Events

Sarah Chinski will present her Senior Honors Thesis online via Zoom.

William Setterberg will present his Senior Honors Thesis online via Zoom.

James Cannon will present his Senior Honors Thesis online via Zoom.

Alyssa Bulatek will present her Senior Honors Thesis online via Zoom.

Andrew Mizener will present his Senior Honors Thesis online via Zoom. 

Dr. Sean Marshall, Postdoctoral Research Scientist, Arecibo Observatory will speak about "Radar Observations of Solar System Objects."

Radar observations provide unique information on solid objects within our solar system, including rocky planets, icy moons, and near-Earth asteroids. With radar, the observer controls the transmitted signal. Radar observations make it possible to see through clouds and into an object's subsurface. Radar data provide very fine measurements of an object's radial velocity and distance, and bright targets can be spatially resolved into images. With a sequence of delay-Doppler images, it is possible to find the target's size, shape, rotation state, and other properties.

Senior Honors Thesis presentation in the Physics & Astronomy Department coming up: 

• Riley McGlasson, "Shape Model of Potentially Hazardous Asteroid (1981) Midas from Radar and Lightcurve Observations."

Refreshments at 3 p.m.

One more Physics & Astronomy Senior Capstone presentation!

• Lilly Bralts-Kelly, "ALFALFA Harvest: HI Imaging and 3D Modeling of Candidate Local Group Dwarf Galaxies."

Refreshments at 3 p.m.

Two more Physics & Astronomy Senior Capstone presentations!

• Hannah Gilbonio ► "Crumpling of Graphene Optimizes Graphene Field Effect Transistors (GFETs) as Biosensors"
  
• Nicholas Moore ► "Large Scale Grid Integration of Wind and Solar Power with Storage"
  

Refreshments at 3 p.m.

More Physics and Astronomy Senior Capstone presentations!

Physics and Astronomy Senior Capstone presentations continue! 

• Jacob Hetrick: "A Search for Pulsars Towards the Galactic Center"
• Brynn Keller: "Searching for Doublet Vector Like Leptons Using the ATLAS Particle Detector"

Refreshments at 3 p.m.

Physics and Astronomy Senior Capstone presentations continue! 

• Elena Youngdale: "Development of High Performance Asphalt Composite for Mitigating Pavement Cracking"

• Nathan Davies: "Modeling Scavenging for a Hydraulic Free-Piston Engine" 

Refreshments at 3 p.m.

Physics and Astronomy Senior Capstone presentations start this week! 

• Anya Wolterman: "Monte Carlo Glauber Modelling of High Energy Pb+Pb and Au+Au Collisions"
  
• Kieran Liming: "Deposition of TiN for Battery and Supercapacitor Electrodes for Energy Storage"
  

Refreshments at 3 p.m.

The Physics & Astronomy Department presents two senior Capstone presentations: Salamong Xiong, "SuperCDMS: Energy Calibration of a Cryogenic Ge High-Voltage Particle Detector;" and Jacob Weightman, "Fabrication on Nanoscale Columnar Diodes by Glancing Angle Deposition."

Snacks at 3 p.m. 

"Systems Engineering: the NASA Perspective," presented by Dr. Mark Thornblom, Program Element Manager in the Game Changing Development Program Office in NASA's Space Technology Mission Directorate.

Systems engineering is at the heart of space exploration. In this virtual seminar, Dr. Thornblom will explore the intersection of physics and engineering using detailed case studies from the Apollo mission, the Space Shuttle, and others. This "engineering for non-majors" seminar paints a picture of how physicists and engineers interact to enable successful exploration.   

Snacks at 3 p.m. 

Mario Affatigato, Professor & Chair, Physics Department, Coe College is presenting.

This presentation will cover the formation and characterization of glasses using aerolevitation . In this method, spherical beads are levitated and melted in a containerless process, avoiding many of the pitfalls of traditional (crucible based) glass making. Aerolevitation can attain high temperatures of up to 3000 degrees C, eliminate contamination, and inhibit heterogeneous crystallization . The talk covers the basic physics, nonequilibrium conditions, stress induced crystallization, and in situ characterization.

We will cover ways to make thermophysical measurements of density, viscosity, and surface tension at high temperatures, as well as some of the nuances of such experiments. Finally, we will discuss novel crystals that can be made thru the use of this technique.

Pizza lunch provided. 

Rachel S. Goldman, Professor, University of Michigan, Department of MSE, EECS, & Physics is presenting.

