EXPERIMENTAL NUCLEAR PHYSICS
TITLE: Production and Study of Neutron-Rich Nuclei
(available for 2 students)
SUPERVISOR: Prof. Michael Thoennessen and Dr. Thomas Baumann
ABSTRACT:
During the last few years we constructed an experimental setup to measure very
neutron-rich
nuclei. It consists of a superconducting dipole magnet and subsequent charged
particle detectors
and the Modular Neutron Detector Array (MoNA) in order to measure neutrons in
coincidence with
the charged fragments. A collaboration between Michigan State University,
Florida State
University and 8 other colleges and universities are currently preparing for the
first experiments
which are scheduled for later in the summer. It is an ideal project for an REU
student to get
involved, because she/he will be involved in all of the final preparations,
including scintillation and
gas detectors, electronics, data acquisition and data analysis.
TITLE: Experiments with segmented Germanium Detectors for Nuclear
Structure
Studies
SUPERVISOR: Prof. Glasmacher
ABSTRACT:
We use liquid-nitrogen cooled high-purity Germanium detectors to detect photons
emitted from
nuclei in flight in order to study the structure of exotic nuclei far from
stability. The Segmented
Germanium Array (SeGA) is being set up for an experiment to be performed in
July. We invite a
student to participate in the preparation and execution of the experiment. More
information on
SeGA at groups.nscl.msu.edu/gamma/.
TITLE: Calibration of the S800 Spectrograph
SUPERVISOR: Prof. Alexandra Gade
ABSTRACT:
The focal-plane detector system of the NSCL's S800 magnetic spectrograph
contains two positionsensitive,
gas-filled particle detectors (cathode-readout drift chambers). In experiments
studying the
properties of exotic nuclei, the method to position-calibrate these detectors is
by inserting a mask
with a known pattern of holes and slits in front of the detector. The particles
coming through the
slits and holes mirror the pattern of the mask in the position spectrum of the
detectors. We invite a
student to participate in the analysis of this detector. The first part of the
project would be to
develop a computer code that identifies the pattern of the mask in the position
spectra of the
detector and relates the channel numbers in the spectrum to the actual physical
position given by
the known pattern of holes and slits in the mask and so calibrates the detector.
Furthermore, in
experiments it is very crucial that the response of this detector is
approximately constant over the
entire active area of the detector (roughly 30 x 60 cm). A movable alpha-source
will be installed to
measure the response at various positions. A second part of the project could be
to take data with
this calibration device and analyze the results.
TITLE: Angular Correlations in chiral, triaxial, odd-odd nucleus 134Pr
SUPERVISOR: Prof. Krzysztof Starosta
ABSTRACT:
For atomic nuclei triaxial deformation defines in the intrinsic, nucleus-fixed
reference frame three
mutually perpendicular directions along the principal axes of the mass
distribution and three
principal planes spanned by these axes. For valence nucleon in a particle or
hole orbital in a
triaxially deformed potential the alignment of the angular momenta with the
short or long axis is
favored, respectively; while the collective rotation of the nucleus aligns with
the intermediate axis
which is the axis of rotation preferred by a nuclear moment of inertia. In
specific configurations in
triaxial odd-odd nuclei the three mutually perpendicular angular momenta
provided by a valence
particle, valence hole and collective rotation are mutually perpendicular and
can be arranged into a
right-handed or a left-handed system.
As a consequence of the two possible couplings, doublet states of the same
spin/parity and nearly
identical excitation energy are formed for a given single particle
configuration. Indeed, doublet
band structures have been observed systematically in the triaxial A~130 and
A~105 regions. The
best examples of level degeneracy in the mass A~130 region is provided by 134Pr
with levels at
spin 15+ and 16+ separated by less than 60 keV as compared to ~8000 keV spanned
by the bands.
For the 134Pr high quality and high statistics gamma-ray spectroscopic data are
available from a
Gammasphere experiment. The Gammasphere is a multi-detector system for gamma-ray
studies;
with 110 detectors packed around the target it looks like a big sphere of
gamma-ray sensitive Ge
crystals (you may have seen the detector in a recent movie "Hulk", in the movie
Hulk actually has
dropped the Gammasphere detector down from a hill in Berkeley, in reality,
however, the detector
is still up and running).
