Members of our senior class investigated an impressive range of research topics in the past year.
Syndi Bond ’18
Advisor: Tom Balonek
Variable Stars and Their Light Curves in the BL Lacertae Star Field
Prior projects and work on the BL Lacertae star field, most of it intended to collect data on the quasar, helped result in decades worth of collected data on the stars in the surrounding star field. This research builds upon that collected data in a natural way by analysis of the light curves of 5 neighboring stars through the images and data gathered from the summers of 2012 and 2014. Variable stars require many years of data collection and processing to simply go from observation to discovery of which stars are indeed variable. The images and data in this project were obtained from data archives and notebooks that are taken care of at Colgate University’s Foggy Bottom Observatory. These same images were analyzed and processed using two software programs: ImageJ and Kaleidagraph. As a result, of the 5 stars analyzed, 2 were found to be comparison stars with minimal to no variability and 3 were found to be quite variable over the course of the summers.
Christina Bowers ’18
Advisor: Ken Segall
Exploring Fluxon Tunneling in a Parallel Josephson Junction Array
Josephson Junctions are superconducting circuit elements with characteristics that are useful for studying nonlinear systems and notably are a strong candidate for use in quantum computing. We seek to find concrete evidence confirming the observation of Macroscopic Quantum Tunneling (MQT) of fluxons in Josephson Junction rings. During my research, we refined the methods used for testing the arrays to decrease error due to flux trapped in the wires of our apparatus. Additionally, we designed a procedure to sweep through magnetic field values to determine the best field for trapping a fluxon. We found a promising value and plan to further analyze the switching current data with the hope of verifying fluxon travel via MQT through the Josephson Ring with quantitatively rigorous and reproducibleresults.
Logan (Cooper) Conran ’18
Advisor: Kiko Galvez
Ghost Imaging
Ghost imaging is a technique where an object is imaged by light that never interacts with it. The technique utilizes the temporal and spatial correlation between entangled photons. The entangled photons are created through spontaneous parametric downconversion, in which the signal beam is directed toward the object to be imaged, while the idler beam is directed towards an imaging device, such as a time-gated camera or scanning single-pixel detector. Our work focuses on getting basic ghost imaging with hopes of applying it to medical imaging such as deep imaging of tissue.
Sean Corrigan ’18
Advisor: Jonathan Levine
New Data Analysis Techniques for an In Situ Spaceflight Dating Mass Spectrometer
The goal of this project is to improve data analysis techniques for the prototype resonance ionization dating mass spectrometer currently being developed by my advisor Jonathan Levine and collaborators F. Scott Anderson and Tom Whitaker. Dating a geologic sample by this method involves laser ablation of the sample surface. Fluctuations in laser power can have significant effects on the data produced by the mass spectrometer. With this project we develop new data analysis methods to correct for the effects of fluctuating laser power.
Brendan Corrodi ’18
Advisor: Rebecca Metzler
Dependence of Coral Structure and Hardness on Environment in Common Florida Coral Species
Coral is a vital part of our modern world. The ability for coral to continue to live is important both for continued research and for the safety and prosperity of our current coastlines. My research looks into how changing water conditions affect the structure of coral samples from the Florida coast by comparing a fossilized sample and a modern sample from the same genus of coral. The goal of my research is to determine how coral will deal with continued climate change and rising sea temperatures, hopefully showing an ability to adapt despite the rapid change. After taking data from three different sources on Porites coral samples, there seems to be a trend towards a denser coral structure from the Pliocene era coral to coral today.
Anthony D’Addario ’18
Advisor: Ken Segall
Computational Model of Neural Synapse Characteristics Using Josephson Junctions
We seek to develop an understanding of the behavior of large neuron systems using superconducting circuits containing Josephson junctions. This paper begins with a review of previous studies that have shown Josephson junction neurons acting as biologically realistic models for neurons. The JJ neuron has reproduced mechanisms similar to action potentials, refractory periods, firing thresholds, as well as other characteristic properties of neurons. A review of the JJ axon is also included, followed by a discussion of a proposed three-step Josephson junction method to model the complicated behavior of neural synapses. The JJ synapse model will include a Learning Gate that compares the time between two neuron pulses, a Memory Cell that stores flux proportional to the output of the Learning Gate, and a Variable Attenuator that varies the synaptic weight between two neurons. Previous work has shown a working model for the Learning Gate and this paper discusses the Memory Cell and attempts to combine both circuits into one.
