Department of Physics and Astronomy

University of Mississippi

Events

  • Tue
    17
    Nov
    2015
    6:00 pmLusa Bakery Bistro and Bar

    Curved space-time:
    Celebrating the 100th Anniversary of General Relativity

    Dr. Katherine Dooley,
    Department of Physics and Astronomy,
    University of Mississippi

    November 1915 was a revolutionary month in the history of science. Einstein published a series of four papers, week upon week, culminating with his presentation of the field equations of General Relativity. He told us that what we thought we knew about gravity from our everyday
    experience is not the whole story. Gravity is the result of massive objects warping space and time. After 100 years, his theory has survived a series of continuous tests of its validity. I will tell some of the early story of Einstein's rise to becoming a pop star and show examples of some of the bizarre consequences of his theory.

  • Tue
    16
    Feb
    2016
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Katherine Dooley and Marco Cavaglià
    Department of Physics and Astronomy
    University of Mississippi

    Observation of Gravitational Waves from a Binary Black Hole Merger.

    On September 14, 2015 at 03:50:45 a.m. CST the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a
    transient gravitational-wave signal. The signal matches the prediction of
    general relativity for the coalescence of two black holes weighting about
    30 Suns into a single black hole at a distance of over one billion light
    years from Earth. This is the first direct detection of gravitational
    waves and the first observation of a binary black hole merger.
    See this page for details.

  • Tue
    08
    Mar
    2016
    4:00 pmLewis Hall 101

    Ken Bader
    Department of Internal Medicine
    University of Cincinnati

    Mechanical Ablation of Tissue with Focused Ultrasound

    Histotripsy is a transcutaneous focused ultrasound therapy that ablates tissue through the mechanical oscillations of microbubbles, or cavitation. Preclinical studies have found histotripsy effective for the treatment of prostate pathologies, cancer, deep vein thrombosis, and congenital heart disease. In this talk, the forms of histotripsy and their ablative mechanisms will be modeled in silico, and image-guidance techniques for mechanical ablation will be discussed. An analytic model will be presented to predict the extent of the treatment zone. This analytic model can be used for treatment planning, and to aid the FDA in the development of regulatory standards for histotripsy. Image-guidance of histotripsy will be demonstrated with a new ultrasound imaging modality called passive cavitation imaging (PCI). Studies in a prostate phantom demonstrate that PCI correlates well with the width of the ablation zone, indicating PCI can be used as a predictive metricfor tissue ablation from histotripsy. Finally, PCI will be used to monitor cavitation when histotripsy is used in combination with a lytic agent to lyse clots in a model of deep vein thrombosis. A significant improvement was observed in the thrombolytic efficacy for the combination treatment over histotripsy alone, suggesting a synergistic effect between histotripsy and the lytic agent.

  • Sun
    20
    Mar
    2016
    7:40 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • March 20, Sunday, 7:40 - 10:00 PM

    We plan to observe  the Moon,  nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    22
    Mar
    2016
    4:00 pmLewis Hall 101

    Thomas Sotiriou
    School of Physics & Astronomy
    University of Nottingham

    Black Holes Without Relativity

    Lorentz symmetry is central to the concept of a black hole, as it precludes superluminal motion. It is not obvious that one can even define what a black hole is if Lorentz symmetry is abandoned, so one might expect that any observational evidence supporting the existence of black holes will impose very stringent constraints on Lorentz violations. I will discuss some basic aspects of causality in theories that violate Lorentz symmetry and I will argue that, remarkably, the concept of a black hole survives in these theories. After defining the appropriate notion of black hole, I will explore their basic aspects and discuss how they differ from black holes in General Relativity.

  • Tue
    22
    Mar
    2016
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Joel Mobley
    Department of Physics and Astronomy
    University of Mississippi

    The physics of MRI

    Magnetic resonance imaging (MRI) has revolutionized the diagnosis and treatment of a broad spectrum of medical conditions. Since its clinical debut in the 1980ʼs, it has evolved to provide a level of anatomical detail not possible with any other imaging modality, all without the focus of an ultrasound probe or the directionality of an x-ray beam. The fundamental principles at work in MRI include quantum physics, spinning tops, flipping magnets and simple patterns of bright and dark. The aim of this talk is to remove some of the mystery of how the manipulation of the weakest
    magnets in the atom leads to the MR image and to look at emerging medical treatments enabled by
    MRI.

  • Tue
    29
    Mar
    2016
    4:00 pmLewis Hall 101

    Richard Brito
    Gravitation in Técnico
    Instituto Superior Técnico — CENTRA

    Interaction Between Bosonic Fields and Compact Objects

    Fundamental bosonic fields generically arise as possible dark matter candidates and in extensions of General Relativity, but are also a useful proxy for more complex interactions. In this talk I will discuss the rich phenomenology of fundamental bosonic fields around black holes and compact stars. In particular I will discuss: (i) the interaction of self-gravitating bosonic structures with compact stars; (ii) superradiant instabilities around black holes and how it can be used to constrain particle masses.

  • Tue
    05
    Apr
    2016
    4:00 pmLewis Hall 101

    Pengfei Zhang
    Department of Mathematics
    University of Mississippi

    Homoclinic Intersections for Geodesic Flows on Convex Spheres

    Transverse homoclinic intersection was discovered by Poincare in the study of stability properties of periodic orbits of n-body problem. Poincare realized that this is a mechanism which not only destroys the stability of periodic orbits but also leads the existence of chaos in the phase space.

    In this talk, we will study the geodesic flows on convex spheres. We show that, generically, every closed geodesic is either hyperbolic or irrationally elliptic. Moreover, every hyperbolic closed geodesic admits some transverse homoclinic intersection. Therefore, (everywhere) chaotic dynamics can happen generically on manifolds with simple/trivial topology.

  • Tue
    12
    Apr
    2016
    4:00 pmLewis Hall 101

    Greg Dooley
    Kavli Institute for Astrophysics and Space Research
    Massachusetts Institute of Technology

    Tidal Stripping with Self-Interacting Dark Matter

    Self-interacting dark matter (SIDM) postulates that dark matter is not entirely collisionless, but self scatters at a low rate. By transforming dark matter halo cusps to cores, SIDM offers a solution to the “too big to fail” problem and cusp/core problem in the Milky Way and local field. Two classes of models exist, with velocity-independent and velocity-dependent cross sections. While tight constraints exist on velocity-independent models, constraining velocity-dependent models remain elusive. In this talk, I discuss the implications of both types of SIDM on the tidal disruption of satellite galaxies in a Milky Way-like host. While the total dark matter mass loss rate is not affected, stellar mass loss is enhanced due to lower binding energy in subhalo cores. I discuss the variables affecting the strength of the increased stellar mass loss rate, the effect on observables in the Milky Way, and where we need to look to further constrain or identify self-interacting dark matter.

