Demonstration of a Generic Local Oscillator System for ALMA Band 2+3

阿塔卡马大型毫米/亚毫米阵列（阿尔马）是一个在毫米和亚毫米波长范围内运行的世界级天文观测台。它为天文学家提供了前所未有的空间分辨率和灵敏度的观测工具。阿尔马将允许调查与恒星和行星形成有关的基本过程，以及银河系和银河系外的演变，彻底改变我们对宇宙如何演变的理解。英国科学技术设施理事会理事会（STFC）早就认识到阿尔马在其战略科学计划中的重要性，并通过其成员资格和对欧洲南方天文台（ESO）的支持支持其发展和建设，ESO在欧洲范围内领导阿尔马项目。阿尔马现在是一个功能性仪器，正在提供高水平的科学。然而，它并不完整，需要进行重要的技术升级，才能充分发挥其最初计划的潜力。例如，虽然阵列的主要生产阶段已经成功完成，科学回报已经开始，但阿尔马目前缺乏拟议的全频率覆盖，这限制了其观测能力。通过欧洲南方天文台（ESO）授予英国的先前赠款，曼彻斯特大学在新的阿尔马接收器波段的概念开发阶段领导了一个欧洲财团设计研究小组，该波段既扩展了阵列的工作频率，使其包括波段2，又通过与现有波段3同时合并来提高工作效率。新的接收器波段目前被指定为波段2+3，本提案的目标是开发关键和相关的波段2+3系统技术，为实现新的阿尔马探测设施迈出重要的一步。因此，我们现正寻求项目研究及发展资源，以支援为期21个月的技术发展活动，透过生产和测试核心技术，即一个新的通用本振，为新频带2+3奠定基础。在我们的项目过程中，我们还将展示增强型低噪声放大器（LNA）技术，并证明一个相关的关键信号混频下变频级。因此，我们工作方案的一个核心目标是确保阿尔马项目通过将其技术准备状态从目前的3级提高到接近6级的更高水平，将2+3级作为一个技术概念。随后将进行ESO资助的原型设计和部署阶段，将在10年内完成。我们的活动将意味着阿尔马获得更大的观测能力和更好的运营基础设施;欧洲南方天文台处于一个非常有利的位置，在国际阿尔马项目中领导新的接收机概念，英国保证在未来的原型和全面生产计划中获得领先的技术作用，这也为英国的工业参与提供了巨大的潜力。

The Atacama Large Millimeter/sub-millimeter Array (ALMA) is a world-class astronomical observatory operating in the millimetre and submillimetre wavelength range. It provides astronomers with an observing tool of unprecedented spatial resolution and sensitivity. ALMA will allow investigation of fundamental process associated with stellar and planetary formation, and galactic and extra-galactic evolution, revolutionising our understanding of how the Universe evolves. The UK Science and Technology Facilities Council (STFC) has long recognised the importance of ALMA within its strategic science plan, and has supported its development and construction through its membership of, and support for, the European Southern Observatory (ESO), which provides leadership of the ALMA project within Europe.ALMA is now a functional instrument and is delivering high-grade science. However, it is not complete, and important technical upgrades are needed before it can reach its full, and originally planned, potential. For example, although the main production phase of the array has been successfully completed, and the return of science has already begun, ALMA presently lacks its proposed full frequency coverage and this is limiting its observational capability. Through a previous grant awarded to the UK by the European Southern Observatory (ESO), the University of Manchester has led a European consortium design study group during the conceptual development phase of a new ALMA receiver band, which both extends the operational frequency of the array to include Band 2, and provides increased operational efficiency through a simultaneous merger with the pre-existing Band 3. The new receiver band is currently designated Band 2+3, and it is the objective of this proposal to develop key and related Band 2+3 systems technology that provide a vital step towards its realisation as a new ALMA detection facility. We are therefore seeking Project Research and Development (PRD) resource to support a 21-month technical development activity that will establish the foundations of the new Band 2+3 through the manufacture and test of core technology, viz. a new and generic local oscillator (LO). During the course of our project, we will also demonstrate enhanced low noise amplifier (LNA) technology and prove a related, and critical, signal frequency mixing down-conversion stage. A core objective of our programme of work is therefore to ensure that Band 2+3 is adopted as a technical concept by the ALMA Project through the raising of its technical readiness status from a current level of 3, to a significantly higher level approaching that of 6. This would be followed by an ESO funded prototyping and deployment phase to be completed within a 10-year timescale. Our activity will mean that ALMA gains increased observational capacity and improved operational infrastructure; ESO is placed in an excellent position to lead the new receiver concept within the international ALMA Project, and the UK is assured of gaining a leading technical role in a future prototype and full production programme, which also offers excellent potential for significant UK industrial involvement.