The stellar initial mass function

星星形成的结果是恒星和具有一定质量范围的亚恒星物体。天体物理学家将质量的分布称为初始质量函数（IMF）。IMF与恒星形成率的时间调制一起决定了星系和星星团的演化和命运，因此是最基本的天体物理分布函数之一。尽管它的重要性，尽管非常大的研究工作取得了重大进展，我们仍然不知道IMF的确切形状，也没有明确的证据表明IMF的变化与恒星形成的条件被发现。一种新的迭代方法是适用于提取的IMF的形状非参数从观测到的恒星光度函数（恒星光度的分布函数），由于未解决的多个系统的偏差是量化的大质量恒星。另一个目标是研究溶解的星星团如何影响IMF的测量，以及包括棕矮星和观测到的行星在内的亚恒星物体的起源。

The outcome of star formation are stars and sub-stellar objects with a range of masses. Astrophysicists refer to the distribution of masses as the initial mass function (IMF). The IMF together with the time-modulation of the star-formation rate dictates the evolution and fate of galaxies and star clusters, and is therefore one of the most fundamental astrophysical distribution functions. Despite its importance, and despite a very large research effort with significant advances, we still do not know the exact shape of the IMF, nor has unambiguous evidence for a variation of the IMF with star-forming conditions been found. The project outlined here addresses both these important issues. A novel iterative method is to be applied to distill the shape of the IMF non-parametrically from an observed stellar luminosity function (the distribution function of stellar luminosities), and the bias due to unresolved multiple systems is to be quantified for massive stars. Another aim is to investigate how dissolving star clusters affect the measurement of an IMF, and what the origin of sub-stellar objects including brown dwarfs and the observed planets may be.