From the Gammasphere experiment on 134Pr the nuclear structure information can
be extracted by
investigating angular correlations between gamma-ray transitions. These
correlations arise due to
the preference of gamma rays to be emitted in particular directions during the
decay of excited
states in the nucleus of interest. The analysis of these correlations is a
crucial step in establishing
spins and parities for nuclear states, and consequently, for experimental proof
of the doubling of
states with the same spin and parity.
The scope of the current project is to extract the information on angular
correlations of gamma-ray
transitions in 134Pr from the available Gammasphere data set. The project
involves state-of-the art
computer manipulation of large data basis. In the process of extracting the
relevant information you
will have an opportunity to learn the physics underlying nuclear structure of
deformed nuclei and
physics of gamma-ray angular correlations. You will also apply, modify and
develop software tools
for the analysis of the experimental data. The project requires familiarity with
basic concepts in
computer programming. The analysis, which is the goal of the current project, is
the necessary step
in manuscript preparation for a paper on 134Pr from the Gammasphere experiment;
by getting
involved in this project you will become a part of the collaboration and when
the project is
successfully completed, a co-author of the paper.
TITLE: Lifetimes of nuclear states via time-of-flight method
SUPERVISOR: Krzysztof Starosta
ABSTRACT:
The goal of the current project is to develop a time-of-flight technique for
lifetime measurements
with fast beams of radioactive nuclei from nuclear fragmentation reaction. The
idea behind this
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method of lifetime measurements follows the Recoil Distance Method (RDM or
plunger)
technique, which has a long tradition of use at stable beam facilities, however,
a number of
modifications is needed for optimal application of the method at National
Superconducting
Cyclotron Laboratory (NSCL).
In the approved NSCL test experiment a beam of the Pd isotopes of interest with
a velocity
beta=v/c=0.33 and an energy of ~54 MeV/u will be directed on a 50 mg/cm^2 93Nb
target and
excited to the first excited 2+ state. Nuclei of interest will emerge from the
target with velocity
beta'~0.30 and decay in flight after a certain distance; the distance which
corresponds to the halflife
is on the order of a few millimeters. A movable 9Be reset foil with 80 mg/cm^2
thickness,
positioned downstream with respect to the 93Nb target, will be used to reduce
the velocity of the
beam to beta"~0.26. As a consequence, the gamma-ray from the 2+ excited state
will be emitted at
different source velocity if the decay occurs before or after the reset foil.
The velocity of the source
affects the Doppler shift for the gamma ray, which can be detected
experimentally, allowing
identification of decays that took place in front or behind the reset foil. The
ratio of these decays
provides an information about the lifetime if the distance D between the 93Nb
and 9Be foils and
the beam velocity beta' is known.
A "plunger" device, which allows controlling the distance D between the target
and the reset foil
with accuracy on the order of micrometers, is currently being designed and
manufactured at the
NSCL for applications in the above lifetime measurements. The goal of the
current project is to
contribute to the development of the method by tests and calibrations of the
plunger device, as well
as by modeling optimal experimental conditions with application of computer
codes.
TITLE: Characterization of a Position-Sensitive Neutron Detector for Use
in Nuclear
Equation of State Experiments
SUPERVISOR: Dr. Michael Famiano and Prof. William Lynch
ABSTRACT:
Neutron detector walls consisting of two stacked arrays of liquid scintillators
were used in
experiments to study the asymmetry term in the nuclear equation-of-state (EOS).
It is necessary to
know the energy dependent efficiency of these walls for an effective analysis.
Measurements can
also be affected by scattering outside and inside the detector. A simulation of
these neutron walls
will enable a better understanding of some the effects on measurements. This
project involves
assisting with the writing of a simulation using GEANT4.4.0 and analysis of the
results of the
simulation. Experience with C++ is necessary for this project.