Highly mismatched "designer" alloys are materials that contain chemical  elements with very different atomic sizes and abilities to attract nearby electrons. When a few atoms with larger or smaller atomic sizes are added to a host material, its electrical and optical properties often change dramatically.

In this talk, we present combined computational experimental studies which enabled our pioneering epitaxy and band structure engineering of GaAs(N):Bi alloys. In addition to describing recent advances in surface reconstruction driven control of solute incorporation and atomic ordering, we present a new “magic ratio” for lattice matching of GaAsNBi with GaAs substrates. We also present a strategy for the synthesis and tailored electronic structure of III V bismuthides for integration with III V based electronics. 

Pizza snack. 

"So What is it Actually Like Being Black/Queer/Transgender in Physics?" Grey Batie, Ph.D. Candidate, UC Berkeley, Department of Nuclear Engineering is presenting. Pizza lunch.

Science is fun, but sometimes it can be lonely if you’re the only one who looks like you in your laboratory. Come to this talk to hear about the stories and experiences of a current queer, black trans graduate student, and how they found their place in their field.

Topics include diversity, inclusion, intersectionality, and how to make the STEM fields a place where everyone feels comfortable, seen, and respected. This session is open to anyone and everyone!

Informal conversation with speaker prior to talk, 10-11:15 AM in 159 OLRI. 

"Methods for Process Monitoring to Accurately Detect and Quantify Material Holdup in Advanced Recycle Facilities." Grey Batie, Ph.D. Candidate, UC Berkeley, Department of Nuclear Engineering is presenting. 

Different stages of the nuclear fuel cycle require different safeguards based on the nuclear material present and its form. For example, in most nuclear fuel reprocessing facilities, nuclear material is handed in bulk form, meaning the material is in a form that is not individually identifiable for accounting purposes (i.e. liquid, gas or powder). It is in these facilities where distinct techniques are vital to the prevention of both inadvertent or deliberate material leaks, or hold-up.

This presentation will explore research conducted at UC Berkeley to develop unique methods to enable the detection of inadvertent or deliberate holdup of special nuclear material within these types of nuclear reprocessing facilities, to ensure the peaceful use of nuclear technology.

Snacks at 3 PM.

Informal conversation with speaker follows talk, 4:30-5:30 PM. 

Michael Rutkowski, Assistant Professor, Minnesota State University - Mankato will present on, "Leveraging Ultraviolet Observations to Understand How Galaxies Drive Evolution on Cosmic Scales." 

Ultraviolet observations of galaxies are critical for solving a variety of fundamental questions in modern astrophysics. I will discuss how a number of past and present UV optical extragalactic surveys provide novel constraints on some of these questions. Specifically, I will highlight the utility of UV observations of 1) OVI emission in the circumgalactic medium of starburst galaxies, 2) star forming galaxies at the rest frame Lyman continuum regime, and 3) quiescent galaxies at intermediate redshift for understanding the cosmic history of metals, reionization of the neutral intergalactic medium, and the hierarchical assembly of galaxies, respectively.  I will conclude with a discussion of some efforts to ensure UV science is sustained or improved in the 2020s and beyond.

Pizza lunch provided. 

The Macalester Observatory will host a special Public Observing Night on Friday, November 8th from 7:00 to 10:00 p.m. This is one of more than 30 such events being held at various sites across Minnesota over the weekend, collectively known as the first ever Statewide Star Party, and is part of a continuing celebration of the 50th anniversary of the Apollo Moon landing. Come to Olin-Rice Room 404 for some fun Moon-related educational activities, and (if clear skies permit) observe the waxing gibbous Moon and other celestial objects through our telescopes. Children and adults of all ages are welcome!

Summer Research Opportunities for Students! Interested in doing physics and astronomy research in summer 2020? Join us for pizza and learn about both on-campus and off-campus summer research opportunities.  We will discuss what options are available and the application procedures.

Find your ideal research project!

Pizza lunch provided.

Interactive Round Table Event with Former Department Members who are now Science Teachers: Hans Harlane '10, Mac post-bac '11-12; Tom Totushek ‘02; Maggie Molter ‘14; Roni Teich, Vassar College '14, Mac post-bac '14-'15.

Recent Macalester graduates who are now science teachers will be our virtual guests. These individuals will share perspectives on their careers as educators and how their undergraduate and Macalester experiences helped them to be prepared to follow that path. This will be a unique opportunity for you to learn from their recent experiences. 

Each of our virtual guests will speak for a few minutes.  Then we will open the floor up for questions and discussion with you. Please come prepared with questions for our guests and topics you would like to discuss. 