  • Sun
    17
    Apr
    2016
    8:00 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • April 17, Sunday, 8:00 - 10:30 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    19
    Apr
    2016
    4:00 pmLewis Hall 101

    Alexander B. Yakovlev
    Department of Electrical Engineering
    University of Mississippi

    Non-local Susceptibility of the Wire Medium in the Spatial Domain Considering Material Boundaries

    The interaction of electromagnetic waves and wire media has been of interest for many years, driven by applications utilizing artificial plasma, epsilon-near-zero materials, negative refraction, wave canalization and other uses. When the period of the wires is small compared to wavelength, the structure can be considered as a homogeneous (homogenized) medium. Early models of wire media neglected spatial dispersion of the homogenized material, but it has more recently been shown that non-local effects are verystrong for wire media and often cannot be ignored.

    In this work, we show that the non-local susceptibility for a nontranslationally invariant homogenized wire medium is, modulo a constant, given by a simple Green's function related to the material geometry. We also show that two previous methods for solving wave interaction problems for bounded wire media (wave expansion method and transport equation) are equivalent to each other, and to a third method involving particle reflection at the boundary. We discuss the importance of the dead layer or virtual interface, and find it to be analogous to the excitonic semiconductor case. Several examples are provided to clarify the material.

  • Tue
    26
    Apr
    2016
    4:00 pmLewis Hall 101

    Ahmed Rashed
    Department of Physics and Astronomy
    University of Mississippi

    Non-standard Tau Neutrino Interactions

    We now know that neutrinos have masses and that there is a leptonic mixing matrix just as there is a quark mixing matrix. The existence of neutrino masses and mixing requires physics beyond the standard model (SM). Hence, it is not unexpected that neutrinos could have new interactions beyond the standard model, or non-standard interactions (NSI). The effects of NSI have been widely considered in neutrino phenomenology. Bounds have been set on the NSI parameters. I will discuss the impact of the NSI on the measurement of neutrino mixing parameters such as the atmospheric and reactor mixing angles, mass hierarchy, and CP violation. We include form factor effects in our calculations and find the deviation of the actual mixing angle from the measured one, assuming the standard model cross section, can be significant and can depend on the energy of the neutrino.

    A key property of the SM gauge interactions is that they are lepton flavor universal. Evidence for violation of this property would be a clear sign of new physics (NP) beyond the SM. Recently, hints of lepton flavor non-universality emerged from B-meson decay channels observed in the BaBar and LHCb experiments. We proposed tests of lepton flavor non-universality in tau-neutrino scattering. Different models have been introduced in this study of which charged Higgs, W', and Leptoquark.

  • Tue
    26
    Apr
    2016
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Breese Quinn
    Department of Physics and Astronomy
    University of Mississippi

    Particle Physics: The Sledgehammer and the Tweezer

    Particle physics is the field of research that seeks to discover and understand the most fundamental building blocks of the universe, and how they interact to form everything around us. One way to do this type of research is using the biggest machines in the world to smash particles together as hard as possible, and see what new comes out. We will take a look at the discovery of the Higgs Boson to examine this sledgehammer approach. Another method is using very sensitive tools to make high precision measurements of extremely rare processes. An introduction to the new Muon g-2 experiment will demonstrate this tweezer approach. We will discuss Ole Missʼ role in both of these efforts, as well as why it all matters.

  • Mon
    09
    May
    2016
    Sunrise - 2 PMKennon Observatory

    The planet Mercury will pass in front of the Sun, which is called a transit. This will start before Sunrise at 6:12 AM and end at 1:42 PM (CDT). It will be most visible about 10 AM. However, since this requires looking directly at the sun appropriate filters or a projection system must be used.

    The physics and astronomy department is hosting an open house at the Kennon observatory next Monday (May 9th) to observe the transit of Mercury occurring that morning. The public is invited to see this relatively rare event through filtered solar telescopes, as it is dangerous to look directly at the sun.

    The open house will will begin at 9 AM and end around noon unless inclement weather makes it impossible to watch the event. Come with your family and friends to watch the Sun and the passage of Mercury across the face of the Sun.

  • Tue
    10
    May
    2016
    11:00 amLewis Hall 101

    The 2016 induction ceremony for the National Physics Honors Society, ΣΠΣ will take place on May 10 at 11:00 AM in room 101 in Lewis Hall.

  • Sat
    14
    May
    2016
    11:30 am - 1:00 pmLewis Hall room 104

    The Department of Physics and Astronomy is hosting a buffet luncheon honoring the 2016 graduating students.  Family and friends are invited to attend.

    Undergraduates:
    Forrest N. Gamble
    Jeffrey D. Atkinson
    Piero R. Bracamonte
    Hunter A. Gabbard
    Peshani Herath
    Jared K. Wofford
    Graduates:
    Shanmuka Shivashankara - Ph.D.
    Sumudu P. Tennakoon - Ph.D.
    Salman Allahiad - M.A.
    Mohsen Rezaeizaheh - M.A.
    Nazanin Omidi - M.S.  (August)

  • Mon
    06
    Jun
    2016
    Tue
    07
    Jun
    2016
    9:00 AM – 4:00 PMJackson Avenue Center, G08, University of Mississippi, Oxford

    Two-day workshop, teachers will learn the basics of sound waves, light waves, and gravitational waves, a new kind of wave that has recently been observed for the first time. See http://umcmse.com/waves-here-there-and-everywhere/ for details.

  • Mon
    27
    Jun
    2016
    Tue
    28
    Jun
    2016
    9:00 a.m. - 5:00 p.m.Lewis Hall, University of Mississippi

    The department is hosting a 2 day QuarkNet Teacher Workshop on June 27 and June 28.  We will discuss the detection of Dark Matter, SuperSymmetry, and Cosmic Rays.  Teachers will learn how to operate cosmic ray detectors and take activities back to their class rooms. Contact the Department of Physics and Astronomy if you are a high school Physics teacher and are interested in the QuarkNet program.

    You can find more out about QuarkNet at the wiki site:   https://en.wikipedia.org/wiki/QuarkNet

    (For more information please contact Dr. Cremaldi at cremaldi@phy.olemiss.edu)

     

  • Sun
    10
    Jul
    2016
    8:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • July 10, Sunday, 8:30 - 11:00 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    30
    Aug
    2016
    4:00 pmLewis Hall 104

    Ice Cream Social

  • Sun
    11
    Sep
    2016
    7:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • September 11, Sunday, 7:30 - 10:00 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    13
    Sep
    2016
    4:00 pmLewis Hall 101

    Michael S Turner
    Kavli Institute for Cosmological Physics
    University of Chicago

    The Big Picture:  What We Know About How the Universe Began and What We Are Trying to Find Out

    Today the Universe is made out of dark matter, dark energy and a small amount of ordinary matter (the atoms we are made of).  We can trace the history of the Universe back to when it was a microsecond and was a formless quark soup.  We now have good evidence for an early burst of tremendous expansion (inflation) that stretched sub-atomic quantum fluctuations to astrophysical size and created the seeds for galaxies.  But there is much to figure out, including what dark matter is made of, what the nature of the mysterious dark energy is, and when inflation took place.

