MRI: Development of a Silicon Detector for Synchrotron Based X-Ray Spectroscopy, X-Ray Holography and Materials Education

Technical Abstract

Synchrotron spectroscopy has developed into a powerful approach to probe the atomic and electronic properties in materials varying from correlated electron systems to catalysts and extending to active metal sites in protein molecules. In many x-ray experiments, the detector systems currently available can not cope with the high flux of x-ray photons generated by synchrotron sources while still maintaining adequate energy resolution.

To address this and other problems, we propose to develop a new detector system which will have at least a fifty-fold increase in counting rate over existing commercial systems while maintaining the high resolution required to suppress unwanted background radiation. This will be accomplished by increasing the active element density (~400 elements), by the use of silicon drift-detector technology and a new very low-noise front-end Application Specific Integrated Circuit (ASIC), and by the application of sophisticated signal analysis techniques to enhance the suppression of unwanted signals and to provide real-time quantitative elemental mapping. The proposed project will build on the experience of the Brookhaven National Laboratory's NSLS Controls and Detectors and Instrumentation Division groups in developing monolithic x-ray detector arrays and custom integrated circuits, expertise in spectroscopy and instrument development at the New Jersey Institute of Technology and the NSLS, and expertise in x-ray holography and diffraction methods developed by the University of Tennessee.

At all levels of the construction and research conducted with this detector, graduate students will be involved. The proposed instrument will have a broad impact through the education of graduate and undergraduate students based on its use in laboratory courses. The instrument will be utilized as a chemical analysis tool in a transition metal oxide preparation and characterization workshop for Newark area high school students. This will serve to develop scientific literacy and to directly influence students from underrepresented groups to pursue careers in science.

General Abstract

Synchrotron spectroscopy has developed into a powerful approach to explore the properties of materials varying from metal oxides to catalysts and extending to protein molecules. In many x-ray experiments, the detector systems currently available are not capable of processing the signals generated by the latest generation of light sources.

We propose to develop a new detector system which will have at least a fifty-fold increase in signal processing capability while maintaining high energy resolution. This will be accomplished by increasing the number of detector elements, by the use of new detector technology, and by the application of sophisticated signal analysis techniques. The proposed project will build on the experience of the Brookhaven National Laboratory in detector arrays and integrated circuits, expertise in spectroscopy and instrument development at the New Jersey Institute of Technology and the National Synchrotron Light Source, and expertise in x-ray holography and scattering methods developed by the University of Tennessee.

At all levels of the construction and research conducted with this detector, graduate students will be involved. The proposed instrument will have a broad impact through the education of graduate and undergraduate students based on its use in laboratory courses. In addition, the instrument will be utilized as a chemical analysis tool in a transition metal oxide preparation and characterization workshop for Newark area high school students. This will serve to develop scientific literacy and to directly influence students from underrepresented groups to pursue careers in science.