分子团掩盖了他们的恒星形成效率每自由落体时间：我们可以做什么不被愚弄
Molecular clumps disguising their star formation efficiency per freefall time: What we can do not to be fooled
摘要：
与气体密度均匀的情况相比，分子团中体积密度梯度的存在使它们能够提高恒星形成率。这种更高的恒星形成率反过来又会产生我们测量的每自由落体时间的恒星形成效率的更高值。因此，所测量的每自由落体时间$ε_{\rm ff, meas}$的星团恒星形成效率受到简并性的困扰，因为有两个因素对它起作用：一个是星团气体的密度梯度，另一个是每自由落体时间$ε_{\rm ff, int}$的固有恒星形成效率，如果没有气体密度梯度，星团将形成恒星。本文提出了一种方法，允许一个恢复的内在效率的集中丛。它取决于从团中心到团边缘局部测量的恒星和气体表面密度之间的关系。不需要了解团簇气体的初始密度分布。对该方法的逐步说明是观察者手中的一个工具。一旦$ε_{\rm ff, int}$被估算出来，它就可以与它的测量的、团块平均的、对应的$ε_{\rm ff, meas}$进行比较，以量化团块的初始气体密度分布对其恒星形成历史的影响。
英文摘要：
The presence of a volume density gradient in molecular clumps allow them to raise their star formation rate compared to what they would experience were their gas uniform in density. This higher star formation rate yields in turn a higher value for the star formation efficiency per freefall time that we measure. The measured star formation efficiency per freefall time $ε_{\rm ff, meas}$ of clumps is therefore plagued by a degeneracy, as two factors contribute to it: one is the density gradient of the clump gas, the other is the intrinsic star formation efficiency per freefall time $ε_{\rm ff, int}$ with which the clump would form stars should there be no gas density gradient. This paper presents a method allowing one to recover the intrinsic efficiency of a centrally-concentrated clump. It hinges on the relation between the surface densities in stars and gas measured locally from clump center to clump edge. Knowledge of the initial density profile of the clump gas is not required. A step-by-step description of the method is provided as a tool in hand for observers. Once $ε_{\rm ff, int}$ has been estimated, it can be compared with its measured, clump-averaged, counterpart $ε_{\rm ff, meas}$ to quantify the impact that the initial gas density profile of a clump has had on its star formation history.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