  • Tue
    13
    Sep
    2016
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Michael S Turner
    Kavli Institute for Cosmological Physics
    University of Chicago

    Einstein's Outrageous Universe: Gravitational Waves, Black Holes and the Big Bang

    Dr. Michael Turner, Bruce V. & Diana M. Rauner Service Professor of Physics and Astronomy and Director of the Kavli Institute at the University of Chicago will discuss the biggest mysteries of modern cosmology. Is the universe finite or infinite? What is speeding up the expansion of the universe? Turner will present the current state of knowledge about modern cosmology, from the discovery of cosmic expansion to dark matter and dark energy.

     

  • Tue
    20
    Sep
    2016
    4:00 pmLewis Hall 101

    Don Summers et al.
    Department of Physics and Astronomy
    University of Mississippi

    Fascinating Physics Demonstrations

    Fifty minutes of fascinating physics demonstrations, including milk jug rockets, will be presented.

  • Tue
    27
    Sep
    2016
    4:00 pmLewis Hall 101

    Don Summers Presenting
    Department of Physics and Astronomy
    University of Mississippi

    Powers of Ten

    Powers of Ten illustrates the universe as an arena of both continuity and change, of everyday picnics and cosmic mystery. It begins with a close-up shot of a man sleeping near the lakeside in Chicago, viewed from one meter away. The landscape steadily moves out until it reveals the edge of the known universe. Then, at a rate of 10-to-the-tenth meters per second, the film takes us towards Earth again, continuing back to the sleeping man's hand and eventually down to the level of a carbon atom.

  • Sun
    09
    Oct
    2016
    7:00 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • October 9, Sunday, 7:00 - 9:00 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    11
    Oct
    2016
    4:00 pmLewis Hall 101

    Mike Reep and Scott Watkins
    Dept. of Physics and Astronomy
    University of Mississippi

     

    Machine Shop Physics

     

    Abstract

    Experimental physics depends on instrumentation made in the University of Mississippi's Physics machine shop.  Instruments made for Acoustics, Atmospheric physics, Condensed Matter physics, and Particle physics will be shown.

     

  • Tue
    11
    Oct
    2016
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Arne – R. Diercks,
    School of Ocean Science and Technology
    University of Southern Mississippi

    Perpetual Snow - Sedimentation in the Deep Sea

    Sedimentation in the deep ocean is a slow and steady supply of material to the deep sea via small particles. Once glued together by organic matrices into larger aggregates, they become a main source of energy, food and sediments in the deep sea and the seafloor. Sedimentation rates in the deep ocean are small, ranging from a fraction to a few millimeters per year in the abyssal ocean. Anthropogenic impacts can alter the sedimentation even in remote areas. Following the Deep Water Horizon Oil Spill in the northern Gulf of Mexico, anthropogenic oil marine aggregates that had formed in the water column near the wellhead, were deposited as an unprecedented large amount of material on the seafloor within a few months following the spill.

  • Tue
    18
    Oct
    2016
    4:00 pmLewis Hall 101

    Chandrima Chatterjee
    Department of Physics and Astronomy
    University of Mississippi

    Experimental Investigation of Impurities and Their Effect on Acousto-Electric Properties of Lithium Niobate

    The functional parameters of Lithium niobate that is used in various acousto-opto-electronic applications are questionable. The nonclassical nonlinear effect such as “acoustical memory” is not explained at full. Despite there being publications on crystal defects in Lithium niobate, the relationship between the defects and Acoustical Memory has not yet been established. Previous publications analyzed the Acoustical Memory effect without going into the microstructural detail of the level of point defects. The purpose of this research is to establish a connection between the microscopic point defects and the macroscopic nonlinear phenomena. The present research aims at finding new crystal characteristics including the identification of impurities and point defects, the distribution of the defects along the optical crystallographic z axis, and in a direction normal to the z axis. Bulk crystals and wafers are studied. The impurities are identified by their characteristic lines in the photoluminescence spectra, which are taken at room temperature in a range of 350 to 900 nm. The spectra reveal the following point defects: Ar, Ba, Cs, F-color center, Rb, Ru, Sn, Fe, K, Li, O, Nb, Kr, NbLi4+, Xe, etc. The peak corresponding to the F-center is found at 400.429 nm and has the highest number of photon counts. Further, the samples are shifted with a step of tens of microns along the z-axes or normal to it. This optical scanning allows to find a distribution of the impurities in the samples. The photon counts changes with crystal position for some impurities. The distribution of these defects is observed as peaks and valleys. The results may be used to discover the physical mechanisms behind nonclassical nonlinear phenomena in Lithium niobate.

  • Tue
    25
    Oct
    2016
    4:00 pmLewis Hall 101

    Matteo Rini
    Deputy Editor
    American Physical Society

    Science Communication: Take Charge of It!

    Scientists have a responsibility to share the meaning and implications of their work, but receive little training in communication, and often feel unprepared to communicate with the public, the media, public officers and others outside their own field. In this talk, I will discuss how our journal Physics (htttp://physics.aps.org) strives to communicate research to a broad audience and share some thoughts and tips on science communication from my experience as a writer, editor, press officer and scientific consultant to policy makers.

  • Fri
    28
    Oct
    2016
    7:00 pmLewis Hall

    Frights, food and fun are the order of the evening when the University of Mississippi Department of Physics and Astronomy presents "Spooky Physics Demonstrations" from 7 to 9 p.m. Friday (Oct. 28) in Lewis Hall.

    The program will include a stage show at 8 p.m. Hands-on activities for the public through the evening include freezing objects in liquid nitrogen (at minus 320 degrees), generating sound waves with Bunsen burners and tubes, and levitating magnets with superconductors. Other fun presentations include optical illusions with mirrors, a Van de Graaff generator (a literally “hair-raising” electrical device), a bed of nails and other contraptions.

    Physics department personnel also will prepare ice cream with liquid nitrogen and award prizes for the most original, scariest and cutest costumes to kids aged 12 and under.

  • Tue
    01
    Nov
    2016
    4:00 pmLewis Hall 101
    Jeremy Sakstein
    Department of Physics and Astronomy
    University of Pennsylvania

    Novel Tests of Gravity Using Astrophysics

    The expansion of the Universe is accelerating and we have little to no idea why! This has led to a proliferation of alternative theories of gravity that are not general relativity as one possible explanation. Classical alternatives are quickly ruled out by solar system tests but modern theories can evade them by utilising screening mechanisms. This has led to an active program developing new and novel tests of gravity by looking for objects that are not fully screened.