Snacks at 3 p.m.

Dr. Vivian Ferry, Assistant Professor, Department of Chemical Engineering and Materials Science, University of Minnesota, is presenting.

The solar spectrum is a broad and diffuse light source, but solar panels operate most efficiently at specific wavelengths near the semiconductor bandgap and over a limited range of incident angles. Different strategies can be used with nanostructured optical materials to enhance the performance of photovoltaics. Luminescent solar concentrators harvest diffuse sunlight, concentrate sunlight onto small-area solar cells, and can be integrated into architectural panels. To create these panels, we synthesize luminescent materials and create nanostructured surfaces to guide light toward the solar cell. In the field, thermal management in photovoltaic modules exhibit decreased performance due to elevated operating temperature. I will discuss the use of nanostructured surfaces to enhance the energy yield of the module by simultaneously reducing the operating temperature and improving photocurrent generation. 

Snacks at 3 p.m. 

Interested in Engineering? Come to this information session with free pizza lunch!

Professors Rebecca Anthony and Sara Roccabianca from the Mechanical Engineering Department at Michigan State University answer your questions about graduate school in engineering. They are eager to share information about their paths from physics into engineering, and also to provide information about the opportunities for graduate study at Michigan State University and in engineering in general.

RSVP to jcannon@macalester.edu by Wednesday, October 9 at noon.

Dr. Craig Taatjes, Distinguished Member of the Technical Staff, Sandia National Laboratory is presenting "Understanding Complex Chemical Systems Step by Step." 

In complex chemical systems, the crucial steps are often reactions of intermediate species formed in previous reaction steps. Often these reactants are formed relatively slowly and may react away rapidly, so it is often difficult to isolate them and study these crucial steps in detail. In our research we have long sought to produce elusive reactive species and directly study their kinetics, focusing on products of the reactions as well as rate coefficients.

In this talk I will discuss a few recent examples of reactions in which the product branching determines consequences of the reaction for applications that are governed by a complex chemical model.

Speaker:  Gordon Dietzman, Naturalist and Photographer

Stretching from northern Minnesota to the Gulf of Mexico the upper Mississippi River is bounded by northern mixed forests, eastern deciduous forests, floodplain forests, and western tallgrass prairies. This rich environment hosts an enormous diversity of wildlife, but that hasn’t always been the case. The river, heavily polluted in the early 1900s, lost its fish, birds were uncommon, and most mammals were missing from the landscape.

The Mississippi River of today is much different than the polluted and impoverished river of a few decades ago. While the river faces emerging challenges, its water and air are cleaner, and we have developed a greater appreciation and tolerance for the wild neighbors which have returned to its waters and shorelines. The photographs of this exhibit capture complex lives poorly in split-second increments but will, hopefully, call us to enjoy the life of this great river in person while prompting us to work to ensure its further recovery.

Gordon Dietzman describes himself as a “curious photographer/naturalist” interested in wildlife, science, and art. He holds a degree in Interdisciplinary Studies (emphasis in environmental interpretation) from the University of Wisconsin. He is currently employed by the National Park Service but also has worked in agriculture, environmental education, the conservation of endangered species, and engineering. His photographic and employment focus is on the upper Mississippi River basin, but he has photographed wildlife and wild landscapes across North America and Southeast Asia.

Refreshments provided.

Dr. Daniel Loveless, Assistant Professor, Department of Electrical Engineering, UT Chattanooga will present a seminar, "Space Radiation and Its Effects on Microelectronic Systems."

A reliability concern of growing interest in the microelectronics community is the deleterious effect of ionizing radiation. The so-called "single events" – single particles which can penetrate semiconductor material leaving ionized charge in their wake – can cause information corruption, transient anomalies, and sometimes irreparable system failure. Single events are ubiquitous; this radiation exists in the environment external to a circuit and emanates from processing and packaging material integral to a circuit. Once only the concern of space-bound systems where increased susceptibilities to single-event effects (SEE) have been reported as device feature sizes decrease and operating frequencies increase, integrated circuit (IC) density and power scaling have propelled this issue to the forefront of reliability concerns at current technology nodes in ground-based and space-deployed electronic systems. This presentation addresses several attributes of IC scaling relevant to radiation degradation, failure modes, and vulnerability. Basic and state-of-the-art approaches for the mitigation of SEEs are presented along with examples of hardened circuits. The presentation concludes with a discussion of the latest techniques for measurement, analysis, and mitigation of transient radiation phenomena, and impacts on future technologies.

