Low Mass Companions of White Dwarf Stars

现代天文学中最古老的问题之一是：伴随行星系统的恒星的百分比是多少？介于低质量恒星和巨大行星（如木星）之间的桥梁是一类被称为“褐矮星”的物体。褐矮星从缓慢的引力收缩释放的能量中发出红外（IR）波长的光。在接下来的三年里，首席研究员（PI）和他的合作研究员将继续进行一项长期的、以前由美国国家科学基金会支持的调查，以寻找褐矮星。由于褐矮星并不比白矮星暗太多，他们将用红外相机获得几百颗白矮星的电子图像，并估计其中褐矮星的数量。他们还将继续监测先前发现的褐矮星/白矮星系统，以确定它们的轨道特征，并最终确定这些物体的质量。预计这项研究和相关研究将对我们理解恒星和行星的形成，特别是所有这些物体是否都是同一形成过程的产物，做出重大贡献。

One of the oldest questions in modern astronomy is: what is the percentage of stars accompanied by planetary systems? The bridge between low-mass stars and giant planets, such as Jupiter, is a class of objects called "brown dwarfs." Brown dwarfs shine at infrared (IR) wavelengths from energy released by slow gravi- tational contraction. During the next three years the Principal Investigator (PI) and his Co-Investigator will continue a long-term and previously NSF-supported survey to search for brown dwarfs. Because brown dwarfs are not too much fainter than white dwarfs, they will obtain electronic images of several hundred white dwarfs with an IR camera and estimate the number of brown dwarfs among them. They will also continue to monitor previously discovered brown-dwarf/white-dwarf systems to determine their orbital charac- teristics and ultimately the masses of these objects. It is expected that this and related studies will contribute significantly to our understanding of the formation of stars and planets, and in particular whether all these objects are products of the same formation process.