    In this talk, I will review the cosmological constant problem and modern alternative gravity theories before going on to describe some of my work looking for new and novel ways of testing gravity using objects such as dwarf stars, neutron stars, and pulsating Cepheids.

  • Sun
    06
    Nov
    2016
    6:00 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • November 6, Sunday, 6:00 - 8:00 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    08
    Nov
    2016
    4:00 pmLewis Hall 101

    Mairi Sakellariadou
    Department of Physics
    King's College — London

    Unweaving the Fabric of the Universe

    Our conventional understanding of space-time, as well as our notion of geometry, break down once we attempt to describe the very early stages of the evolution of our universe. The extreme physical conditions near the Big Bang necessitate an intimate interplay between physics and mathematics. The main challenge is the construction of a theory of quantum gravity, the long-sought unification of Einstein's general relativity with quantum mechanics. There are several attempts to formulate such a theory; they can be tested against experimental and observational results coming from high energy physics and astrophysics, leading to a remarkable interplay between gravity, particle physics and cosmology.

  • Fri
    11
    Nov
    2016
    4:00 pmLewis Hall 109
    Gregory Cook
    Department of Physics
    Wake Forest UniversityGravitational Waves from Colliding Black Holes: An Historical Perspective

    The landmark first direct detection of gravitational waves was announced on Feb. 11, 2016. The detection itself occurred on Sept. 14, 2015 and was the result of the collision of two black holes that happened around a billion years ago. The event marks a turning point in decades of work by hundreds of researchers. The goal of this talk is to provide at least a partial historical account of the research that lead to the detection and interpretation of this event. As a numerical relativist, my perspective will emphasize the work aimed at simulating black-hole collisions on computers. I have been involved in all aspects of the simulation of black-hole binary collisions for nearly 3 decades, with my work focusing primarily on the modeling of initial data for the simulations. However, I will try to give fair coverage of the broader theoretical and computational work involved, and a taste of the experimental milestones leading up to the detection. If time allows, I will also discuss some of my recent work exploring the ring-down signal produced by numerical simulations.

  • Tue
    15
    Nov
    2016
    4:00 pmLewis Hall 101

    Karelle Siellez
    Center for Relativistic Astrophysics
    Georgia Institute of Technology

    The Coincidence Between Gamma-Ray Bursts and Gravitational Waves: the Dawn of the Multi-Messenger Era!

    Last year, while we celebrated the 100th anniversary of the Theory of the General Relativity of Einstein, we also detected the first direct observation of Gravitational Waves. LIGO opened the new area of Gravitational Wave Astrophysics with the detection of the coalescence of two black holes. Neutron star mergers (either double neutron star or neutron star - black hole systems) and collapsing massive stars are the next candidates for the detection of Gravitational Waves. They are though to be also the progenitor of respectively short and long Gamma-Ray Bursts. A detection in coincidence of both the Gravitational Waves and the electromagnetic emission would open the era of multimessenger astrophysics.

    To detect those coincidences between GRB and GW, LIGO uses a different analysis that searches for a GW triggers coincident within some time window and sky position of a GRB in nearly real time thanks to the GCN sent by the satellite. We estimated the rate of coincident events that could be detected during the next run of O2 using observations in one hand and Monte Carlo simulations on the other. The small number of coincidence could be improved by using the untriggered GRBs missed by the Fermi GBM satellite. Thanks to a new code developed by the GBM team, we will discuss about the new kind of coincident detection that we could obtain.

    This talk will describe the search of Gravitational Waves associated to GRBs. We will show the motivations and analysis made for the untriggered searches as well as the implication of those untriggered GRB on the expected rate of coincident event, the classification of long and short GRBs, and the possible new kind of progenitor for short GRBs at low redshift.

  • Sun
    04
    Dec
    2016
    5:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • December 4, Sunday, 5:30 - 7:30 PM

    We plan to observe  the Moon,  planets, nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    24
    Jan
    2017
    4:00 pmLewis Hall 101

    Hartmut Grote
    Division of Laser Interferometry and Gravitational Wave Astronomy
    Albert Einstein Institute — Hannover, Germany

    The Physics of Climate, the IPCC, and the Public Discourse:
    A Tour D'Horizon of Global Warming

    Global warming is a topic of broad scientific inquiry as well as societal relevance. I will review the basic principles of climate physics, explain the role of the IPCC in assessing different aspects of global warming, and will try to shed some light on the public discourse around global warming and forces trying to obstruct the science.

  • Tue
    24
    Jan
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Randy M. Wadkins
    Department of Chemistry and Biochemistry
    University of Mississippi

    It’s a Small World After All
    Nanomaterials are types of matter that lie in size between single molecules and bacteria, or approximately one millionth of a millimeter. Where do you find such tiny little objects? Right in plain sight! Maybe you were hungry today and grabbed a slice of American Cheese or a tub of Greek yogurt from the fridge. Maybe afterward you brushed your teeth with toothpaste, or freshened your breath with gum. Maybe you took a shower and used a dandruff shampoo, then put on deodorant. Maybe you then put on stain-resistant pants, dabbed on a little sunscreen, and headed off to campus. All of those items I just mentioned contain nanoparticles, so small you can’t see each one, but essential for product performance.

    In this follow-up to my 2016 TEDxUM talk, I will describe what the nanoparticles do in these products, then talk a little about nanoengineering using DNA, with a particular focus on the future of nanomedicine. Like in the movie “Fantastic Voyage,” nanomedicine is close to being reality.
    See this page for details.

  • Sun
    05
    Feb
    2017
    6:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • February 5, Sunday, 6:30 - 9:00 PM

    We plan to observe  the Moon,  nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    07
    Feb
    2017
    4:00 pmLewis Hall 101

    Mauricio Richartz
    Centro de Matemática
    Universidade Federal do ABC — Brazil

    Analogue Black Holes: Theory and Experiments

    Analogue models of gravity, introduced by Unruh in 1981, have been (for some time now) very helpful towards a better theoretical understanding of several crucial phenomena at the boundary of gravity and quantum field theory. Experimental research on analogue models, however, started only very recently. In this talk, I will explain the basic theory behind analogue models of gravity and how they can be used to mimic important quantum field theory effects in curved spacetimes, like Hawking radiation. I will also focus on some experimental realizations of analogue models of gravity, including one based on surface waves propagating on water. which I have been involved with very recently (arXiv: 1612.06180).