Michael DiGiorgio ’18
Advisor: Rebecca Metzler
Comparing Compositional Structures of Sea Urchin Spines
Sea urchin spines are single crystals of calcium carbonate which are formed after the urchins stabilize amorphous calcium carbonate, or ACC. This stabilization process, as well as the way in which the urchins shape the crystals, are both subjects of extensive research. We compare the compositional structures and make-up of two species of sea urchins using SEM imaging, infrared spectroscopy, and microindenting, so as to better understand any similarities or differences in how different urchins seem to form their spines.
Julia Dottinger ’18
Advisor: Patrick Crotty
Effects of Neurodegeneration on the Memory Capacity of the Hippocampal CA3 Region
In this study, we modeled the CA3 region of the hippocampus and considered the effects that neurodegenerative diseases could have on the dynamics of this neural network. We generated neural networks of different sizes and determined their memory capacity under healthy conditions as well as removed synapses from these networks to determine the decline in memory capacity that would result from synapse or neuron death. By modeling neurodegenerative diseases that affect the network topology and function of the hippocampus, we can further our knowledge of how the hippocampal neural network performs its computational processes under both healthy and diseased conditions.
Muriel Drexler ’18
Advisor: Jonathan Levine
Understanding, Quantifying, and Demonstrating the Conservation of Energy
The goal of this project is to develop demonstrations that show the conversion of energy into different forms in order to be able to quantify the energy that is transformed in different systems and prove that energy is conserved through all forms in all systems. The system used and discussed is a simple device consisting of a thermally insulated tube filled with a mass of buckshot; gravitational potential energy of the buckshot is transformed into heat by turning the tube over repeatedly; each turn lifts the buckshot by the tube length, then allows it to fall the same distance, with the resulting kinetic energy turned to heat when the buckshot pellets crash into one another at the base of the tube. Methods of refining the experiment will be discussed, including altering certain variables including the tube length, the mass of the buckshot, and the rate of turning the tube in order to obtain a better understanding of the energy coming into and out of the system and be able to quantify its relationships with the aforementioned variables. Finally the results are discussed, wherein an accurate mean value of the specific heat of the buckshot was obtained but with a wide spread of individual values, and the discrepancy between the model and the data was greater than the estimated uncertainty of measurements, calling for a more precise data collection process as well as a possible reworking of the latest model.
Megan Emch ’18
Advisor: Jeff Bary
Spectral Analysis of Accretion and Outflow Activity on DQ Tau
The tight eccentric binary star system DQ Tau is an ideal model for the investigation of the development of accreting star systems, which may eventually become planetary systems. The period of DQ Tau (P=15.8043± 0.0024 days) allows for the collection of large amounts of data within a short time span. Since over 50% of stars exist in binary and higher order star systems, it is imperative that we assess the likelihood of planetary formation in systems like DQ Tau so that we can further the search for life in the universe. I therefore present high resolution spectroscopic analysis of optical and near-infrared spectra (3,200-10,000 Angstroms), which indicate the sources and radial velocities of accretion and mass outflow activity occurring in DQ Tau. I discuss H-alpha (6563 Angstroms), [O I] (6300 Angstroms), Ca II triplet (8498, 8542, and 8662 Angstroms), and Na doublet (5890 and 5896 Angstroms) emission and absorption features.
Zachary Frohock ’18
Advisor: Jonathan Levine
Computational Model of Rubidium and Strontium Resonance Ionization
I have created a model of the resonance ionization process of rubidium and strontium when exposed to light produced by a fiber optic laser. I use this model to analyze the feasibility of these lasers for use in a spaceflight dating mass spectrometer, focusing on ensuring that the ionization rate is resistant to normal operating parameter variations. From this, it seems we can conclude that the lasers are well suited for such an operation.
