Hope College Department of Physics and Engineering
Research Experiences for Undergraduates
Summer 2006
Project Summary

 

Project Title:

Trace Elemental Analysis Of Glass Via PIXE

Student Name: Derek Padilla (with Chris Hall)
Student's Home Institution: San Diego State
Research Advisor: Dr. Paul DeYoung and Dr. Graham Peaslee
Source of Support: National Science Foundation under Grant Numbers 0452206, 0354920 and 0319523.
Using the Hope College Ion Beam Analysis Laboratory (HIBAL), protons with an energy of 2.3 MeV are accelerated towards the prepared samples in an evacuated target chamber. Resultant x-rays are detected at 45º with a Si(Li) detector. The x-ray spectra are analyzed with the GUPIXWIN peak-fitting software which outputs relative concentrations of trace elements. With these relative concentrations, ratios between trace elements are used for the comparative aspect of the statistics. This use of ratios eliminates much systematic error that arises when trying to acquire absolute concentrations. Specific ratios between samples are compared using Z-score testing which gives a scale of the difference between the two samples for that particular elemental ratio. When comparing two hits on the same sample, there still remains a difference in the trace elemental concentrations of that same sample due to statistical errors. This difference is used as a control in our evaluations of unknown sample concentrations. To obtain reliable statistics, multiple spectra are always obtained on each sample.

*This material is based upon work supported by the National Science Foundation under NSF-REU Grant No. 0452206.
__________________________________________________________________________________________________________________________
Publications and Presentations:
"Development of an Ion Beam Analysis Method for Forensic Analysis of Glass", Richard Sampson*, Graham F. Peaslee, Paul A. DeYoung, Christopher Hall*, Derek Padilla*, and Patrick Mears*. American Academy of Forensic Sciences 2008 Annual Meeting, Denver, Colorado, (2008).

"Production of Nuclei in Neutron Unbound States via Primary Fragmentation of 48Ca", G. Christian, W.A. Peters, D. Absalon*, D. Albertson*, T. Baumann, D. Bazin, E. BreitbachI, J. Brown, P.L. Cole*, D. Denby*, P.A. DeYoung, J.E. Finck, H. Frank, A. Fritsch*, C. Hall*, A.M. Hayes, J. Hinnefeld, C.R. Hoffman, R. Howes, B. Luther, E. Mosby*, S. Mosby*, D. Padilla*, P.V. Pancella, G. Peaslee, W.F. Rogers, A. Schiller, M.J. Strongman, M. Thoennessen, and L.O. Wagner*. Nucl. Phys. A801, 101, (2008)
"Breakup of 6He Incident on 209Bi Near the Coulomb Barrier", J.J. Kolate, H. Amro, F.D. Becchetti, J.A. Brown, P.A. DeYoung, M. Hencheck, J.D. Hinnefeld, G.F. Peaslee, A.L. Fritsch, C. Hall*, U. Khadka*, Patrick J. Mears*, P. O'Rourke, D. Padilla*, J. Reith*, Tabatha Spencer, and T. Williams. Phys Rev. C 75, 031302 (2007).