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.
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.
ERIC JENSEN ('98) assisted with gamma-ray excitation function mesaurements 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.
BRYAN HAAS participated in neutron scattering experiments at the
University of Kentucky to study vibrations of the spherical nucleus 142Ce
during the summer of 1992.
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.