Kelly Haberl ’18
Advisor: Jonathan Levine
Analyzing Properties of Lead for the Development of a Spaceflight Dating Mass Spectrometer
Dating rocks on the surface of Mars presents a unique challenge because common radioisotopic dating techniques are impractical for spaceflight due to size, mass, or power constraints. An ongoing project run by Professor Levine and a team at the Southwest Research Institute in Colorado has built a prototype mass spectrometer, suitable for spaceflight, that measures isotopic abundances of radioactive 87Rb and its daughter 87Sr, so that a sample’s age can be determined. The isotopic analysis is made by resonance ionization mass spectrometry, in which tuned lasers separate these elements by optically exciting and ionizing atoms of each element, with the ions then passing through a time-of-flight mass spectrometer to separate them by mass. My research explores using abundances of lead isotopes, rather than Rb and Sr isotopes, for dating with the same mass spectrometer. In theory, lead isotopes allow sample ages to be determined with fewer measurements and fewer lasers than the analysis of Rb and Sr. However, as the tuned lasers progressively excite lead atoms to higher energy states, the atoms pass through a state at 51944 cm-1 for which two important atomic properties have never before been measured. These are the Einstein A coefficient for the transition between this state and a lower one at 35287 cm-1, and the photoionization cross section from this state. By creating a computational model of lead atoms interacting with lasers of varying frequency, I show how the ionization yields we observe can be used to constrain these two physical quantities.
Katherine Kelleher ’18
Advisor: Patrick Crotty
Dynamics of Hippocampal Place Cell Models with Biologically Realistic Neurons
Place cells are a type of place-selective neuron located in the CA3 region of the hippocampus. The connection between neurons forms a neural network, the structure of which is referred to as network topology. The topology of this hippocampal region is largely unknown, however the region as well as the place cells are associated with spatial navigation. The dependence of memory capacity on network topology is shown by perturbing the network and measuring the resulting number of charts that can be stored in the network. The models previously used to display the reliance of spatial chart capacity on topology are based off of simple, biologically-inaccurate assumptions. In this research we shift our code to a new simulator tool, NEST, to allow for the inclusion of biologically accurate parameters to better model the CA3 region. In future research this will be used to study the change in behavior of the place cell model under more realistic constraints.
Linh Le ’18
Advisor: Linda Tseng
Pharmaceuticals and Personal Care Products (PPCPs) in Treated Water in Hamilton, NY
The presence of pharmaceuticals and personal care products (PPCPs) in natural water sources is a growing concern, particularly because of the harmful effects of these contaminants on the environment and human health. Gas chromatography-mass spectrometry (GC/MS) is a useful technique to detect these compounds. The method was used to quantify the concentrations of diclofenac, atenolol, ibuprofen, 4- cetamidophenol and bisphenol A in water before and after treatment in Hamilton, NY. Results indicate that biological treatment during the secondary treatment stage effectively removes large amounts of contaminants except for 4-acetamidophenol, while farming adds diclofenac, atenolol and bisphenol A to the effluent after treatment. 4-acetamidophenol is not affected by the treatment or human activity. These results offer a closer look at the effectiveness of the treatment facilities in Hamilton and their impact on the environment.
Laura Leonard ’19
Advisor: Linda Tseng
Plasticizer Leaching and Chemical Presence in Poland Spring and Smart Water Bottles
The bottled water industry is known for its image of purity; however, bottling companies are not held to the same treatment standards as tap and municipal water. Additionally, the plastic bottles water comes in are also a public health risk. Plastic bottles can contain plasticizers which are long carbon chains that help make plastic more flexible and versatile. These plasticizers are frequently known to be carcinogens and endocrine disruptors. Upon examining the water from Smart Water and Poland Spring bottles exposed to different conditions, five major chemicals: diclofenac, atenolol, ibuprofen, 4-acetamidophenol, and bisphenol-A, were observed to be present within the samples.
Romario Lobban ’18
Advisor: Ken Segall
Investigating the Dynamics of Systems of Coupled Josephson Junctions
We examine a system of coupled oscillating Josephson Junctions (both experimentally and through simulations) to better understand the order in which the junctions’ oscillating frequencies fall out of synchronization with each other. Correcting for inconsistencies between experimental and simulated data, we discover unexpected effects of temperature as well as of the chip fabrication process.
Stephen Paolini ’18
Advisor: Ken Segall
The Nonlinear Dynamics of Vortex-Breather Collisions
Breathers and vortices are two solutions to the equations that govern the coupled nonlinear dynamics describing Josephson junctions in a ladder array. These solutions have yet to be observed interacting through collision resulting in a pinning event. In simulating such collisions, we hope to better understand the dynamics Josephson junctions and consequently their potential applications. Furthermore, these simulations will yield theoretical data which we can then compare to experimental data. Thus, we can better determine whether pinning events have been observed and further our understanding of nonlinear dynamics.
