The Union College Ion-Beam Analysis Laboratory


Union College obtained it's first nuclear particle accelerator in about 1965 with a grant from the Atomic Energy Commission. Professors Goble, Schwarz, and Pilcher were instrumental in writing the proposal and getting the machine installed. It was a High Voltage Engineering 400 KeV Van de Graaff machine capable of currents in excess of 100 micro-amperes. The original purpose was to accelerate deuterons into a tritium target, and so produce 14 MeV neutrons. The neutrons were used to study short-half life isotopes.

Professor Christopher Jones took over the machine in about 1970, and focus shifted to other uses such as PIXE (proton induced x-ray emission spectroscopy), elastic scattering, and occasionally channeling and RBS (Rutherford backscattering spectroscopy) studies. We had a lot of fun with that accelerator over the years. Many students did senior projects ranging from the development of auxiliary circuits to channeling to PIXE.

Recognizing the shortcomings of using 400 KeV protons (in particular for PIXE and RBS work), the department decided in about 1990 to acquire a new accelerator. The effort was spearheaded and the proposal was written by David Peak. Some college funds were used to match NSF funds, and so we were successful in getting the new accelerator installed.

In 2003, Prof. Scott LaBrake acquired the lab and a conerted effor was made to use the accelrator as a major teaching and research tool. Prof. Mike Vineard joined the group in 2008 to further expand our teaching and research capabilities from his expertise and work at the Thomas Jefferson National Accelerator Facility (JLab).

We routinely use the the accelerator to do either a Proton Induced X-ray Emission (PIXE) spectroscopy experiment involving elemental identification of environmental samples in our first year seminar (PHY100) class and then revisit the same experiment in our upper level laboratory couse (PHY300) where we add concentrtation measuremens to elemental identification of envirnmental samples. Other times, we will do a Rutherford Backscattering (RBS) experiment to identify elements in a thin film target (PHY100) and then revisit the experiment (PHY300) to determine thin film thicknesses, energy loss in materials, enery straggle, or general scattering experiment in which the angular distribution of the scattered particles (protons or alpha particles) are measured.

In addition, we use the accelerator as part of our annual (in our 11th year) Physical Constants Workshop for Teachers and Students. Area high school teachers and select students from their classes spend a day at Union College in the Department of Physics & Astronomy performing experiments do determine a number of physical constants from famous experiments and performing experiments of a general nature. Experiments are routinely performed using either RBS or PIXE. Most measuremnts in recent years have involved the elemental identification of a set of thin-target, single-element standards as well as several real samples taken from the environment.

The current state of the lab involves using the accelerator to teach and to engage students in undergraduate research in Physics. Currently we employ applications of nuclear physics to environmental problems. This involves the study of environmental materials using ion-beam analysis (IBA) techniques such as PIXE, PIGE, RBS, and ERDA with the 1.1-MV tandem Pelletron accelerator. We routinely send our students to professional meetings and conferences including the Conference on the Applications of Accelerators in Reaearch and Industry (CAARI), the American Physical Society's Division of Nuclear Physics (APS DNP) fall meetings, as well and the American Physical Society's New York State Section meetings.