiting magnitude. In this case, the median disk lifetime of low-mass stars is with 5 -- 10 Myr, thus much longer than often claimed. The longer timescales provide planets ample time to form. How high-mass stars form planets so much faster than low-mass stars is the next grand challenges.