Henry Parker ’18
Advisor: Walter Tangarife Garcia
Forbidden Dark Matter
Forbidden dark matter is a novel dark matter candidate, with a range of masses from the keV to weak scales, that annihilates into heavier states in the early universe. These forbidden channels turn off at late times when the mass of these heavy states exceeds the temperature of the universe, naturally evading constraints from the cosmic microwave background. I analyze past work on the paradigm with a primary focus on the work of D’Angelo and Ruderman (2015) by supporting their results and introducing a novel model for the forbidden relic density as a function of mass splittings and interaction strengths. I aim to determine masses and interaction strengths of the forbidden DM particle which result in the observed relic abundance of DM to help constrain its parameter space for later use in the design of direct detection experiments.
Erik Pohl ’18
Advisor: Beth Parks
Trace Element Analysis of Airborne Particulate Matter: Uganda
Ambient air pollution (AAP) is an issue that plagues developing countries around the world, posing significant threats to both human and environmental health. Most notably, particulate matter under ten micrometers in diameter (PM10) is responsible for a significant percentage of deaths resulting from various lung and heart diseases. Continuing on previous work done by PhD candidate Silver Onyango and Colgate University Professor Beth Parks, this study begins to evaluate three methods for performing elemental analyses of PM10 samples: total reflection x-ray fluorescence (TXRF), inductively coupled plasma – atomic emission spectroscopy (ICP-AES), and carbon combustion analysis. After analyzing a PM10 sample using the aforementioned technologies, it was determined that these methods showed promise for conducting a fully comprehensive elemental analysis, from which data could be used in future source apportionment studies. The preliminary data obtained this semester provided us with a sound basis for forming hypotheses regarding the composition and sources of our samples. However, given the short time frame of this study and the limited prior knowledge on the subject, apparatus, and analysis process, the results of this study still provide a great deal of room for improvement.
Zoe Sale ’18
Advisor: Rebecca Metzler
Exploring the Materials Properties of the Eastern Oyster
The Eastern Oyster (Crassostrea Virginica) forms a reef by creating an adhesive, which allows the oyster to stick to other oysters, and substrates in its environment. These reefs play a vital role in protecting ocean ecosystems. Oysters extract their food from the water by filter feeding, cleaning up to 50 gallons of water per day, promoting better habitats for other organisms. The reefs also provide protection from storm surges, as their adhesive is strong enough to absorb storm energy but flexible enough to move so that the reef stays intact. And yet despite all we know about the Eastern Oyster, how exactly it creates this adhesive and how it affects the shells of the organism that produces it remains a mystery.
Rishav Sharma ’18
Advisor: Kiko Galvez
Sorting of molecular chirality using chiral light: Observing optical activity in liquid crystals
We aim to differentiate between chirality of molecules using polarized light. The change in the polarity of the light occurs due to its interaction with the chiral molecule. This interaction is known as optical activity. So, our efforts over the semester have been spent in observing optical activity by designing objects that will interact with chiral light and let us observe optical activity. We have discovered that liquid Crystals can be made to act like chiral molecules by the addition of a dopant that gives them a specific handedness. The liquid crystals are birefringent and by using polarizers in succession, we were able to observe optical activity in liquid crystals.
Derek Sherry ’18
Advisor: Walter Tangarife Garcia
Partially Interacting Dark Matter and Dark Disk Formation
Many observations have provided evidence for the existence of dark matter. However, the most studied candidate for this dark matter, the WIMP, is looking increasingly improbable as more and more experiments fail to find it. It is possible that as much as 5% of the dark matter in the universe is actually has strong self-interactions. This is known as partially interacting dark matter (PIDM). Through its interactions, PIDM could cool and form a dark galactic disk similar to the baryonic disks that we can observe today. The existence of such a disk may provide new means for detecting the signature of dark matter.
Nolan Smyth ’18
Advisor: Walter Tangarife Garcia
Fuzzy Cold Dark Matter
Much of our current understanding of dark matter (DM) stems from numerical simulations of the large scale structure of the universe and observations of dark matter-dominated halos. For many years, the Weakly Interacting Massive Particle (WIMP) has been the most prominent candidate put forth as a model of DM. However, this paradigm is currently shifting due to conflicts with the current WIMP model and observations of dark matter-dominated dwarf galaxies. In particular, WIMP simulations are not in agreement with the number and matter density of these dwarf halos. In this paper we examine an alternative DM candidate, an extremely light scalar field that shares the successes of the WIMP model while addressing some of its failures. This Fuzzy Cold Dark Matter (FCDM) model is understood by solving the non-relativistic field equations that govern its motion and comparing these results to observational data.