  • Tue
    14
    Feb
    2017
    4:00 pmLewis Hall 101

    Graduate Students
    Department of Physics and Astronomy
    University of Mississippi

    Temperature Dependent Behavior of Shear Waves in a Micellar Fluid (Sunethra Dayavansha)
    Development of Brain Tissue-Mimicking Phantom (Somayeh Taghizadehghahremanloo)
    Negative Refraction and Super-resolution by a Steel-methanol Phononic Crystal (Ukesh Koju)
    Development of a Tilt-free Seismometer (Reza Afrough)
    The RKKY Interaction for Link Variables on the Square Lattice (Huu Do)
    Experimental Test of an Omnidirectional Acoustic Enhancement Method (Maryam Landi)
    Deforming the Fredkin Spin Chain Away from its Frustration-free point (Khagen Adhikari)

  • Tue
    21
    Feb
    2017
    4:00 pmLewis Hall 101

    Maarten Buijsman
    Division of Marine Science
    University of Southern Mississippi

    The Equatorial Pacific "Graveyard" for Semidiurnal Internal Tides: Incoherence or Dissipation?

    The jets in the equatorial Pacific Ocean of a realistically-forced global circulation model with a horizontal resolution of 1/12.5 degree yield a strong loss of phase coherence in semidiurnal internal tides that propagate equatorward from the French Polynesian Islands and Hawaii. This loss of coherence is determined with a baroclinic energy analysis, in which the semidiurnal-band terms are separated into coherent, incoherent, and cross terms. For time scales longer than a year the coherent energy flux approaches zero values at the equator, while the total flux is 500 W/m. The time-variability of the incoherent energy flux is compared with phase speed variability computed with the Taylor-Goldstein equations. The variability of monthly-mean Taylor-Goldstein phase speeds agrees well with the phase speed variability inferred from steric sea surface height phases extracted with a plane-wave fit technique. On monthly time scales, the loss of phase coherence in the equatorward beams from the French Polynesian Islands is attributed to the time variability in the sheared background flow associated with the jets and tropical instability waves. On an annual time scale, the effect of stratification variability is of equal or greater importance than the background flow is to the loss of coherence. The model simulation suggests that low-frequency jets do not noticeably enhance the dissipation of the internal tide, but merely decohere and scatter it. Thus, the apparent demise of coherent internal tides seen in satellite altimetry maps of the equatorial Pacific may be due to incoherence rather than dissipation.

  • Tue
    21
    Feb
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Susan Pedigo and Lemuel Tsang
    Department of Chemistry and Biochemistry
    University of Mississippi

    Chemistry of Milk

     

    Why is some cheese stringy and other cheese crumbly? We will discuss this topic and others as we tour the chemistry of the proteins, lipids and carbohydrates in milk. Through the millennia, human cultures have exploited one biomolecule or another to create a wide range of foods from milk. We will cover a diverse range of topics including the incredible origin of milk, butter and its close cousin margarine and the art of cheese making.

    See this page for details.

  • Mon
    27
    Feb
    2017
    Thu
    02
    Mar
    2017
    9:00 a.m. - 5:00 p.m.Yerby Conference Center, University of Mississippi

    The “Strong Gravity and Binary Dynamics with Gravitational Wave Observations” workshop convenes Feb. 27 to March 2 in the Yerby Conference Center. The event is supported in part by Emanuele Berti’s National Science Foundation CAREER Award and by a Marie Sklodowska-Curie Research and Innovation Staff Exchange Action network, funded by the European Union’s FP7 program.

    “This network supports exchanges of gravity researchers among the participating nodes,” said Berti, associate professor of physics and astronomy. “In addition to Ole Miss, there are five nodes in Europe, one in in Japan and one in Canada. A dozen researchers will visit campus for a month before and after the workshop.”

    About 50 scientists representing some 30 research agencies and institutions of higher learning are scheduled to attend. Researchers will discuss several topics in the newborn field of gravitational-wave astronomy, including the astrophysics of compact binary populations, spin measurements in compact binaries, strong-field tests of Einstein’s theory of general relativity and how to look for hints of new gravitational physics beyond Einstein’s theory.

    For more about the workshop, visit http://www.phy.olemiss.edu/StronGBaD/. For more about the Department of Physics and Astronomy, go to http://physics.olemiss.edu/.

    Also see the article from Inside Ole Miss.

  • Fri
    03
    Mar
    2017
    4:00 pmLewis Hall 101

    Carlos Herdeiro
    Departamento de Física
    Universidade de Aveiro — Portugal

    Can a Black Hole Have Hair?

    Black holes are one of the most fascinanting predictions of Einstein's theory of General Relativity. In their most paradigmatic guise, they are also the simplest objects in the Universe, made solely of space and time. Moreover, powerful mathematical theorems, known as uniqueness theorems, show that the way space and time can curve into a black hole is quite restricted, and these objects are only described by two parameters: their total mass and angular momentum. John Wheeler famously coined this simplicity into the mantra "Black Holes have no hair". But underlying this statement there is an unproved belief known as the "no-hair conjecture".

    I will start by discussing observational evidence for the existence of black holes in the universe. Then, I will explain why the existence of some simple types of matter, even if Einstein's theory holds, could challenge the no-hair conjecture and produce "hairy" black holes. Finally, I will discuss how ongoing and forthcoming electromagnetic and gravitational waves observations could test the existence of black hole "hair" of this sort.

  • Tue
    07
    Mar
    2017
    4:00 pmLewis Hall 101

    Seth Hopper
    Gravitation in Técnico
    Instituto Superior Técnico — Portugal

    Bound and Unbound Motion Around Static Black Holes

    A massive two-body system will interact gravitationally. Depending on the velocities and separation of bodies, their motion may be bound and periodic (as in the Earth-Sun system) or unbound (like a comet that passes the Sun only once). General relativity predicts that each of these systems will radiate energy in the form of gravitational waves. However, the qualitative difference between the systems implies that different techniques must be used to analyze them. In this talk I will briefly introduce the mathematical theory behind gravitational radiation of two body systems (specifically in the extreme mass-ratio regime) and consider how one can efficiently compute that radiation for different classes of problems.

     

    Andrea Nerozzi
    Gravitation in Técnico
    Instituto Superior Técnico — Portugal

    The Problem of Gauge Fixing in the Newman-Penrose Formalism

    Since its introduction the Newman-Penrose formalism has been widely used in analytical and numerical studies of Einstein's equations, like for example for the Teukolsky master equation, or as a powerful tool for wave extraction in numerical relativity. The problem of gauge fixing, or more specifically, tetrad fixing is however still debated and only partially understood when the NP formalism is used to extract gravitational waves from numerical simulations.