TITLE: Testing and development for the LEBIT project
(available for 2 students)
SUPERVISORS: Prof. Georg Bollen and Dr. Stefan Schwarz
ABSTRACT:
The Low-Energy Beam and Ion Trap Project aims at high precision experiments on
unstable
isotopes available at the NSCL. In this project high-energy beams of rare
isotope are converted into
low-energy beams by using gas-stopping and ion trap techniques. The first type
of experiments will
be high-precision mass measurements of unstable isotopes. Such measurements are
important since
they provide information on the binding energy of a nucleus, which is one of its
most fundamental
properties. At LEBIT such measurements will be carried out with a Penning trap
mass
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spectrometer, which allows mass measurements of atoms with a relative precision
better than 1 part
in 10 million. Other important components of LEBIT are a high voltage ion beam
transport system
with a test-beam ion source and a radio frequency ion trap for beam cooling and
bunching.
The installation of LEBIT is practically completed and the project is entering
the important phase
of testing and optimization, required prior to experiments with rare isotopes.
Examples of possible
REU projects are:
• Systematic study and optimization of ion beam transport parameters and
comparison with
ion optical calculations.
• Development and test of electronic components for the Penning trap and other
LEBIT
subsystems.
• Monte-Carlo simulations in ion traps.
In addition, students will participate in test-experiments of the whole LEBIT
system, which are
foreseen to take place this summer, and help in the installation of new
components.
THEORETICAL NUCLEAR PHYSICS
TITLE: Nuclear Femtoscopy for High-Energy Collisions
SUPERVISOR: Prof. Scott Pratt
ABSTRACT:
The RHIC (Relativistic Heavy Ion Collider) at Brookhaven creates the world's
ottest laboratory
environment with temperatures surpassing 200 MeV. Within the esoscopic collision
volume
(~1.0E-14 m, the size of a gold nucleus) the ormal structure of the vacuum is
expected to melt and
a transition to uark-gluon degrees of freedom should take place. Unfortunately,
the novel onditions
only last ~1.0E-22 seconds and experiments are relegated to easuring the momenta
of the ~5000
particles comprising the collision debris. pace-time information about the
collision can only be
gathered from wo-particle correlations. By performing numerical modeling of the
collision nd some
analytic calculations of correlators, we will try to improve on stimates of the
collision lifetime
which are crucial for understanding the quation of state of the matter. Most of
the work is
numerical, but the omputing techniques can be learned during the first few weeks
of the program.
please don't hesitate to email me (pratts@pa.msu.edu) or call me (517-355-9200
2016) if you wish
to discuss the project further.
TITLE: Radiance and nuclear giant resonances
SUPERVISOR: Profs. Vladimir Zelevinsky and Alex Brown
ABSTRACT:
The phenomenon of super-radiance is known in quantum optics. If the system of
many two-level
atoms is placed into a volume of a size smaller than the wavelength of radiation
between the two
levels, the atoms are coherently coupled through their common radiation field.
When the pulse of
radiation travels through the system a special state of the excited atoms can be
formed that radiates
very fast while the remaining ("trapped") states turn out to be very long-lived.
There are analogs of
this phenomenon in nuclear physics and condensed matter physics.
The proposal is to study the superradiant and trapped states in simple models.
In particular it is
interesting to relate recently observed so-called "pigmy"-resonances in loosely
bound nuclei to the
physics of superradiance. This part of the giant resonance is getting clearly
pronounced when the
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nucleus is far from the stability line and therefore strongly coupled to the
decay channels. This
points out to the possible link to the super-radiance phenomena. The solid-state
models of periodic
structures with open ends can also be studied from the same viewpoint.
Basic acquaintance with quantum mechanics is desirable. The work should be
mostly analytical
with simple computations in the end.
TITLE: Symmetry Energy in Nuclear Reactions
SUPERVISOR: Pawel Danielewicz
ABSTRACT:
In nuclear reactions, the matter that nuclei consist of gets compressed. From
the fact that nearly all
nuclei have about the same, so-called normal, density in their interior, we
conclude that the nuclear
energy minimizes, as a function of density, at the normal density. Beyond the
minimum, the
nuclear energy as a function of density is a subject of intense scrutiny.
