Past Student WorkBrief descriptions of undergraduate student research activities are presented below. To get involved, contact me.
- Hank Donaghy ('09)
- Cameron Wales ('09)
- Rachel Dougherty ('08)
- Evan Seyfried ('08)
- Tony Ardito ('07)
- Lord Cole ('05)
- Josh Mueller ('04)
- Tyler Churchill ('03)
- James Tanyi ('01)
- Kevin Crandell ('00)
- Robert Coleman ('99)
- Eric Jensen ('98)
- Brian Champine ('97)
- Mark Skubis ('96)
- Tim Meehan ('95)
- Brian Benedict ('96)
- Matt LaBonte ('93)
- Jamie Spaman ('95)
- Brian Haas ('94)
- Andy McCartney ('92)
- Gerhard Schoenthal ('92)
- Paul Larson ('91)
HANK DONAGHY ('09) worked two semesters on the " eZapper" project during his junior year -- an electron accelerator which can be used to disable electronic devices. The first semester involved doing electron beam optics calculations for magnetic quadrupole doublets. The second semester involved writing LabVIEW vi's to control the magnetic field in the QD's and steerers.
CAMERON WALES ('09) worked two semesters during his sophomore year reconstructing the 5SDH tandem accelerator following the move back into the renovated physics building. This involved realigning and realigning the beamlines on the newly renovated non-level and non-flat floor. The last weeks entailed a study of the trace elements in various crude oils and engine oils.
RACHEL DOUGHERTY ('08) will begin a project in Fall 2007 developing the PIGE technique on the accelerator. Proton-induced g-ray production cross-sections will be measured as a function of bombarding energy for the stable oxygen and magnesium isotopes. This data will be used to determine the optimum energies at which to search for variations in isotopic abundances in samples. Analysis codes will be developed to unfold the abundances from experimental g-ray yields. The sensitivity of the technique to small variations in abundances will be analyzed.
EVAN SEYFRIED ('08) has worked on several projects in his quest to become a well-rounded nuke.
The first project in Fall 2006 involved re-establishing our ability to do PIXE with the accelerator following the building renovation. This involved making measurements on target standards and redeveloping the description of the X-ray detector lineshapes and energy-dependent efficiency. After accomplishing this he took a look at an interesting piece of ballast from the wreck of the HMS de Braak. The chunk turned out to be stibnite, Sb 2S 3, which was sold as a commodity for producing make-up, pewter, and making medicine to cure intestinal parasites.
In the spring of 2007 Evan implemented an positron annihilation lab using the Doppler shift technique and the position lifetime technique. By measuring the energies of the 511-511 annihilation photons in coincidence one can uncover information on the electron density in the conduction and valence bands of materials. The lifetime of positron is useful for determining the void fraction in materials. This is part of an interdisciplinary nuclear-condensed matter effort to study the electrical properties of polymers.
TONY ARDITO ('07) versus the Alphatross. The project began with the goal of re-instituting RBS measurement capabilities with the Alphatross source, a technique that had fallen by the wayside during the building renovation period. The battle was fierce, involving locating a modern supplier for time-delay relays, replacing rf oscillator tubes, positioning the canal and insulator, and conditioning the bottle and insulator constantly to bake out impurities. Alpha RBS were obtained, but long term stability of the bam current was not achieved. In the final weeks, Tony chugged away on Snap and studied the make-up of the clear glasses used in manufacturing the Snap bottles.
LORD COLE ('05) When he wasn't serving on special teams for the football program, Lord used PIXE to study the composition of copper alloy fasteners (commonly called bolts) used to hold 18 th century wooden ships together. The Delaware State Museum provided a couple dozen bolts from the wreck of HMB DeBraak, which sank off the Delaware coast in 1798. He made the first detailed measurements of the major and minor components of these bolts. This information provided a view into what was known about corrosion protection and active alloy development during this time period.
JOSH MUELLER ('04) began working with the 128Te angular distribution and Doppler-shift measurements in July 2001 as a rising sophomore. During the experiment he focused on gaining practical equipment knowledge such as Germanium/BGO detectors, NIM and CAMAC electronics, and accelerator operation and maintenance. In the picture at right, Josh is using his EE skills to diagnose and repair the multichannel voltmeter for the BGO phototubes. (OK, you're right, he's changing the batteries.)
During his sophomore year he worked on two projects: examining lineshapes in Si(Li) detectors, and data acquisition system development using the package KMAX. Josh transitioned our DAQ software from an older MacIIfx version of Kmax to a modern WinOS version. Josh just loves dealing with higher level routines which use C++ as their base language, just ask him. Josh defected from nuclear physics to work on a fuel cell project with Prof Edmondson his senior year. (Gee, your wouldn't think that those unprintable characters at the end of C-strings would drive you that mad.) Josh was selected as a USA Today Academic All-American ( 2004 College Academic All-Stars First Team article. He graduated in May 2004 and is currently attending Cambridge.
