Scott LaBrake

Construction of a scattering chamber for ion-beam analysis of environmental materials in undergraduate physics research

We have developed a new scattering chamber for ion-beam analysis of environmental materials with the 1.1-MV Pelletron accelerator at the Union College Ion-Beam Analysis Laboratory. The chamber was constructed from a ten-inch, Conflat, multi-port cross and includes a three-axis target manipulator and target ladder assembly, an eight-inch turbo pump, an Amptek X-ray detector, and multiple charged particle detectors. Recent projects performed by our undergraduate research team include proton induced X-ray emission (PIXE) and Rutherford backscattering (RBS) analyses of atmospheric aerosols collected with a nine-stage cascade impactor in Upstate New York. We will describe the construction of the chamber and discuss the results of some commissioning experiments.

Using PIXE To Teach Materials Analysis At Union College

Particle Induced X‐ray Emission (PIXE) spectroscopy, an ion‐beam analysis technique, is a powerful tool for studying the environment. The Union College Ion‐Beam Analysis Laboratory (UC–IBAL) provides a small group of students opportunities to explore experimental physics and complement their classroom training, by studying atmospheric aerosols and liquid precipitation from upstate New York using a tandem electrostatic particle accelerator. The students learn how to operate the accelerator and gain valuable laboratory skills in sample collection and preparation procedures and data acquisition and analysis techniques, as well as presentation skills.

PIXE Analysis of Synthetic Turf

We performed a proton-induced X-ray emission (PIXE) analysis of synthetic turf blade and crumb rubber infill samples to search for heavy metals and other possibly toxic substances. Samples were collected from eight FieldTurf athletic fields installed in the Capital District of New York between 2009 and 2016. The samples were bombarded with proton beams from the 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory and the emitted X-rays were measured using a silicon drift detector with an energy resolution of about 130 eV. All of the infill samples contained Zn at levels above soil standards. Approximately 17% of the infill samples contained measurable concentrations of Pb and one had a level (110 ± 10 ppm) exceeding soil standards. Bromine was detected in approximately 42% of the infill samples with a maximum concentration of 1500 ± 200 ppm and may be due to the presence of brominated flame retardants. The distributions and relative concentrations of elements measured in synthetic turf blade samples of different colors are indicative of the metal-oxide pigments used to color the blades. For example, V and Bi observed in yellow blade samples are from the environmentally friendly, yellow pigment bismuth vanadate.