Facility Support: The Purdue Rare Isotope Measurement Laboratory

虽然宇宙射线产生的核素在地球表面过程中的应用相对较新，但这些研究的影响是惊人的。十年前，很难在与地貌相关的时间尺度上测量景观的侵蚀速率；当时的测量方法很少，而且往往不可靠。今天，整个流域的侵蚀速率可以用宇宙成因的10Be和26Al来测量，几乎是常规的，通过测量它们在河流沉积物中的浓度。这些研究的初步成功预示着宇宙核素应用的巨大增长。宇宙起源放射性核素的测量是用加速器质谱法完成的。AMS是一种越来越重要的工具，被应用于跨越众多地球科学学科的各种研究问题。AMS的独特优势在于它能够测量丰度比在10-12到10-15之间的元素的同位素。AMS最常测量的核素包括10Be、14C、26Al、36Cl和129I。这些和其他放射性核素是在各种地质环境中产生的；它们的浓度可以作为自然发生过程的计时器或示踪剂。随着美国国家科学基金会科学界对AMS测量的需求增加，PRIME实验室必须能够满足这一需求，并在测量能力和科学应用方面发挥领导作用。PRIME实验室的最终目标是成为美国地球科学中AMS放射性核素测量和应用的焦点。在过去的几年中，已经完成了许多升级。这些增强功能可以实现更高的精度和更快的测量。在接下来的四年中，我们预计现有度量能力的改进和新能力的开发。AMS技术的这些发展将与宇宙核素在地球科学中的新应用同步进行。

EAR-0452936CaffeeAlthough the application of cosmic-ray-produced (cosmogenic) nuclides in earth surface processes is relatively new, the impact of these studies is astonishing. Ten years ago it was difficult to measure the erosion rate of a landscape over a timescale relevant to geomorphology; few measurements existed, and these were often unreliable. Today, basin-wide erosion rates can be measured with cosmogenic 10Be and 26Al, almost routinely, by measuring their concentrations in stream sediment. The initial success of these studies portends an immense growth in the application of cosmogenic nuclides. The measurement of cosmogenic radionuclides is accomplished using accelerator mass spectrometry (AMS). AMS is an increasingly important tool that is applied to a variety of research problems spanning numerous earth science disciplines. The unique strength of AMS is its ability to measure isotopes of an element in which the abundance ratios range from 10-12 to 10-15. The nuclides most commonly measured by AMS include 10Be, 14C, 26Al, 36Cl, and 129I. These and other radionuclides are produced in a variety of geologic settings; their concentrations can serve as chronometers or tracers of naturally-occurring processes. As demand in the NSF scientific community for AMS measurements increases PRIME Lab must be able to meet this demand and assume leadership in both measurement capabilities and scientific applications. PRIME Lab's ultimate goal is to be the focus point for the measurement and application of AMS radionuclides in Earth sciences in the U.S. During the last several years numerous upgrades have been completed. These enhancements are enabling higher precision and faster measurements. During the next four years we anticipate both improvements in existing measurement capabilities and the development of new capabilities. These developments in AMS technology will proceed in parallel with new application of cosmogenic nuclides in the Earth sciences.