Ryan Stahlin ’18
Advisor: Patrick Crotty
Superheavy Dark Matter Production during Natural Inflation
The search for WIMP-like dark matter is closing in on the limits of experimentally verifiable mass ranges. While most WIMP models propose a mass in the general range of 102 103GeV, it is important to also consider heavier, non-thermal relic particles. In this paper, we examine the gravitational production of such a model of superheavy dark matter, the WIMPzilla, during cosmic inflation using the natural inflation model V (φ) ~ [1 + cos(φ/f )]. WIMPzillas are proposed to be a scalar field with corresponding mass m = 1012 -1016GeV in its vacuum energy state before inflation. Following the non-adiabatic inflation of spacetime, the vacuum energy state would be changed, while the WIMPzilla field remained in its original state. This would effectively result in an excitation in the field corresponding to the production of WIMPzilla particles. We present results from sweeping several different values of m and their respective implications for particle production. Although it appears that WIMPzilla particle production would be unlikely in a natural inflation scenario, past results imply that the search for WIMPzilla production can work with some select inflationary models, and so therefore it is important to continue this process with other inflationary models.
Charles (Hunter) Warburton ’18
Advisor: Kiko Galvez
Liquid Crystal Cell Birefringence Patterns
The birefringence patterns of geometrically surface-anchored nematic liquid crystals are investigated in order to further understand the relationship between an etched pattern on a liquid crystal cell and the polarization pattern that results from monochromatic light passing through it. Discrete geometric surface etching on multiple liquid crystal cell samples allows for the exploration of the resultant polarization patterns using polarimetry.
Dylan Whitbread ’18
Advisor: Linda Tseng
Water Flow and Nutrient Analysis in the Hamilton Watershed
The extent of hypoxia and anoxia (varying degrees of oxygen deprivation in water) in the watersheds of Chesapeake Bay is sufficient enough to cause significant damage to estuarine and coastal ecosystems, threaten water resources (such as groundwater) and be inherent in the formation of desired conditions for the processes of eutrophication and, more severely, acidification. Whilst hypoxic zones (known as dead zones) have occurred historically, the rate at which they are currently occurring and growing has not been seen before, and the extent can be attributed to human activity and climate change. Nutrient loading (the excess of nutrients within a water system) is known to be strongly correlated with the occurrence of decreased concentrations of dissolved oxygen within the Chesapeake Bay watershed, and these effects are exacerbated in water systems that contain impoundments (wherein anthropogenic sediment retention occurs). We report here on the findings of papers that outline potential problems that hypoxia and nutrient loading can induce, as well as on the results of our data and sample collection that took place at various locations within the Hamilton watershed. We have sought to determine the flow rate of the water at the various locations using a flow meter and, using ion-exchange chromatography, the respective nutrient load that each location incurs.
Michael Williams ’18
Advisor: Cosmin Ilie
Dark Stars in View of Non-WIMP Dark Matter
In this presentation I will delve into the feasibility of Wimpzilla Dark Matter, a supermassive cousin of the WIMP (Weakly Interacting Massive Particle), in being the dominant source of power over nuclear fusion in stars in the early universe. Many particles under the WIMP umbrella are thought to have properties causing them to be their own anti-particles, and are thus able to annihilate each other at the core of a star to counterbalance the gravitational forces trying to collapse it. A star fueled in this way – a Dark Star – is a theoretical concept that is unique to the low metallicity and DM rich environment of the early universe. The James Webb Space Telescope launching next year will likely be able to detect the existence of these theorized stellar objects, thus giving merit to predictions of how they will look and behave across different DM particle candidates. Much research has been done on WIMP driven Dark Stars due to it being the favorite contender for the true DM particle, but recent failed CERN lab tests predicted to have directly detected them have thus called this ranking into question. It is for this reason that we explore the properties of Wimpzillas with respect to stellar astrophysics to test if and how this alternate DM candidate could sustain hydrostatic and thermal equilibrium in Dark Stars in the early universe. Through various analyses we concluded that any supermassive particle, including Wimpzillas, could not suffice to fuel Dark Stars, and consequently if Dark Stars were in fact observed by the JWST with properties alluding to a DM power source the particle could be removed from contention for the true identity of our universe’s mysterious DM particle.
