Development of Sub-Millimetre Heterodyne Array & Probing the Interstellar Medium of Nearby Galaxies with JWST and ALMA

亚毫米外差阵列的研制

• 批准号: 2888233
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2888233
• 关键词: Development; Sub; Millimetre; Heterodyne; Array

This D.Phil. programme is comprising two complementary science topics: A focus on the development of the sub-millimetre quantum detector, and an observation project utilising mid-infrared (MIR) data from JWST and ALMA.The physical and chemical conditions in star-forming regions can be determined by observing at millimetre and sub-millimetre wavelengths, where a host of atomic, ionic and molecular lines can be found. In recent years, spectroscopic and interferometric observations of these lines have refined our knowledge of the gas dynamics and kinematics of nearby and distant galaxies, as well as enabling the first direct detection of black hole images. These observations have only been possible because of the extraordinary characteristics of near quantum-noise-limited Superconductor-Insulator-Superconductor (SIS) heterodyne receivers. SIS mixers are used routinely on observatories such as the Northern Extended Millimetre Array (NOEMA), the Atacama Large Millimetre/sub-millimetre Array (ALMA), and the Herschel space observatory, to name a few, enabling numerous observations of faint objects with high spectral and spatial resolution. However, there is a major limitation in utilising SIS receivers for near future astronomical observation, either ground-based or space-borne.Traditional high spectral resolution observations demand excessive telescope time. This hampers important scientific programs, especially when complementing large-area continuum mapping data done by e.g., bolometric arrays on Herschel which lack of dynamic and kinematic information, or science that require large area high spatial and spectral resolution. Improving mapping speed entails increasing the number of detectors and/or enhancing sensitivity. However, most existing sub-mm instruments fall short of reaching the ultimate quantum limit, crucial for imaging high-z galaxies and black holes. Additionally, these instruments often possess a limited number of spatial pixels, making mapping large structure within the Galactic plane and nearby galaxies a formidable challenge.A new generation of ultra-sensitive wide-field infrastructure is now required e.g., the planned ground-based (e.g., AtLAST, LST) and space-based (e.g., NASA Probe) telescopes, that are expected to be equipped with large pixel count heterodyne arrays (~103 pixels) and must be built whilst retaining extraordinary levels of individual-pixel sensitivity. It is only possible to plan the construction of large instruments with confidence, once the needed technology has been developed to high TRL, including smaller-scale demonstration on existing telescopes. This D.Phil. project therefore aim to address these challenges by developing a small-pixel count sub-millimetre heterodyne array, involving advancing techniques at every stage, making them modular and array-able, with an eye towards enabling the future deployment of kilo-pixel receivers. The project targets to demonstrate the technologies by developing a dual-polarisation sub-millimetre heterodyne demonstrator, which would retain the full astronomical signal strength and preserve the polarisation information. For the scientific observation part, the student will focus on an investigation of the Interstellar Medium of a sample of nearby galaxies using data from the James Webb Space Telescope (JWST) Mid-Infrared Spectrometer (MIRI) and the Atacama Large Millimetre Array (ALMA). The advent of JWST has provided us with unprecedented sensitivity and spatial resolution to enable studies of the properties of the ISM in a spatially resolved manner in galaxies near and far. The project will focus on a sample of nearby galaxies and will examine, for the first time, element abundances based on mid-infrared (MIR) ionic lines which are unaffected by temperature dependencies and therefore will deliver robust estimates of metallicity gradients. Furthermore, the student will compare the distribution of molecular gas (often used to trace the raw ma

这个d.phil。计划包括两个互补的科学主题：关注次数量子探测器的开发，以及使用JWST和ALMA的中海数据（MIR）数据的观察项目。通过在毫米和亚毫米的波长下观察，可以找到许多原子，离子和分子线。近年来，这些线的光谱和干涉测量值完善了我们对附近和遥远星系的气体动力学和运动学的了解，并启用了黑洞图像的首次直接检测。这些观察结果仅是由于近量子噪声限制的超导体 - 绝缘体 - 驱动器（SIS）异差接收器的非凡特征。 SIS搅拌机通常用于诸如北部扩展毫米阵列（NOEMA），ATACAMA大毫米/sub-millimetre阵列（Alma）和Herschel空间天文台等观测站中，以示例数量，使许多具有较高的微弱对象的观察值光谱和空间分辨率。但是，利用SIS接收器进行不久的将来的天文观察，无论是地面或太空传播。传统的高光谱分辨率观察都需要过多的望远镜时间。这妨碍了重要的科学计划，尤其是在补充大面积连续图映射数据时，例如，Herschel上缺乏动态和运动学信息的Bolometric阵列或需要大面积的高空间和光谱分辨率的科学。提高映射速度需要增加检测器的数量和/或提高灵敏度。但是，大多数现有的亚MM仪器都无法达到最终的量子极限，这对于成像高Z星系和黑洞至关重要。此外，这些仪器通常具有有限数量的空间像素，使银河平面和附近星系中的大型结构成为巨大的挑战。例如，ATLAST，LST）和空间基（例如NASA探针）望远镜，预计将配备大型像素计数杂种阵列（〜103像素），并且必须构建，同时保持非凡的单个像素敏感性。只有一旦开发出高度TRL的技术，就可以自信地计划大型乐器的建设，包括现有望远镜上的较小规模的演示。这个d.phil。因此，项目的目的是通过开发一个小像素计数子毫米杂质阵列来应对这些挑战，涉及每个阶段的提高技术，使其成为模块化和可阵列，并着眼于使未来的基洛像素接收器的部署。该项目的目标是通过开发双极化亚毫米近差示威者来证明技术，该杂物将保留完整的天文信号强度并保留极化信息。对于科学观察部分，学生将使用James Webb太空望远镜（JWST）中边红外光谱仪（MIRI）和Atacama大毫米阵列（ALMA）的数据来研究附近星系样本的星际介质。 JWST的出现为我们提供了前所未有的灵敏度和空间分辨率，以在附近的星系中以空间解析的方式研究ISM的性质。该项目将集中在附近星系的样本上，并将首次检查基于中红外（miR）离子线的元素丰度，这些元素丰度不受温度依赖性的影响，因此将提供金属梯度的强大估计值。此外，学生将比较分子气的分布（通常用于追踪原始MA