Knowing about the energy,
we could make predictions on neutron stars which, collapsed under gravity, have
density many
times greater in their interior than nuclei. However, the nuclear energy depends
not only on
density, but also on the percentage difference in the neutron-proton composition
of nuclear matter.
Light nuclei are most often composed of 50% neutrons and 50% protons, in heavy
nuclei the
composition is typically 60%-40%, and, in neutron stars, the neutrons dominate.
The coefficient
describing the dependence of nuclear energy on composition is called symmmetry
energy. The
symmetry energy needs to be understood to make extrapolations to neutron stars.
In theoretical transport simulations of nuclear reactions, the adopted symmetry
energy has often
been of a highly simplified form, limiting the insights that could be gained
from comparing
simulation results to data from reactions with varying neutron-proton
composition. The project
consists in implementing and exploring a variety of symmetry energy forms within
existing
transport simulations, potentially testing the forms against data. A rainy-day
part of the project
would include migration of simulation outcomes and their analysis to Unix.
TITLE: Testing Excitation with a Simple Adiabatic Model
SUPERVISORS: Prof. Filomena Nunes and Dr. Neil Summers
ABSTRACT:
Light exotic nuclei are mainly probed through reactions with stable targets.
Although most of the
reaction models developed so far assume that the constituents of the exotic
nucleus remain inert
throughout the reaction process, there are indications that this assumption may
not be valid. We
propose to include excitation in a simple adiabatic reaction model to probe the
importance of this
effect. The project will involve an analytical evaluation of the problem
followed by numerical
computation of the resulting integrals.
ASTROPHYSICS and NUCLEAR ASTROPHYSICS
TITLE: Variable Stars in Globular Clusters and the Galactic Halo
SUPERVISOR: Horace Smith
ABSTRACT:
Pulsating variable stars change in brightness because of periodic changes in
their diameters and
surface temperatures. RR Lyrae stars and type II Cepheids are keys to
determining distances to old
6
stellar populations and test cases for understanding the evolution of lower mass
stars. Because they
are very old, they also provide information on the processes by which the Galaxy
formed. We will
analyze the properties of RR Lyrae stars and type II Cepheids using (i)
observations obtained with
the 60-cm reflecting telescope on the MSU campus and (ii) observations obtained
during the
ROTSE-I project at Los Alamos National Laboratory. Part of this project will
involve getting new
observations of these stars and part will be based upon observations already in
hand.
TITLE: Globular Clusters and Low-Mass X-ray Binaries
SUPERVISOR: Prof. Stephen Zepf
ABSTRACT:
Globular clusters are one of the few places in the universe where the density of
stars is high enough
that they interact closely. One of the results of these gravitational
interactions is the formation of
very close binary star systems in material from a normal star is pulled onto a
companion neutron
star or black hole. This heats up the infalling material so that it radiates at
X-ray wavelengths.
There are a handful of such systems known in the Milky Way, but the combination
of Hubble
Space Telescope imaging of globular clusters and X-ray imaging from the Chandra
Telescope
allow the study of this process in much larger numbers in nearby galaxies. The
project will be to
combine Hubble and Chandra data to learn more about how these low-mass X-ray
binary systems
form and evolve.
TITLE: Southern Astrophysical Research (SOAR) Telescope
SUPERVISOR: Prof. Jack Baldwin
ABSTRACT:
The SOAR telescope was just dedicated, and will begin observations this summer.
The astronomy group will have LOTS of work over the next year involving SOAR. We
can use computer-adept undergraduate students in several ways during that time:
• occasionally observing remotely on SOAR for engineering tests and/or
scientific programs.
• helping to analyze engineering data.
• helping to write/test remote observing software.
• creating web sites.
We are looking for undergrads who already have the computer background so
that they could jump very quickly into actually being helpful at these
tasks. Either Linux or Windows knowledge would be of interest.
This project could take two students for the summer.