TYLER CHURCHILL ('03) began working in the neutron scattering business the summer after his sophomore year Traveling to the University of Kentucky, his contribution to the 126Te project was studying non-linearities of the EG&G Ortec AD114 ADC. The lifetimes of excited states of 126Te are determined by measuring Doppler shifts of the gamma rays emitted by the recoiling nuclei. Determining lifetimes down to the 1 fs range requires knowledge of the gamma ray energy to an accuracy of several parts in 10 6. An understanding of the analog-to-digital converter non-linearity is crucial. It was found that for several AD114 ADCs, the calibration could be described with a second-order fit above channel ~2000, but there exists a substantial kink in the calibration at channel ~2000 which should not be fit with a smooth function.
Tyler Churchill moved on to assume responsibility for the 130Te(n,ng) study as his senior research project. He was awarded a 'Trident Scholarship' at USNA which permitted him to use the project as a 12 credit research course each senior semester. Gamma-ray excitation functions, and angular distributions were measured following the 130Te(n,n'g) reaction on an isotopically enriched target at the University of Kentucky Nuclear Structure Laboratory during Summer 2002. Measurements entailed 3 weeks of beamtime. Approximately 170 transitions were placed into a level scheme of 101 levels up to 3.4 MeV excitation, only 48 of which were previously known. Lifetimes were extracted for ~ 50 levels. Nuclear structure interpretations are difficult near Z = 50, N = 82 as these nuclei require challenging shell model calculations with appropriate approximations. Complicated feeding patterns observed in tellurium-130 are clearly far-evolved from a vibrational structure. The strong feeding effects for many levels is reminiscent of both proton and neutron particle-hole excitations. In all the Te nuclei, the 51- and 71- levels are heavily fed. Shell model calculations by Kerek (1974) suggest these states must be formed from the coupling of the neutron hole configurations (2d 3/2 -1,1h 11/2 -1) or (3s 1/2 -1,1h 11/2 -1). Tyler reported on this project at the Philadelphia APS meeting and at the National Conference on Undergraduate Research (NCUR2003).
Tyler, shown here, is hanging out on the scaffolding assisting with maintenance on the ion source and buncher. Tyler graduated in May 2003 and entered the nuclear propulsion program.
JAMES TANYI ('01) battled broken equipment in the USNA Pelletron Accelerator Lab during Fall '99 and developed a great appreciation for the concept of buffering in a data acquisition system. After a bit of a struggle, he determined the elemental composition of a rock sample brought into the department from a member of the public in order to determine it's earthly/non-earthly origin. He used the combined techniques of PIXE and PIGE. The PIXE technique works best for elements between Z~13 and ~30. The PIGE technique provides access to the lighter nuclei, particularly Li, O, F, Na, Mg, and Al. The rock was ultimately found to be a coal cinder -- oh, well.
Over Winter Break '00, James traveled to the University of Kentucky Nuclear Structure Laboratory to participate in g-ray excitation function and angular measurements on 126Te using the (n,n' g) reaction. The analyzed these data for his year-long senior project. The Particle-Vibrational Core Coupling Model (PCM) model was applied along the tellurium isotopic chain, but 126Te was the first nucleus where it was clear the PCM was doing a good job with both the level scheme and transition rates. Tellurium-126 shows a clear deviation from the vibrational viewpoint applicable to the lighter nuclei.
James, shown here, is delirious after spending 2 days helping prepare the tritium cell for the experiment. His analysis of this data will establish much of the level scheme and spin structure of the 126Te nucleus. He presented the first portion of his results at the APS Nuclear Physics Meeting in Williamsburg, VA in October 2000. He reported on the remainder of his work at the National Conference of Undergraduate Research NCUR2001 in Lexington, KY in March 2001 and at the APS Spring Meeting in Washington, DC in April 2001.
James graduated in May 2001 and is attended graduate school in Radiological Sciences at the University of Michigan. James discovered Michigan is a lot colder than where he grew up and moved to the University of Texas at Houston where he is current finishing his Health Physics Training.
KEVIN CRANDELL (St. John's '00), worked for ~3 years on a variety of projects. He began in the USNA Pelletron laboratory in January 1999. He rekindled the isotopic abundance measurements started by LaBonte several years before. In particular, he concentrated on the Magnesium and Oxygen isotopes. The goal will be to reduce the uncertainties of the procedure from ~5% to <1%. Current targets of interest are Mg metal, MgO crystals, and the Murchison meteorite. He presented preliminary results at the Society of Physics Students meeting at Virginia Military Institute in April 1999.