    In this talk I will approach the whole formalism with the goal of finding an invariant expression for all the variables in the NP formalism, namely Weyl scalars and the spin coefficients, once a specific yet generally defined tetrad is chosen.I will show that it is possible to do so, and give a general recipe for the task, as well as an indication of the quantities and identities that are required. The applications and importance of this approach to the problem of wave extraction in numerical relativity will be discussed.

    Laura Bernard
    Gravitation in Técnico
    Instituto Superior Técnico — Portugal

    Dynamics of Compact Binary Systems at the Fourth Post-Newtonian Order

    Templates of coalescing compact binaries' gravitational waveform are used for the detection and precise determination of the physical parameters of gravitational waves by the current and next generations of interferometric detectors. In order to compute the waveform with high accuracy, the dynamics of compact binary systems should be known to the same precision. In this talk, I will address the question of the dynamics of non-spinning compact binary systems at the fourth post-Newtonian order in harmonic coordinates. I will present a method based on a Fokker action adapted to the specificities of the post-Newtonian formalism, including the so-called tail effects which appear for the first time in the conservative dynamics at 4PN. I will then derive the energy and periastron advance for circular orbits and show a full agreement with previous results from gravitational self-force calculations.

  • Tue
    21
    Mar
    2017
    4:00 pmLewis 101

    Sabrina Savage
    Science Research Office
    Marshall Space Flight Center

    Reconnecting with Solar Flares

    Because the Earth resides in the atmosphere of our nearest stellar neighbor, events occurring on the Sun's surface directly affect us by interfering with satellite operations and communications, astronaut safety, and in extreme circumstances, power grid stability. Solar flares, the most energetic events in our solar system, are a substantial source of hazardous space weather affecting our increasingly technology-dependent society. While flares have been observed using ground-based telescopes for over 150 years, modern space-bourne observatories have provided nearly continuous multi-wavelength flare coverage that cannot be obtained from the ground. We can now probe the origins and evolution of flares by tracking particle acceleration, changes in ionized plasma, and the reorganization of magnetic fields. I will walk through our current understanding of why flares occur, show several examples of these fantastic explosions, and describe the technology and instrumentation being developed at Marshall Space Flight Center to observe these phenomena.

  • Tue
    21
    Mar
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Sabrina Savage
    Science Research Office
    Marshall Space Flight Center

    Reconnecting with Solar Flares

    Because the Earth resides in the atmosphere of our nearest stellar neighbor, events occurring on the Sun's surface directly affect us by interfering with satellite operations and communications, astronaut safety, and in extreme circumstances, power grid stability. Solar flares, the most energetic events in our solar system, are a substantial source of hazardous space weather affecting our increasingly technology- dependent society. While flares have been observed using ground- based telescopes for over 150 years, modern space-bourne observatories have provided nearly continuous multi-wavelength flare coverage that cannot be obtained from the ground. We can now probe the origins and evolution of flares by tracking particle acceleration, changes in ionized plasma, and the reorganization of magnetic fields. I will walk through our current understanding of why flares occur, show several examples of these fantastic explosions, and describe the technology and instrumentation being developed at Marshall Space Flight Center to observe these phenomena.

    See this page for details.

  • Tue
    28
    Mar
    2017
    4:00 pmLewis 101

    Ulrich Sperhake
    Theoretical Astrophysics
    California Institute of Technology

    Searching for Smoking Gun Effects of Modified Gravity in Supernova Core Collapse

    Even though Einstein's theory of general relativity has been an incredibly successful theory and passed a plethora of tests ranging from light bending to the recent detection of gravitational waves, there are indications from theory, astrophysics and cosmology that modifications to the theory may ultimately be required. One of the most popular modifications applied to general relativity is the addition of a scalar field as an extra channel to mediate gravity. Through the introduction of additional degrees of freedom such scalar-tensor theories may explain some of the potentially troublesome phenomena in gravity while preserving compatibility with solar system and other tests. In this talk we explore the dynamics and gravitational wave emission of supernova core collapse in scalar tensor theory for the case of spherical symmetry. We analyse the resulting waveforms and explore under which conditions they may provide smoking gun signals detectable with present and future gravitational-wave detectors.

  • Tue
    04
    Apr
    2017
    4:00 pmLewis 101

    Michael Allshouse
    Department of Mechanical and Industrial Engineering
    Northeastern University

    Internal Wave Breaking and Boluses

    The shoaling of internal waves on a continental slope results in wave steepening and breaking that produces boluses, which are trapped regions of fluid that travel up the slope with the wave. Unlike a propagating solitary wave, these boluses transport material with the wave containing oxygen depleted water and induce rapid changes in temperature both of which have potential ramifications for marine biology. The dramatic difference between the fluid inside the bolus relative to the exterior may also impact local acoustic measurements of the sea floor. We extend a number of two-layer studies by investigating bolus generation and material transport in continuously stratified fluids. Laboratory experiments are conducted in a 4 m long tank and are complemented by 2-dimensional numerical simulations. The boundaries of the bolus are identified using a Lagrangian based coherent structure method relying on trajectory clustering. We use the structure identification to measure the properties of the bolus as a function of the pycnocline thickness and slope angle.

  • Sun
    09
    Apr
    2017
    8:15 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • April 9, Sunday, 8:15 - 10:30 PM

    We plan to observe  the Moon,  nebulae  and  star  clusters though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!
    Due to the buses we have moved from Friday to Sunday nights.
    See this page for the full schedule.

  • Tue
    11
    Apr
    2017
    4:00 pmLewis 101

    Wanwei Wu
    Department of Physics and Astronomy
    University of Mississippi

    The Muon g-2 Experiment at Fermilab

    The muon anomalous magnetic moment (g-2) has played an important role in constraining physics beyond the Standard Model for many years. The Fermilab Muon g-2 Experiment has a goal to measure it to unprecedented precision: 0.14 ppm, which will have a fourfold improvement compared to the BNL g-2 Experiment (0.54 ppm) as well as provide one of the most sensitive tests of the completeness of the Standard Model by comparing with the theory. The Fermilab g-2 Experiment is close to the end of installation and ready for the commissioning and physical running soon. In this talk, I will give an overview of the experiment and discuss the work involved by the OleMiss group.

  • Tue
    11
    Apr
    2017
    6:00 pmLusa Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Susana Martinez-Conde,
    Laboratory of Integrative Neuroscience,
    State University of New York — Downstate Medical Center

    Vision is All About Change

    Your eyes are the sharks of the human body: they never stop moving. In the past minute alone, your eyes made as many as 240 quick movements called “saccades” (French for “jolts”). A portion of our eye movements we do consciously, and are at least aware of on some level. But most of these tiny back-and-forths and ups-and-downs are unconscious and nearly imperceptible; someone staring directly at your eyes would miss most of them. Scientists long believed that we use two types of oculomotor behavior to sample the visual world, alternating between big saccades to scan our surroundings and tiny ones to fix our gaze on a location of interest. Explore, fixate, repeat, all day, every day. It seemed to make intuitive sense that we would have one brain system for exploring the environment and another for focusing on specific objects. But it turns out that exploration and gaze-fixation are not all that different processes in the brain. Instead, our eyes scan visual scenes with a same general strategy, whether the images are huge or tiny, or even when we try to fix our gaze. This insight may offer clues to understanding normal oculomotor function in the healthy brain, and oculomotor dysfunction in neurological disease.