Snacks at 3 PM. 

Speaker:  Dr. Dawn Sumner, Professor, Earth and Planetary Sciences, University of CA-Davis

Dawn Sumner is a member of NASA’s Mars Science Laboratory and will talk about her work helping the rover Curiosity explore ancient environments in Gale Crater on Mars.

Dawn Sumner’s research focuses on reconstructing ancient environments on early Earth and Mars and the early evolution of bacteria, including the origin of oxygenic photosynthesis. Her group studies everything from the environmental settings, geochemistry and morphology of Archean microbialites to the morphology, climate response, and genomics of modern microbial communities growing in ice-covered Antarctic lakes to the stratigraphy and geochemistry of sedimentary rocks on Mars. Sumner is a member of NASA’s Mars Science Laboratory, helping the rover Curiosity explore ancient environments in Gale Crater on Mars. She regularly shares her research and adventures with the public. Dr. Sumner is dedicated to helping students of all backgrounds prepare for careers in science as well as to creating educational and work environments that are inclusive and supportive, including through the use of feminist research and theory.

This EnviroThursday is co-sponsored by the Environmental Studies, Biology, Geology, and Physics and Astronomy Departments.

Find out what more of your physics and astronomy colleagues are doing for fun! Students will present research information and findings not related to their capstones or theses.

Snacks at 3.

What are your physics and astronomy colleagues doing for fun? Find out at this seminar! Students will present research information and findings not related to their capstones or theses.

Snacks at 3 in the OLRI first floor Atrium. 

Karen Perez Sarmiento presents the last Physics & Astronomy Capstone talk of the year.  She will speak about her research at Fermilab.

Refreshments at 3:00 PM

Greta Helmel will present her honors thesis, "Recent Evolution of the Eta Carinae Supernova Imposter System."

The supernova imposter Eta Carinae and its surrounding Homunculus reflection nebula have been of great interest for the last several decades. As the most massive star known in our Galaxy, this object is of particular importance in understanding high mass loss episodes and final stages in the evolution of similarly massive stars. Using the most recent set of spectra from the Hubble Space Telescope STIS/CCD, we investigate changes in the behavior of the central star from 2012 to 2018, which indicate an overall brightening and a related decrease in the stellar wind density. Overall, the star appears to be slowing its development in comparison to the rapid changes it exhibited between 2004 and 2010. We also quantify the evolution of the Homunculus nebula, , determining a precise expansion rate and age estimate based on 18 years of STIS observations, one of the longest temporal baselines ever produced for this object using a single instrument. 

Refreshments at 3 PM.

The Physics & Astronomy Department presents two more senior capstones. All are welcome!

Robert Ford ► The Neutral Hydrogen Kinematics of the Dwarf Galaxy Merger NGC 3239;

Sarah Taft ► Haro 11, Pox 186, and VCC 1313: The Enigmatic Behavior of HI Non-Emitters.

Refreshments at 3 p.m.

The Physics & Astronomy Department presents more senior capstones:

• Ramon Molina, "Investigation on the Electrical  Properties of CdO/ZnO thin films using THz Spectroscopy" 


• Robert Ford, "The Neutral Hydrogen Kinematics of the Dwarf Galaxy Merger NGC 3239"

Refreshments at 3 p.m.

Dr. Anna Williams, Visiting Assistant Professor, Macalester College, will present this seminar.

Galaxies are permeated with magnetic fields at all scale lengths--from protostellar disks to spiral arms.  But how galaxies first acquired magnetic fields, and, in turn grow and sustain large-scale magnetic structures is not well understood.  One way to unravel this problem is by observing magnetic fields in a variety of galaxy environments. Luckily, new and upgraded radio telescopes are providing a new window to the polarization universe, and greatly enhancing our ability to probe astrophysical magnetic fields. I will present the results of three observational studies focused on the coevolution of magnetic fields and galaxies in different environments: (1) a nearby spiral galaxy, NGC 6946, (2) a loose galaxy group, NGC 2563, and (3) distant disk-like galaxies at z~0.5.

Pizza provided.

The Physics & Astronomy Department presents its senior capstone presentations.

• Sam Hollenbach, "Understanding Solar Activity During the Last 400 Years"


• Kelly Flugaur-Leavitt, "Carrier Mobility of Bismuth-Doped Perovskites"


• Dona Pantova, "UV LED Photoluminescence Measurements on GaN Sample"

Refreshments at 3:00 PM.

