Track 2 MRI: Acquisition of a Mini Carbon Dating System for Multi-Millennial, Multi-User Sequences of Annually Resolved 14C and Other High Precision Applications

该主要研究仪器（MRI）计划奖提供资金，以支持购买用于测量植物，动物和一些无机样品中碳-14（14 C或放射性碳）含量的仪器。碳-14是碳的不稳定同位素，可用作“放射性时钟”，以确定过去4万年来一系列样本的日期。虽然放射性碳测年是最广泛使用的工具，用于确定影响人类历史的事件的变化率和时间，但锁定在自然档案中的碳-14也为一些关键的科学前沿提供了重要的见解。其中包括：重建过去全球范围的大气和海洋环流变化;预测和缓解威胁空间天气事件的技术;了解太阳强迫对气候的作用;通过使用全球检测到的碳-14标记事件，同步全球范围的人类，气候和生态变化年表。该仪器将被纳入世界上最早的树轮研究实验室（LTRR）的教学、公共宣传和研究方案，该实验室自1960年代开始使用放射性碳测年技术以来，一直与该技术交织在一起。这提供了独特的机会，通过以新的方式结合这两种测年和古环境重建方法来加强和扩大STEM的推广和教学，以引入核心科学概念，讲述科学故事，并激发碳14分析前沿的新实验和应用。Ionplus AG的微型碳定年系统（MICADAS）的购买将最大限度地提高稳定、高精度、小样本的通量，（50-500微克）的碳-14测量，适用于需要快速处理数千个样品的应用，例如对单个树木年轮进行连续测量。MICADAS将与自动石墨化设备（AGE 3）系统和同位素比质谱仪（IRMS）相结合，以促进更快的样品制备和有效的通量。在LTRR的安装将为当地，国家和国际用户社区提供一个服务中心，在一个屋檐下提供树木年轮和放射性碳定年解决方案，并创造新的现场和远程培训机会，融合了树木年轮，时间顺序和放射性碳方法的专业知识。启动研究重点将;继续开展工作，推动国际社会努力重建国际放射性碳校准曲线现有的基于树木年轮的部分（任何使用放射性碳测定样品年代的人都需要）使用单一的树木年轮样品;努力建立可能威胁现代基础设施的过去空间天气极端事件的周期性和严重程度的基线;提供全新世期间太阳对气候作用力的年度解析代理记录;揭示“宇宙成因锚点”，以同步不同的代理记录，如冰芯和树木年轮记录;探索碳循环的全球和区域变化;通过比较树木年轮和每年层积的海洋双壳类的碳-14时间序列，评估关键气候带的海洋环流。 该设施将通过一系列讲习班、暑期学校、奖学金方案和网络资源，提供有针对性的跨学科培训机会（地方、国家和国际），以满足在使用树木年轮测年技术和放射性碳分析的综合应用方面日益增长的特殊培训需求。该仪器的可访问性，高容量和吞吐量，以及样品制备要求也将提供出色的教学和培训机会，使本科生和研究生STEM学生，早期职业研究人员和亚利桑那大学的教师（一个赠地，西班牙裔服务机构，女性学生占52%）受益。将仪器和相关的核心科学概念整合到一个蓬勃发展的推广计划中，该计划覆盖区域标题1学校，并为c。每年2,500名参观者，将确保新设施不仅是产生新的交叉研究应用的纽带，而且是激励下一代STEM科学家的地方，并向公众介绍科学用于测量时间和探索地球过去的方式，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Major Research Instrumentation (MRI) Program award provides funds to support the acquisition of an instrument with which to measure the amount of Carbon-14 (14C or radiocarbon) in plants, animals and some inorganic samples. Carbon-14 is the unstable isotope of carbon and can be used as a ‘radioactive clock’ to date a range of samples from the last 40+ thousand years. While radiocarbon dating is the most widely used tool with which to determine rates of change and the timing of events which impacted human history, Carbon-14 locked away in natural archives such as tree-rings also offers important insights into a number of key scientific frontiers. These include: reconstructing past global scale changes in atmospheric and oceanic circulation; predicting and mitigating for technology threatening space weather events; understanding the role of solar forcing on climate and; synchronizing global scale chronologies of human, climate and ecological change through the use of globally detected Carbon-14 marker events. The instrument will be integrated into the teaching, public outreach and research programs of the world’s founding Laboratory of Tree-Ring Research (LTRR), which has interwoven with radiocarbon dating since inception of the technique in the 1960s. This provides unique opportunities to enhance and broaden STEM outreach and teaching by combing these two dating and paleoenvironmental reconstruction methods in new ways to introduce core scientific concepts, tell science stories, and inspire new experimentation and applications at the cutting edge of Carbon-14 analysis. This will be accelerated by the proximity of the instrument to an archive of millions of ready-to-analyze, unique, annual-scale Carbon-14 samples housed in LTRR.The purchase of Ionplus AG’s Mini Carbon Dating System (MICADAS) will maximize throughput of stable, high-precision, small-sample (50–500 microgram) measurements of Carbon-14 for applications that require rapid throughput of thousands of samples, such as consecutive measurements from individual tree-rings. The MICADAS will integrate with an Automated Graphitization Equipment (AGE3) system coupled with an Isotope Ratio Mass Spectrometer (IRMS) to facilitate speedier sample preparation and efficient throughput. Installation in LTRR will provide a service center for a local, national, and international user community by offering tree-ring and radiocarbon-dating solutions under one roof, and creating new onsite and remote training opportunities with converging expertise in tree-ring, schlerochronological, and radiocarbon methods. Starting research foci will; continue in progress work towards an international community effort to rebuild the existing tree-ring based portion of the International Radiocarbon Calibration Curve (required by anyone dating samples using radiocarbon) using single tree-ring samples; work to establish baselines for the periodicity and magnitude of past space-weather extremes which could threaten modern infrastructure; provide an annually resolved proxy record of solar forcing on climate through the Holocene; reveal “cosmogenic anchor points” to synchronize disparate proxies such as ice-core and tree-ring records; explore global and regional variability in carbon cycling and; assess ocean circulation in critical climatic zones through comparison of Carbon-14 time-series from tree-rings and annually laminated marine bivalves. The facility will respond to an increasing need for niche training in combined applications using tree-ring dating techniques and radiocarbon analysis by offering targeted interdisciplinary training opportunities (locally, nationally and internationally) through a range of workshops, summer schools, scholarship programs and web-resources. The instrument’s accessibility, high capacity and throughput, plus sample preparation requirements will also provide outstanding teaching and training opportunities to benefit undergraduate and graduate STEM students, early-career researchers, and faculty at the University of Arizona (a land-grant, Hispanic Serving Institution with a 52% female student population). Integration of the instrument and associated core scientific concepts into a thriving outreach program, which reaches regional Title 1 schools and serves c. 2,500 visitors a year, will ensure that the new facility not only functions as a nexus to generate new-cross-cutting research applications, but also as a place to inspire the next generation of STEM scientists and to inform the public about the ways science is used to measure time and explore Earth’s past, present and future.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.