    See this page for details.

  • Tue
    18
    Apr
    2017
    4:00 pmLewis 101

    Tanaz A. Mohayai
    Department of Physics
    Illinois Institute of Technology

    Measurements Of Beam Cooling In Muon Ionization Cooling Experiment

    The international Muon Ionization Cooling Experiment, MICE, is a high energy physics experiment located at Rutherford Appleton Laboratory in the U.K., and its aim is to demonstrate muon beam cooling for the first time. When muons are produced from pion decay, they occupy a large volume in the position-momentum phase space and the process of reducing their volume is known as beam cooling. Several beam cooling techniques exist, but the ionization cooling is the only technique fast enough to be used for muons within their short lifetime. Ionization cooling occurs when the beam loses momentum through energy loss, while traversing a material. In MICE, commonly used figures of merit for cooling are the beam emittance reduction, the phase-space volume reduction, and the phase-space density increase. Emittance is the measure of the size of the beam, and with a reduced beam emittance or phase-space volume, more muons can fit in a smaller aperture of a cost-effective accelerator. This may enable the construction of a future high-intensity muon accelerators, such as a Neutrino Factory or a Muon Collider. To demonstrate beam cooling, MICE makes use of two scintillating-fiber tracking detectors, immersed in the constant magnetic fields of the Spectrometer Solenoid modules. These trackers, one upstream and one downstream of the absorber reconstruct and measure the position and momentum coordinates of individual muons, and the absorber provides the ionization energy loss required for beam cooling. The choice of absorber material is dependent on the achievable energy loss, and the aim is to maximize beam cooling through energy loss while minimizing beam heating from multiple Coulomb scattering. In addition, given the precision with which MICE aims to demonstrate beam cooling, it is necessary to develop analysis tools that can work around any effects which may lead to inaccurate cooling measurements. Non-linear effects in beam optics is one example of such effects and it can result in apparent emittance growth or beam heating. The Kernel Density Estimation, KDE technique is an analysis tool which is insensitive to these non-linear effects and measures the muon beam phase-space density and volume. This talk will give an overview of the recent MICE results, the emittance measurement technique in the recent MICE data, and the novel application of the KDE technique in MICE.

  • Sat
    22
    Apr
    2017
    10:30 amUniversity Circle

    Join us for a celebration of science. Walk from Campus to Oxford square on April 22 to champion and support science.

    Science protects the health of our communities, the safety of our families, the education of our children, the foundation of our economy and jobs, and the future we all want to live in and preserve for coming generations. Science is a tool of discovery that allows us to constantly expand and revise our knowledge of the universe. In doing so, science serves the interests of all humans. Science education teaches children and adults to think critically, ask questions, and evaluate truth based on the weight of evidence. Science promotes diversity and inclusion in science to build robust and resilient communities for the benefit of all people. Science makes our democracy stronger.

    On April 22, scientists and supporters of science will march in cities and towns across the world to reaffirm these core values.

    Please stand up for science and join your fellow Ole Miss scientists in a celebration of science by walking from campus to Oxford square. This is a strictly non-political, non-partisan event. We value inclusion, diversity, equity, and access to everybody. We aim for a diverse group of participants, including first-time marchers. Families with young children are welcome.

    We will assembly on the steps of the Lyceum (University Circle) at 10:30 am and start walking at 11:00am. The planned route (about 1 mile) will take us through the Grove, University Avenue and South Lamar. We will end the march at Oxford Square.

    Please show your support for science as a vital feature of a working democracy, spurring innovation, critical thinking, increased understanding, and better, healthier lives for all people. Follow us on Twitter and Facebook (event).

  • Tue
    25
    Apr
    2017
    4:00 pmLewis 101

    Guido Mueller
    Department of Physics
    University of Florida

    TBA

  • Tue
    02
    May
    2017
    4:00 pmLewis Hall

    Bevin Etienne
    McIntire School of Commerce
    University of Virginia

    The Role of Microgrids and Community Choice Aggregation in Building a Sustainable and Resilient Energy System

    Energy plays a role in every facet of our lives - from food production to clothing and shelter, to the water we drink and the air we breathe and by great extent our ability to do the work we enjoy. With that being said, the energy sector, globally, is plagued with many challenges. For example, the electric grid and most of the energy infrastructure in the US was constructed in the 1950s and 1960s with a 50-year life expectancy1 which signifies the US is due for an overhauling of the system. This does not account for the fact that the energy system of the 1950s and 1960s was not engineered to meet today's energy demands and capability to withstand severe weather related events – in 2012, Super storm Sandy demonstrated our energy system vulnerability to severe weather. All of this suggests that the time is at hand for significant investment in maintaining, upgrading and rebuilding the electric energy infrastructure. Recently conducted research suggests that the replacement value of the U.S. electric grid is $4.8 trillion2.

    This discussion will focus on the use of Microgrids and Community Choice Aggregation (CCA) in addressing the impending energy crisis and assess the social, economic and environmental benefits of employing such an approach to tackling the current energy challenge. Beyond the US, microgrids and CCA offer the opportunity for developing nations to leapfrog the centralized energy infrastructure and provide a more sustainable
    and secure energy system for the 21st century.


    1The American Society of Civil Engineers (ASCE) 2017 Infrastructure Report Card
    2Tsvetana Paraskova, OilPrice.com

  • Tue
    09
    May
    2017
    11:15 amLewis Hall 101

    The 2017 induction ceremony for the National Physics Honors Society, ΣΠΣ will take place on May 9 at 11:15 AM in room 101 in Lewis Hall.

  • Fri
    30
    Jun
    2017
    8:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • June 30, Friday, 8:30 - 10:00 PM

    We plan to observe  the Moon, Jupiter and Saturn. though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!

    See this page for the full schedule.

  • Mon
    17
    Jul
    2017
    Thu
    20
    Jul
    2017
    9:00 amRoom 109 Lewis Hall

    The 3rd Annual Belle II Summer School will be held at the University of Mississippi — Monday July 17, 2017 until Thursday July 20, 2017.