The Physics & Astronomy Department presents a seminar titled "Electric-Magnetic Duality and its Modern Descendants," by Dr. Kevin Setter, Visiting Assistant Professor, Haverford College. 

In the subject of electromagnetism, we learn that space is filled with a set of two arrows, the electric field and the magnetic field, the fluctuations of which are governed by a set of four Maxwell Equations. The form of these equations remains almost the same if one exchanges the electric field everywhere with the magnetic field. This simple observation turns out to lead to far-reaching implications for both modern physics and modern mathematics. In my talk, I will discuss the phenomenon of electric-magnetic duality, its generalization to nonabelian gauge theories, and surprising interconnections between physics and mathematics that have been uncovered in recent years. 

Snacks at 3 PM

Dr. Thomas Finzell, post-doctoral research fellow, University of Michigan, will present "Classical Novae, Gamma-Rays, and Computation in Physics: The Work of a Transient Astronomer and Physics Educator."

Classical novae are thermonuclear events that occur on the surface of white dwarfs (burnt out stellar cores), and for nearly 40 years astronomers thought they had them figured out. But eight years ago, something unexpected happened: astronomers discovered some classical novae emit extremely energetic gamma-rays. In this talk, I will discuss how our understanding of classical novae has changed dramatically in the last decade, the new physics incorporated into our model that explain the presence of gamma-rays, and my role in effecting those changes. I will end my talk by discussing my transition from astrophysics to physics education research, and my current work studying how we can improve the way we teach physics by integrating computation into the classroom.

Interactive Graduate Student Round Table Event! During this class period, multiple recent Macalester graduates who are now in graduate programs will be our virtual guests.  These individuals will share perspectives on the realities of graduate school, from determining where to apply to succeeding once there.  This will be a unique opportunity for you to learn from their recent experiences. 

There will not be a rigid schedule for this event.  Each of our virtual guests will speak for a few minutes about their path and their experiences.  Then we will open the floor up for questions and discussion with you. Please come prepared with questions for our guests and topics you would like to discuss. 

Snacks at 3 PM

Dr. Michael Rutkowski, Assistant Professor, Minnesota State University Mankato, will present a seminar "UV Astronomy: Are we entering a new Dark Age?"

Ultraviolet observations of galaxies are required to solve a number of fundamental, unanswered questions in modern astrophysics. In this topical seminar, I will discuss a number of UV-optical-near IR surveys that provide novel constraints on some of these outstanding questions. Specifically, I will highlight the utility of UV observations of 1) OVI emission in the circumgalactic medium of starburst galaxies, 2) star-forming galaxies at the rest-frame Lyman continuum regime, and 3) quiescent galaxies at intermediate redshift for understanding the cosmic history metals, reionization, and the hierarchical assembly, respectively. I will conclude with a discussion of efforts to develop new, and extend the life of existing, UV assets in space into the 2020s and (hopefully) beyond. 

Snacks at 3 PM. 

The Physics & Astronomy Department presents a seminar by Dr. Joachim Hossick-Schott, Bakken Fellow and Technical Fellow, Medtronic.

The surface was invented by the devil, according to Wolfgang Pauli. Therefore, understanding the processes between an electrode surface and adjacent media continues to be a scientifically challenging theme for many research teams around the world. The laws of physics and chemistry at the interface between an electrode surface and adjacent media determine the working principles of batteries and electrolytic capacitors. These components find ubiquitous use as electrical power sources in many electrical devices, for example in cell phones. The purpose of this talk is to highlight the surface physics and interfacial electrochemistry in batteries and electrolytic capacitors designed specifically for use in implanted medical devices.

Snacks at 3 PM.

Dr. Richard Anthony D'Souza, Postdoctoral Researcher, University of Michigan, presents this seminar sponsored by the Physics & Astronomy Department.

Although galaxy merging and interactions are the key, distinctive features of our picture of galaxy formation in a hierarchical Universe, they have nonetheless played a peripheral role in our observational understanding of disk-dominated Milky Way-mass galaxies. The Andromeda Galaxy (M31), our nearest large galactic neighbour, offers a unique opportunity to test how mergers affect galaxy properties. M31's stellar halo caused by the tidal disruption of satellite galaxies is the best tracer of the galaxy's accretion history. Despite a decade of effort in mapping out M31's large stellar halo, we are unable to convert M31's stellar halo into a merger history. Here we use cosmological models of galaxy formation to show that M31’s massive and metal-rich stellar halo containing intermediate age stars implies that it merged with a large (M* ~ 2.5 x 10^10 M_sun) galaxy ~2 Gyr ago.