A study of extreme extra-solar planetary systems

检查被金属污染的大气层的白矮星是测量系外行星体组成的一种途径，为我们理解行星形成提供了重要的信息。盖亚太空任务的数据将是将已知白矮星数量增加一个数量级的关键，第一次重大数据发布计划于2018年4月发布，从而可以得出大样本统计数据。该项目的重点是识别和分析受污染的白矮星，以调查太阳系外系统中岩石天体的化学成分。我们将对69颗白矮星使用紫外线光谱，这是作为HST快照计划的一部分记录下来的，然后将该项目扩大到包括Gaia DR2目标。还将分析使用下一代仪器Weave和DESI收集的地面光谱学。随后，我们将研究作为白矮星质量(因此是前身行星宿主的质量)和冷却/系统年龄的函数的丰度趋势-当前的工作可能受到少数可用目标的限制-以调查星系演化对行星外系统形成的影响。

Examining white dwarfs with metal-polluted atmospheres is a route to measuring the bulk composition of exo-planetesimals, providing important input into our understanding of planet formation. Data from the Gaia space mission will be the key to increase the number of known white dwarfs by an order of magnitude, with the first major data release planned for April 2018, allowing large-sample statistics to be derived. This project is focussed on identifying and analysing polluted white dwarfs to investigate the chemical composition of rocky bodies in extrasolar systems. We will use ultraviolet spectroscopy for 69 white dwarfs, recorded as part of a HST Snapshot program, before expanding the project to include Gaia DR2 targets. Ground-based spectroscopy collected using the next-generation instruments WEAVE and DESI will also be analysed. We will subsequently examine trends in abundances as a function of white dwarf mass (and hence mass of the progenitor planet host) and cooling/system age - current works may have been limited by small numbers of available targets - to investigate the effects of galactic evolution on the formation of exo-planetary systems.