Equipment: MRI: Track 1 Acquisition of a State-of-the-Art Electron Microprobe for Research and Training

University Of Hawaii, Honolulu

Investigators

Abstract

This award will support the acquisition of a state-of-the-art electron probe microanalyzer (EPMA) at the University of Hawaii at Mānoa. The EPMA is the gold-standard instrument for rapid determination of the abundances and distribution of elements in natural and synthetic solid materials at spatial scales from the centimeter down to the nanometer (billionth of a meter). The instrument will advance research frontiers in existing disciplinary strengths: volcanology, petrology, geochemistry, cosmochemistry, astrobiology, archeology, and planetary science. Its enhanced functionality will extend disciplinary impact to material sciences, engineering, and biological sciences, and support curricular initiatives that broaden participation of undergraduates in the UH Mānoa Earth Science and Mechanical Engineering BS degrees and the UH Hilo Anthropology program. Remote access and operation of the instrument will promote engagement of students and faculty at community colleges, scientists at the Hawaiian Volcanoes Observatory, and researchers outside Hawaii. Key capabilities of the proposed instrument include an increase in the maximum probe current, improved current stability and spatial resolution, and higher beam intensity in a small beam diameter. Specific components include (a) a thermal field emitter that provides a very high and stable probe current for ultra-high spatial resolution imaging at high and low accelerating voltage and thus, the ability to quantify light (low atomic number) elements as well as minor and trace elements; (b) a panchromatic cathodoluminescence detector that broadens the science objectives that can be addressed; (c) five wavelength-dispersive spectrometers configured with L-type diffracting crystals suitable for high beam intensities and light element detection; and (d) an advanced energy-dispersive spectrometer system for quantitative major-element mapping. Specialized software will facilitate operation by students as well as advanced researchers by streamlining background acquisition and corrections for matrix effects, spectral interferences, dead time, secondary fluorescence, and time-dependent intensities This project is jointly funded by the EAR Instrumentation and Facilities (EARIF) Program, the Established Program to Stimulate Competitive Research (EPSCoR), and Major Research Instrumentation (MRI) Program. 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.