TITLE: Reaction Networks for Thermonuclear (type Ia) Supernovae
SUPERVISOR: Prof. Edward Brown
ABSTRACT:
Hydrodynamical simulations of thermonuclear (type Ia) supernovae require as
input the energy
release from nuclear reactions, the rate of electron captures and the rate of
neutrino emission.
These quantities are computed using a network of equations to describe the
nuclear burning. It is
not feasible to include all relevant isotopes, however, and so these codes must
employ an
approximate set of equations that reproduces the burning rate and tracks the
evolution of the mean
nuclear mass and electron to nucleon ratio. In this project, the REU student
will design, test and
implement a network for use in simulations of type Ia supernovae. Recent studies
suggest that the
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concentration of Ne22 in the white dwarf plays an important role in setting the
peak brightness of
the supernova, and the network must account for this. The student will learn how
to analyze the
reaction network, and about stellar explosions in general. During this project,
the student will
interact with members of the nuclear astrophysics research group at the Joint
Institute for Nuclear
Astrophysics at the National Superconducting Cyclotron Laboratory. Knowledge of
programming
is useful.
TITLE: Nuclear reaction rates in stellar explosions
SUPERVISOR: Prof. Hendrik Schatz
ABSTRACT
Explosions on the surface of neutron stars are powered by nuclear reactions and
are frequently
observed as bright X-ray outbursts. In fact, these outbursts occuring on an
hourly basis in many
sources are among the brightest objects in the sky. However, as X-rays do not
penetrate the
atmosphere, they can only be observed by X-ray telescopes in orbit.
Recently, a number of theoretical and experimental results have allowed to
determine the nuclear
reaction rates in X-ray bursts much more reliable. The project consists of
extracting the relevant
data from publications and bringing them into a form that can be used in X-ray
burst models. This
invloves some basic mathematics and curve fitting. The results are then plugged
into an X-ray burst
model to see, whether the predicted light curve of the explosion changes due to
the new data. Some
basic experience with computer programming would be helpful for this project.
CONDENSED MATTER PHYSICS
TITLE: Giant Magnetoresistance in Magnetic Multilayers (experimental)
SUPERVISORS: Profs. Jack Bass and William Pratt
ABSTRACT:
Giant Magnetoresistance (GMR) in Magnetic Multilayers is of interest both for
the
underlying physics and for technology--the read heads in modern computer hard
drives
are now GMR multilayers. The MSU group pioneered measurements of Giant
Magnetoresistance in Metallic Magnetic Multilayers with Current Flow
Perpendicular to
the Layer Planes, a geometry that usually gives more direct access to the
physics
underlying GMR. A specific project will be chosen after discussion with the REU
student. The project will involve sample preparation (using a state-of-the-art
sputtering
system), sample characterization, and measurement of magnetoresistance. The
project
might also involve optical and electron-beam lithography in collaboration with a
Ph.D.
student or Postdoc.
TITLE: Development of an image-plate x-ray camera for studying of the
structure
nano-materials
SUPERVISOR: Prof. Simon Billinge
ABSTRACT:
Nanoscience and nanotechnology are two current "buzz-words" in physics that
refer to the
development of materials that take advantage of special properties associated
with their small size,
where small here refers to the nanometer length-scale. A major stumbling block
in this endeavor is
to study the atomic-scale structure of materials of this dimension since
conventional approaches to
8
structure solution fail for these materials. In my group we are developing novel
methods using
advanced x-ray and neutron scattering to do this. The REU project will be to
develop and
commission an x-ray camera for collecting data using recent image-plate
technology. The camera
has been designed and built by us, but has to be configured and tested and then
data from the
camera have to be extracted and analyzed. The project will be a mixture of
hands-on work to
configure and commission the camera, experimental work in the form of data
collection, and
computer analysis, including some code writing, to extract and process the data.
No specific
experience is needed except some experimental aptitude and interest and basic
confidence in using
computers. Some straightforward programming skills will also get you going more
quickly with
that aspect of the project.
