Laboratory Astrophysics: Spectroscopy of astrophysically important elements and applications to astrophysics

行星大气层和恒星的光谱通常非常复杂：周期表中的所有元素都可能有贡献，因为分子或原子在不止一个电离阶段，几条谱线的混合是规则而不是例外。地面和空间望远镜上的新的高分辨率光谱仪给出了令人兴奋的恒星和行星大气的光谱，但是对于解释天体物理光谱至关重要的实验室原子数据和原子物理学（原子能级，波长等）往往太不准确和不完整。在许多情况下，对原子光谱的认识和理解需要巨大的改进。空间和大气物理小组的光谱实验室有一台傅里叶变换光谱仪，它是独一无二的-保持着同类仪器的短波长记录，并且具有非常高的分辨率和广泛的光谱范围，是研究可见光到紫外光谱范围内天体物理学重要原子和离子的理想选择。一旦在实验室中记录了原子光谱，就会对光谱进行分析，以前所未有的精度在广泛的光谱范围（红外线到紫外线）内产生新的原子参数。这给原子物理学带来了新的认识。我们在新的原子数据的应用方面进行国际合作。例子包括我们的工作盖亚- ESO调查100，000 s银河系恒星，以了解银河系的演变。这个STFC资助的博士学位。该项目将利用高分辨率光谱学研究在天体物理学上具有重要意义的原子光谱。将仔细挑选与天体物理学应用最相关和最迫切需要的光谱进行研究。该项目的初始阶段是实验性质的，在帝国理工学院研究紫外和可见光谱区的光谱，并在红外线可能在国家标准与技术研究所（美国）或隆德大学（瑞典），我们经常与他们合作。然后学生将对光谱进行全面的分析。我们期望在分析阶段与理论原子物理小组合作。新的原子数据将通过与天文学家的合作应用于具体的天体物理光谱分析。我们最近的研究的例子包括与团队合作，调查不同的主题，如银河系的演变，基本常数的时间变化，并了解中子星星合并。

The spectra of planetary atmospheres and stars are usually extremely complex: all the elements of the periodic table may contribute, as molecules or atoms in more than one stage of ionisation, blends of several lines are the rule rather than the exception. New high-resolution spectrographs on ground- and space-based telescopes give exciting spectra of stars and planetary atmospheres, but the laboratory atomic data and atomic physics (atomic energy levels, wavelengths etc) that are vital for the interpretation of the astrophysical spectra, are often too inaccurate and incomplete. Vast improvements are needed in many cases in knowledge and understanding of atomic spectra. The Space & Atmospheric Physics group's Spectroscopy Laboratory has a Fourier Transform spectrometer which is unique - holding the short wavelength record for an instrument of its kind, and with its very high resolution and broad spectral range is ideal for studies of astrophysically important atoms and ions in the visible to ultraviolet spectral range. Once an atomic spectrum has been recorded in the laboratory, an analysis of the spectrum is carried out to yield new atomic parameters over a broad spectral range (infra-red through to ultraviolet) at unprecedented accuracy. This brings new understanding of the atomic physics. We collaborate internationally on applications of the new atomic data. Examples include our work on the Gaia- ESO survey of 100,000s Galactic stars to understand Galactic evolution. This STFC funded Ph.D. project will investigate astrophysically important atomic spectra using high-resolution spectroscopy. Spectra to be studied will be carefully selected to be most relevant and urgently needed for astrophysics applications. The initial stage of the project is experimental in nature with spectra being studied in the UV and visible spectral region at Imperial College, and in the infra-red possibly at the National Institute of Standards and Technology (USA) or in Lund University (Sweden), with whom we regularly collaborate. The student will then undertake a full analysis of the spectra.We anticipate collaboration with theoretical atomic physics groups during the analysis stage. The new atomic data will then be applied in particular astrophysical spectral analyses through collaboration with astronomers. Examples of our recent research include working with teams investigating topics as diverse as Galactic evolution, time variation of the fundamental constants, and understanding neutron star mergers.