Summer Research Projects, Department of Physics and Astronomy
Check back occasionally, as the list of projects might change. If you are interested in research opportunities, please click on the links below. We also encourage you to contact the individual department members associated with the projects for further information about the research.
Program Dates
May 30, 2023 - August 4, 2023Click on the project name for a more detailed description of the project
Project Name: Rare-isotope beam spectrometers
Project Mentor: Matt Amthor
Project Code: (MA-1)
Nuclear physics seeks to understand the structure of--and reactions between--nuclei, which are the dominant constituents (by mass) of the everyday stuff that we see around us. While the chemical properties are determined by the atomic number--determining which element a substance is--the nuclear properties change significantly across the different isotopes of a single element (atoms with more or fewer neutrons). Isotopes not typically found on earth--so-called rare isotopes, with atypically large or small numbers of neutrons for a given element--play important roles in the universe: energy generation in stars; production of the stable elements that make up our solar system; and the process of several kinds of explosive events, from supernovae to neutron star or black hole mergers.
We study rare isotopes experimentally by producing them in nuclear reactions in the laboratory, then examining how they decay or how they interact with other species in further nuclear reactions. Because rare isotopes are often short-lived, we often study them as particle beams, in-flight, immediately after they are produced, while still travelling at significant fractions of the speed of light. This project will focus on particle spectrometers, which are the tool that we use to separate and study the products that come from reactions with rare isotope particle beams. Your project this summer will be to examine and develop techniques to improve the operation of particle spectrometers by coupling computational models to Monte Carlo simulations and advanced optimization algorithms. The work may involve brief travel for experimental tests of these optimizations on actual particle beamlines, for example, at the Facility for Rare Isotope Beams (FRIB), a National Laboratory of the US Department of Energy that focuses on the study of rare isotopes, or at other facilities with similar research spectrometers.
Project Name: Theoretical and computational modeling of bacteria colony growth
Project Mentor: JiaJia Dong
Project Code: (JD-1)
In the forefront of population dynamics, the pioneering work by Lotka and Volterra in the 1920s sparked the interest in the class of predator-and-prey model in which the survival of each population depends directly on its interactions with the other. Motivated by the rich morphologic patterns found in bacteria colonies, we study a parasite-host type model by using a combination of theoretical and computational tools.
Through this project, you will have the opportunity to:
- study paradigmatic models in population dynamics;
- learn computer programming using Python, a general-purpose programming language widely used in research and industry;
- interact with research scientists and students;
- develop your own project;
- and many more challenging and exciting experiences as a physicist.
Project Name: Microscale mechanics of actomyosin networks
Project Mentor: Bekele Gurmessa
Project Code: (BJG-1)
Many intriguing phenomena are of fundamental scientific interest at a cellular scale. For example, several molecular interactions of cytoskeletal proteins can lead to large-scale collective motion of a cell. How can we integrate molecular-level knowledge to predict macroscopic assembly and structural re-organization in cytoskeletal proteins? One way is through exploring the mechanics, structural dynamics, and underlying physics of biological polymers of varying stiffnesses, compositions, and sizes at the molecular level. The cytoskeleton--a complex and dynamic network of biopolymers comprising actin, microtubules, and intermediate filaments--plays a vital role in several cellular processes ranging from the stability and rigidity of biological cells to cell motility and shape change. Central to this multifunctionality are the inherent stiffness of each filament and the myriad binding proteins that serve to crosslink, bundle, and stabilize these filaments. Exploring the mechanics and dynamics of in vitro reconstituted networks consisting of only one of these cytoskeletal components has been the subject of extensive experimental work. However, the role each cytoskeletal component plays in their composite networks' mechanical properties and structural dynamics is yet to be well understood. In this project, we couple optical trapping with advanced imaging to measure the nonlinear viscoelastic response and structural dynamics of in vitro reconstituted microtubules (MTs)--vimentin intermediate filaments (VIFs) composite networks by varying the relative concentration of MTs and VIFs. This project involves many hands-on experiments ranging from developing experimental protocols to creating \emph{in vitro} reconstituted composite networks and characterizing them via optical trapping and laser scanning confocal microscopy techniques. At the end of the summer, the student will develop skills in cutting-edge biophysical research (spectroscopy, advanced imaging, wet-lab handling, data acquisition, and analysis through Labview and Matlab, respectively), which are transferable to any future career (medical school, graduate school, etc.). Previous experiences in wet-lab, optical imaging, and programming in Matlab are desirable but not required.
Project Name: Locating and abolishing anti-Blackness in science curricula
Project Mentor: Deepak Iyer
Project Code: (DI-1)
Drawing on frameworks of abolition and critical race theory in education, in this student-faculty collaborative project, we will critically analyze science curricula for baked in anti-Blackness. We will use several lines of critical inquiry to trace the histories and modern day versions of anti-Black practices in science education, and how that leads to the vast disparities that we observe in outcomes. We will then look ahead to an alternative vision of science education that is actively devoid of this baggage, culminating in a practical plan to develop a curriculum for an introductory course in physics and/or related sciences that truly embraces a liberatory pedagogy. Please email d.iyer@bucknell.edu with questions!