During the summer of 1999, Kevin transferred over to work on other projects. He began the summer by learning to program in C++. Using these new-found skills, he wrote "replay" programs to examine the time dependence of gamma ray yield following beta-decay of 120I. The goal was to use the beta-decay rates to learn about the low spin states in the 120Te nucleus. As a result Kevin had the first firm evidence on intruder structures in the tellurium nuclei! Wow! These special intruder structures have been sought-after for over 10 years in the tellurium nuclei.
During his second year, he participated in one 126Te experimental run at the University of Kentucky and analyzed the gamma-gamma coincidence data from the 126Te experiment in conjunction with James Tanyi (above).
Following graduation, he received a Hodgson Fellowship grant from the Alumni Association of St. Johns College to develop a SNICS 7Li beam for users of the USNA’s 1.7 MV Pelletron in order to make simultaneous PIXE and RBS measurements of geological samples. .
He attended Pennsylvania State University as a graduate student in physics.
ROBERT COLEMAN ('99) traveled to the Paul Scherrer Institut in Villigen, Switzerland in order to produce the 120Te nucleus using 16-32 MeV alpha beams on a 118Sn target. This reaction actually produces a variety of residual nuclei which relax by emitting gamma rays. Excitation functions ( g yield vs beam energy) were measured to place the observed g-rays into their respective nuclei. Robert became one of the first people to observe the spin-structure of this nucleus up to ~4 MeV excitation. Spectroscopic results provided information on the behavior of nuclear vibrations in softly deformed potential wells and the interplay of particle and collective structures.
Tellurium-120 is a nucleus where because of the apparent simplicity of the level scheme, most models can satisfactorily reproduce the level sequence. On the other hand, agreement with the decay patterns between these levels is not impressive. Adequate lifetime information is still not available for this nucleus. Ratios of transition rates are most consistent with a simple anharmonic vibrator approach such as the U(5) limit of the IBM2.
ERIC JENSEN ('98) assisted with gamma-ray excitation function measurements on isotopically enriched 122Te at the University of Kentucky Nuclear Structure Laboratory during the summer of 1995. In addition contributing his part to the experiment in progress, he designed the initial web page for their laboratory. The current version may be viewed at http://www.pa.uky.edu/~marcus/nukes.html (Ok, it's been revised several times since 1995).
BRIAN CHAMPINE ('97) assisted with g-g coincidence measurements during the summer of 1995. He was intimately involved in assembling the target/shielding/detector arrangement, and cabling and debugging coincidence electronics for the three HpGe detectors. In addition contributing his part to the experiment in progress, he worked on an independent research project. Because of his previous programming background, he was given the duty of resurrecting program to calculate Coulomb excitation cross sections. As a senior, he has assumed responsibility for analyzing the natTe data. With his coincidence data and additional data on the lifetimes of state; he is examining how the two-particle and collective features of wavefunctions change as one moves through along the 126Te - 128Te - 130Te chain.
Brian traveled to the University of Texas, Austin to present the results of his work at the National Conference of Undergraduate Research in April 1997 and published a refereed paper in the conference proceedings.
He has completed Nuclear Power school.
MARK SKUBIS ('96) was involved in a variety of activities during the summer of 1995. Mark assisted with the g-g coincidence experiments on natCe and natTe. Mark had previous exposure to the creation-annihilation operator formalism from his quantum mechanics courses. Building upon this knowledge, he learned some of the basics concepts of the Interacting Boson Model and made calculations for the Tellurium nuclei. He also learned to program in FORTRAN and then assisted faculty members and an REU student with their computer-programming problems.
During his senior year he worked with Prof Engle making model calculations of the magnetopause of Saturn. He was awarded the United Daughters of Confederacy Prize for Physics Research upon graduation.
He graduated in May 1996 and the US Navy has allowed him to defer his commitment while attending MIT studying Nuclear Engineering. He attended Nuclear Power School and was been stationed on fast-attack submarines. He returned to the US Naval Academy as a physics instructor in ~2003.
In the photo at right, Mark appears to be in standing awe as the Univ Kentucky CN Van de Graaff's "Ion Sores" is serviced. You'd be in awe too if you got to do an experiment with the megariffic number of monoenergetic neutrons that this baby produces.
TIM MEEHAN ('95) has worked on various projects over three years. He came with strong math and computer skills and most of his activities have been related to data acquisition and reduction.
