Newton STFC-NARIT: EXOhSPEC (Exoplanet high-resolution Spectrograph)

本课题旨在实现一种常规运行的新型高分辨率光谱仪。这一概念依赖于将地球带来的复杂性与光谱仪单元本身的要求分开。这种分离使光谱仪方面的尺寸和复杂性得以大幅降低，它是Narit和其他地方正在开发的自适应光学技术的自然补充。用EXOhSPEC展示的概念可以用来为下一代超大型望远镜节省数千万英镑的仪器成本，而且大学、公共和业余天文台也可以重复使用，并提供了一种在更广泛的市场上购买大型低效傅立叶变换光谱仪的竞争性替代方案。我们希望展示的关键发展是：(1)紧凑、廉价的设计，可以在波长覆盖和光谱分辨率方面实现与现有仪器相同的性能；(2)为系统量身定做有源计量/驱动，以极小的建造和操作成本实现-甚至超过-最佳波长校准稳定性，并生产设施仪器。虽然这台仪器的原型是在赫特福德郡大学进行的，但该设备将在泰国生产，但通过在Narit总部的0.7米Astropark望远镜以及泰国国家望远镜上操作原型版本获得的洞察力。泰国政府对泰国国家天文研究所进行了大量投资，因此他们有了新的实验室来建造仪器，还可以立即使用望远镜。目前的高分辨率光谱仪体积大、价格昂贵，有时还很难维护，而且局限于全球少数几所精英大学和实验室。此外，由于这些仪器非常昂贵，技术周期和设计变化很小，没有利用新材料和大规模生产的光学元件的巨大质量改进和成本降低的优势。我们原型的关键发现之一是，渐变折射率光纤的锥化是光纤信号的一种有效的焦点减少，不受几何光学的限制。泰国专家对此进行的优化可能会被证明是该项目的一个关键副产品。一个国家的经济发展和福利取决于关键的基础设施和劳动力的能力。在物理学领域，特别是天体物理学领域，设计和制造仪器以及测量和解释其他行星、恒星和星系中跃迁的性质的能力是理解宇宙性质的关键基石。几十年来，高分辨率光谱学一直是天体物理学的主要工具，也是推动新的基础天体物理学的动力。从发现附近恒星周围的行星到直接测量宇宙的大小。在世界范围内，长期以来，超额认购最多的望远镜仪器是高分辨率光谱仪。尽管泰国有一个大型望远镜和一些较小的望远镜，但它没有高分辨率的光谱仪。该提案旨在利用海外发展援助资金发展泰国的基础设施和能力，同时深化已经在技术和科学上富有成效的合作，并为参与该项目的英国科学家和工程师带来长期利益。

The project is to realise a new kind of high-resolution spectrograph in routine operation. The concept relies on separating the complexity introduced by Earth from the requirements of the spectrometer unit itself. This separation enables a massive reduction in size and complexity on the spectrometer side and it is the natural complement to Adaptive Optics technologies being developed at NARIT and elsewhere. The concepts demonstrated with EXOhSPEC can be used to save tens of millions of pounds in instrumentation costs on the coming generation of extremely large telescopes but also be reproducible by University, public and amateur observatories and offer a competitive alternative to the purchase of large inefficient Fourier transform spectrometers in the wider marketplace. The key developments that we wish to demonstrate are, (1) a compact inexpensive design that can achieve the same performance as existing instruments in terms of wavelength coverage and spectral resolution and (2) bespoke active metrology/actuation of the system to achieve -or even surpass- the best wavelength calibration stability at a fraction of construction and operation costs and to produce a facility instrument. While the prototyping for this instrument is at the University of Hertfordshire, the facility instrument will be produced in Thailand but with the insight gained from operating a prototype versions on the 0.7m Astropark telescope at NARIT headquarters as well at that the Thai National Telescope. The Thai government has made a large investment in the National Astronomical Research Institute of Thailand and so they have the new laboratories in which to build the instrument as well as immediate access to telescopes. Current high-resolution spectrographs are large, expensive and sometimes difficult to maintain and limited to an elite handful of universities and laboratories around the globe. Moreover, because these instruments are so expensive, technology cycles and designs have evolved very little and do not take advantage of the great quality improvement and reduced costs of new materials and mass produced optics. One of the key findings of our prototyping is that the tapering of graded-index fibres is an efficient focal reduction of fibre optic signals not limited by geometrical optics. The optimisation of this by Thai specialists may prove to be a key spinoff of the project. The economic development and welfare of a country relies on key infrastructure and the capabilities of the workforce. In the field of physics and in particular astrophysics, the ability to design and make instruments and to measure and interpret the properties of the transitions in other planets, stars and galaxies is a key cornerstone to understand the properties of the Universe. High-resolution spectroscopy has for decades being a primary tool of astrophysics and a driving force in enabling new fundamental astrophysics. From the discovery of planets around nearby stars to the direct measurement of the size of the Universe. Worldwide, the most oversubscribed instruments on telescopes have long been the high-resolution spectrographs. Although Thailand has a large telescope and a number of smaller ones it does not have a high resolution spectrograph. The proposal is aimed at using Overseas Development Aid funding to develop Thai infrastructure and capabilities while at the same time deepening a collaboration which has been already been technically and scientifically productive and also have long-term benefit to the UK scientists and engineers involved in the project.