Project Name: Chaotic mixing, swimming microbes, and propagating reaction fronts
Project Mentor: Tom Solomon
Project Code: (THS-1)
In a forest fire, the dividing line between burned and unburned trees is called a front. The motion of this front determines how the fire spreads through the forest. Similar front dynamics characterize the spreading of a disease in society, as well as numerous chemical processing applications, biological processes in cells and developing embryos, and plasmas in fusion reactors. We are currently conducting experiments that explore how the motion of fronts is affected by fluid mixing, e.g., forced flows in a chemical processor, winds in a forest fire, or the motion of people in society while a disease spreads. Table-top experiments using a simple chemical reaction (the well-known Belousov-Zhabotinsky reaction) focus on how fronts are affected by simple flow patterns -- vortices (whirlpools) and jets.
We are testing theories of "burning invariant manifolds" that predict barriers that stop the motion of reaction fronts in laminar (smooth) fluid flows. We have already done several experiments that have verified these predictions in two-dimensional flows, and we are currently extending these experiments to three-dimensional fluid flows.
We have also initiated studies of the motion of swimming bacteria in fluid flows. It turns out that the same theories that predict barriers for the motion of chemical fronts also predicts barriers in the motion of mutated "smooth-swimming" bacteria. We are doing experiments that study these barriers for bacteria swimming in microfluidic channel flows.
There is a lot of "hands-on" work involved in these projects, including the designing, building and testing of the experimental apparatus, mixing chemicals for the reaction, culturing of bacteria, and doing numerous experimental data runs. The experimental work also involves a substantial amount of computer-aided image analysis, almost exclusively on Linux workstations running a program called IDL. We also frequently conduct numerical simulations of the phenomena, also with IDL. Although experience in computer analysis is useful, it is not required as long as the student involved is willing and eager to learn IDL.
Project Name: Development of Atomic and Induction Coil Magnetometers
Project Mentor: Ibrahim Sulai
Project Code: (IS-1)
In my lab, we are interested in developing sensors to measure magnetic fields at the femto-Tesla level (i.e. 10−15 Tesla). For scale, the earth's magnetic field is over 10^8 times larger at 50 micro Tesla level. The motivation for making measurements of such small fields is to probe effects arising from physics beyond the standard model -- that is from particles that have been theoretically proposed to help explain some outstanding questions in physics such as "axions", and "dark photons". This summer, we will be working on two magnetometer designs: a cesium atomic magnetometer, and and induction coil magnetometer.
Atomic magnetometers work on the basis of the interaction of the atomic (cesium) spin and the background magnetic field. Using resonant laser light, we can read out the atoms interaction with the magnetic field. Cesium is attractive to us because of its low vapor pressure The goals of this project are to investigate ways of amplifying the signal using optical cavities. An induction coil magnetometer works on the basis of the Faraday effect, which states that a time varying magnetic field will induce a current in a coil.
Using low noise electronics, we plan to measure fields at the femto-Tesla level using both atomic magnetometers and the induction coil magnetometer. In addition to electronics, this project also involves work in optics, hardware development (machining, 3D printing etc), and signal analysis.
Project Name: Spectroscopy of Palladium Atoms and Ions
Project Mentor: Ibrahim Sulai
Project Code: (IS-2)
Palladium has six stable isotopes -- five of which have nuclear spin of zero. A consequence of this is that there is no nuclear magnetic interaction between the electrons and the nucleus and so the atomic structure of five of the six isotopes is significantly simplified. We are interested in determining the energy levels of some narrow transitions in the neutral and singly ionized palladium. The narrowness of the transition is related to the Heisenberg principle, as the excited states are long lived, and hence we call them metastable. We are able to determine the energy levels with high precision and this precision will allow us to search for (or constrain) subtle signatures of physics beyond the standard model that arise in interactions between neutrons and electrons. As a first step in performing this experiment, we will be developing a metastable atom source and observe the light that is emitted by the atoms using a spectrometer. A next step is to excite the atoms with an external light source -- looking at the absorption spectra. The work involves electronics, hardware design and optics.
Searching for Magnetic Interaction between Stars and Planets
Project Mentor: Jackie Villadsen
Project Code: (JV-1)
As the moon Io sweeps through Jupiter's magnetic field, it causes Jupiter to emit bright bursts of radio waves. Models predict that this should also happen when extrasolar planets orbit very close to their stars, causing the star to emit bursts of radio waves. If we can detect such radio bursts and measure their brightness, we can estimate the magnetic field strength of exoplanets, which is otherwise very hard to measure. Such radio bursts from such star-planet magnetic interaction have never been detected, but there are newly discovered exoplanet systems that make good targets. In this project, you will analyze radio telescope data for a nearby star with a close-in planet. You will use Fourier transform software to convert interferometer data to create an image of the sky, measuring the brightness of radio-emitting galaxies near the star in order to remove them from the data. Then you will use Python to graph the brightness over time of the star and look for any bursts that may recur with the planet's orbital period. This project does not require prior knowledge of Fourier transforms or python - you will learn on the job.
Computer Simulation of a Jammed Granular System
Project Mentor: Katharina Vollmayr-Lee
Project Code: (KVL-1)
Examples for granular materials are soap bubbles, rice grains, sand, and snow. They all have in common that the entities (e.g. bubbles) interact and energy is dissipated. At high density granular systems display fascinating phenomena such as avalanches and the jamming transition. In this project we study a system of disks which are packed in between to plates and sheared. In addition to the moving disks are not moving small disks, pins, representing obstacles. We study how these pins influence the jamming transition, the structure (spatial arrangement) and the dynamics of the moving disks. This project is part of a collaboration with the research group of Brian Utter at UC Merced, as well as the research groups of Amy Graves, and Cacey Bester at Swarthmore.
The student would work on implementing and running computer simulations using the public software package LAMMPS, as well as working on the analysis of the resulting simulations. No prior computer programming skills are required.