He first participated in the 142Ce measurements at the University of Kentucky during the summer of 1993. In addition to contributing his part to the experiment in progress, he worked on an independent research project. Gamma-ray spectra in experiments typically have 200-400 peaks. It is a great deal of work to pick out all the transitions by hand and retype them for peak stripping input. Often two or three gamma rays have nearly the same energy. Midn Meehan explored using signal processing and Fourier transform techniques to identify transitions. It was found that the critical parameter in identifying transitions is the full-width-half-maximum of the Gaussian peak shape function. Tim discovered that to approach the quality of identifications that can be done the by "hand and eye", one must utilize a FWHM that varies smoothly in the region under consideration.
Since the Spring 1994 semester, Midn Meehan has worked on developing multiparameter data acquisition programs using a Macintosh Quadra and the Kmaxª software. Kmaxª by Sparrow Inc., has the nice features that it uses the graphics and multiple-windowing capabilities of the Macintosh and doesn't require one to learn system service routines. His routines are used for a variety of applications from basic single detector measurements to specialized routines for PIXE measurements. Groups at Triangle University Nuclear Lab and the Naval Research Lab are watching our progress. The NRL is searching for a suitable replacement for their dated single parameter system.
After graduation, the Navy allowed him to remain at the Academy to continue his research. During summer 1995, he had sufficient experience to operate the UK accelerator by himself and to supervise beginning students.
Mr. Meehan has completed a Masters Degree in non-linear optics at Stanford University. Tim is shown here practicing his favorite pastime, jamming on the keyboards, -- computer keyboards that is....
BRIAN BENEDICT ('96) assisted in neutron scattering research on 142Ce at the University of Kentucky during the summer of 1993. In addition contributing his part to the experiment in progress, he worked on an independent research project. The final product of analysis of data is excitation energies, decay branchings, lifetimes, and spins and parities of excited states in the nucleus. The first three quantities are straight-forward to determine. The angular distribution techniques used to determine spins often lead to multiple solutions. Midn Benedict explored using a "Multi-dimensional Scaling" technique, commonly used in the social sciences, to gain additional information which could resolve ambiguities. This technique has been shown to occasionally work in lighter A = 26-60 nuclei by other groups. MDS techniques have never been attempted in the heavier nuclei A = 140. Brian graduated in 1996 and "jumped ship" to enter the Space Command branch of the US Air Force.
MATTHEW LABONTE examined several materials analysis techniques which could possibly be used to determine the isotopic composition of materials. Neutron activation, inelastic neutron scattering, and proton-induced reactions were considered. It was found that neutron activation was not sensitive to all isotopes of a given element, and that the count rates in neutron scattering were prohibitively low for small sample sizes. Proton-induced reactions appear promising for elements Z<30. After necessary modifications are implemented on the department's Pelletron particle accelerator, the work is expected to continued in the Spring of 1994.
He graduated in May 1993 and the US Navy has allowed him to defer his commitment while attending North Carolina State University / Triangle Universities Nuclear Lab studying Nuclear Physics. He completed his M.S., attended Nuclear Power School and is stationed on a fast-attack submarine.
JAMES SPAMAN assisted Tim Meehan in testing data acquisition systems during a portion of a semester. He has graduated and is an officer in the Marine Corps.
GERHARD SCHOENTHAL assisted in research at the University of Kentucky for two months during Summer 1991, during winter break, and during his senior year. He utilized the 127I(p,n) reaction to study the low-spin states of 127Xe. These levels are the final states populated following neutrino capture onto 127I in iodine-based solar neutrino detectors. He presented the results of his project at the APS Southeastern Section meeting and a paper was contributed to the Franklin Symposium in Celebration of the Neutrino. He was awarded the United Daughters of Confederacy Prize for Physics Research upon graduation.
He completed his commitment (SWO) and attending the University of Virginia, Charlottesville starting in Fall '97 to obtain a Ph.D. in Solid State Physics / Electrical Engineering - lithography. He now lives and works in Washington State, best I remember..
CHARLES McCARTNEY spent a semester studying the energy stability of NEC and HVEC accelerators using the LabVIEWª data acquisition package from National Instruments. Object-oriented programs were written to record control slit signals and to do online Fourier transform analysis. The results of his project were reported at an accelerator conference (SNEAP).
He graduated in May 1992 and the US Navy has allowed him to defer his commitment while attending Tufts University studying Electro-Optics. Upon completion of his M.S., he returned to the fleet.
PAUL LARSON worked at LANL/LANSCE for 4 weeks in the summer of 1990 assisting in the setup of parity violation experiments. Upon returning to the Academy during his senior year, he examined Acquired Polarization effects in parity-violation experiments. He presented the results of his project at the Washington APS meeting and a paper has been published in Zeitschrift fur Physik.
He graduated in May 1991 and the US Navy allowed him to defer his commitment while attending MIT in fusion research. He then joined the USN Nuclear Power community. He returned as an instructor in the Physics Department at USNA.