TITLE: Quantum Cryptography and Entanglement
SUPERVISOR: Prof. Carlo Piermarocchi
ABSTRACT:
On 21 April 2004 an Austrian scientist has used for the first time a quantum
cryptography protocol
in a $3500 bank transaction (see Nature Apr. 29 2004 p 883). The protocol is
based on sharing a
pair of entangled photons to create the encoding key. Upon arrival, both photons
are measured by
their respective owners. This act of measurement determines the state of the
photons, and thus the
state of the key. One important issue for the success of quantum cryptography is
related to the
availability of efficient devices to generate entangled pairs. Quantum dots are
man-made
semiconductor nanostructures that are very promising in this direction. The
project consists of two
parts: (i) introduction to quantum cryptography protocols, in particular the
ones based on sharing
EPR pairs. (ii) Investigation of semiconductor quantum dots as a source of
entangled photons and
single photon emitters.
BIOLOGICAL PHYSICS
TITLE: Projects in Molecular Biophysics
(available for up to 3 students)
SUPERVISOR: Prof. William Wedemeyer
ABSTRACT:
First Project. In this REU project, we seek to develop fast techniques for
detecting when biological
molecules stick together. We will exploit the basic principle that the random
tumbling of
molecules in solution becomes slower when the moment of inertia is increased. We
will measure
the tumbling rate principally by dielectric dispersion, but will cross-check our
results using
fluorescence depolarization and non-Newtonian viscosity measurements.
Applications include
rapid detection of bacterial/viral DNA and the discovery of novel
pharmaceuticals.
Second Project. In this REU project, we will seek to develop new techniques for
measuring the
structure of biological molecules from X-ray solution scattering. Specifically,
we will measure the
difference in X-ray scattering from a protein and from a homolog in which a
single chemical group
has been eliminated. The difference spectrum should give the distribution of
distances between the
eliminated group to all other atoms in the protein. By repeating such
experiments with different
eliminated groups, a low-resolution picture of the entire protein should be
obtainable. The proteins
have been prepared; the student need only take the X-ray spectra and interpret
the results.
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Third Project. In this REU project, we will study the energies of interaction
between rigid protein
molecules and the surrounding solvent. We will carry out a systematic study of
the solubility, heats
of solution, molecular volume, orientational correlation time and dipole moment
of twenty proteins
that differ in a single position. The experimental data will be compared to
computational
simulations and used to make improved energy functions for proteins. The
proteins have been
prepared; the student will carry out the measurements and interpret the results.
HIGH-ENERGY PHYSICS
TITLE: Parton Distribution Functions
SUPERVISOR: Profs. Wu-Ki Tung and Dan Stump
ABSTRACT:
The Parton Model describes the quark structure of the nucleons (protons and
neutrons).
One project would be to study different models and their agreement with data
from highenergy
scattering experiments. Another model would be to study predictions of future
experiments based on current parton model parameters, and the uncertainties of
the
predictions. One definite project is to study and compare examples from the new
LHAP
compendium of parton distribution models.
PHYSICS EDUCATION
TITLE: LON-CAPA Platform Development
SUPERVISOR: Profs. Gerd Kortemeyer, Ed Kashy and Wolfgang Bauer
ABSTRACT:
LON-CAPA is an award-winning program for teaching physics and other subjects.
The LONCAPA
development team offers two projects to REU students for this summer.
Platform Development: This project will require solid existing programming
experience,
preferably in Perl and in the development of web applications. The students will
be members of the
LON-CAPA development team over the summer, and work to implement new
functionality within
the LON-CAPA system.
TITLE: LON-CAPA Physics Problems Development
SUPERVISOR: Profs. Gerd Kortemeyer, Ed Kashy and Wolfgang Bauer
ABSTRACT:
LON-CAPA is an award-winning program for teaching physics and other subjects.
The LONCAPA
development team offers two projects to REU students for this summer.
Physics Problem Development: In this project, students will work with faculty in
the LON-CAPA
project to development new homework problems for introductory physics with a
focus on real
world conceptual problems.
ACOUSTICS
TITLE: (may be available if a student is especially interested in this
field)
SUPERVISOR: Prof. William Hartmann