    Agenda Topics include:
    Computing, Analysis setup, KLM particle ID, TOP particle ID
    Nanobeams, Vertexing, BASF2, Early physics, BEAST, Reconstruction Code
    Drift Chamber, ARICH particle ID, Event Display

    The Registration will start in room 104 of Lewis Hall at 8:30 AM Monday morning. The meeting will start in room 109 of Lewis Hall at 9:00 AM Monday morning. Lectures will be in room 109 Lewis Hall and the Breakout rooms will be in rooms 109 and 228 Lewis Hall.

    Please see http://www.phy.olemiss.edu/b2ss2017/ for details

  • Fri
    28
    Jul
    2017
    8:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • July 28, Friday, 8:30 - 10:00 PM

    We plan to observe  the Moon, Jupiter and Saturn. though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!

    See this page for the full schedule.

  • Mon
    21
    Aug
    2017
    12:00 pmQuad between Lewis Hall, the Library and the Lyceum

    On Aug. 21, Monday, a total solar eclipse swipes through the U.S., a once-in-a-lifetime event. It is best viewed in a narrow band that crosses Nashville, TN.

    It can be seen in Oxford, MS, as a partial solar eclipse, which is still a rare occurrence. While not a total eclipse the Sun will be over 90% covered so it will still be quite impressive. The Department of Physics and Astronomy will organize a viewing 12:00 noon - 3:00 PM. The maximum coverage is at 1:24 PM.

    The viewing is free, all are welcome. (In case clouds cover the Sun, there will be nothing to see.)

    Note: Never look into the eclipsed Sun without a proper solar filter, it is dangerous!!

     

  • Tue
    29
    Aug
    2017
    4:00 pmLewis Hall 101

    Mike Reep and Scott Watkins
    Department of Physics and Astronomy
    University of Mississippi

    Machine Shop Physics

    Experimental physics depends on instrumentation made in the University of Mississippi's Physics machine shop. Instruments made for Acoustics,
    Atmospheric physics, Condensed Matter physics, and Particle physics will be shown.

  • Tue
    05
    Sep
    2017
    4:00 pmLewis 101

    Vahid Naderyan
    Department of Physics and Astronomy
    University of Mississippi

    MEMS Microphones

    MEMS (Micro-Electro-Mechanical Systems) microphones are acoustic sensors which translate sound waves to an electrical signal. Recent developments in MEMS technology have led to the development of very small size and high-performance microphones. Silicon fabrication creates the MEMS elements with the geometries of the order of microns. Due to their small size and high performance, MEMS microphones are used in mobile phones, hearing aids, “Internet of Things” devices, small electronic devices, etc. In this talk, I will explain the basic principles of the capacitive MEMS microphones and will talk about the Acoustical, Mechanical, and Electrical domains in a MEMS microphone and their connections.

  • Tue
    19
    Sep
    2017
    4:00 pmLewis 101

    Ron Miles
    Department of Mechanical Engineering
    State University New York — Binghamton

    The Nanophone: Sensing Sound with Nanoscale Spider Silk

    Hundreds of millions of years of evolution resulted in hair-based flow sensors in terrestrial arthropods that stand out among the most sensitive biological sensors known. These tiny sensory hairs can move with a velocity close to that of the surrounding air at frequencies near their mechanical resonance, in spite of the low viscosity and low density of air. No man-made technology to date demonstrates comparable efficiency. Here we show that nanodimensional spider silk captures fluctuating airflow with maximum physical efficiency (Vsilk/Vair ≈1) from 1Hz to 50kHz, providing an unparalleled means for miniaturized flow sensing. Our mathematical model shows excellent agreement with experimental results for silk with various diameters: 500nm, 1.6µm, 3µm. When a fiber is sufficiently thin, it can move with the medium flow perfectly due to the domination of forces applied to it by the medium over those associated with its mechanical properties. By modifying a spider silk to be conductive and transducing its motion using electromagnetic induction, we demonstrate a miniature, directional, broadband, passive, low cost approach to detect airflow with full fidelity over a frequency bandwidth that easily spans the full range of human hearing, as well as other mammals, birds, amphibians, and reptiles.

  • Tue
    19
    Sep
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Ronald Miles
    Department of Mechanical Engineering
    State University New York — Binghamton

    Biomimetic Acoustic Sensors for Hearing Aids

    Current hearing aids typically use a pair of miniature microphones in order to achieve directional acoustic sensing. Better hearing aids can be designed by examining how the hearing organs of very small animals such as insects and spiders enable these creatures to detect and localize sound. We have studied the hearing in mosquitoes, flies, crickets, midges, caterpillars, and spiders to explore remarkable ways these animals sense sound. This talk will describe our discovery of the amazing directional ears of a special fly, Ormia ochracea, which is able to localize sound better than humans can even though its ears fit in a space only 1 mm across. Our biomimetic microphones based on this discovery show better performance than existing hearing aid microphones. We have also recently discovered new ways to sense sound based on the use of nanoscale fibers such as insect hairs or spider silk. This has resulted in a directional microphone that has ideal flat frequency response from 1 Hz to 50 kHz, far beyond the range of human hearing. There remains much more to learn from nature to create technology to improve hearing.

    See this page for details.

  • Tue
    26
    Sep
    2017
    4:00 pmLewis 101

    Farhad Farzbod
    Department of Mechanical Engineering
    University of Mississippi

    Vibrations: from Periodic Structures to the Human Face

    This talk covers four different and yet connected subjects; Resonant Ultrasound Spectroscopy (RUS), vibration analysis of periodic structures,
    and using facial vibrations in wearable computers. RUS is a technique to characterize the elastic and anelastic properties of materials. It is based on the measurements of the vibration eigenmodes of a sample with simple geometry such as a parallelepiped. In Laser RUS, the excitation part is done by a pulsed laser, generating thermoelastically excited ultrasonic pulse. In the detection side, a photorefractive interferometer is used to detect ultrasound. Measured eigenmodes along with eigenfrequencies reveal much information with regard to micro-structural state of the sample material. Novel techniques/problems in laser RUS is discussed in this section. In the second part, periodic structures are discussed. In periodic lattice structures, analysis of wave propagation to uncover dispersion relationships can be greatly simplified by invoking the Floquet-Bloch theorem. The accompanying Bloch formalism, which was first introduced for the study of quantum mechanics and has been borrowed in structural analysis, allows a system's degrees of freedom to be reduced to a small subset contained in a single unit cell. When this is combined with the finite element method, the result is a powerful framework for analyzing wave propagation and dispersion in complex media. In this section, among other things, the manner in which damping affects dispersion is talked about. In the next part, I talk about reciprocity in acoustics and how to break it; one way to break time reversal symmetry is to have a moving wave propagation medium. If the acoustic wave vector and the moving fluid velocity are collinear, we can use the wave vector shift caused by the fluid flow to break reciprocity. An alternative approach we have taken, is to use a fluid velocity field which enters the differential equation of the system as a cross product term with the wave vector. In the final part, bone conduction hearing is discussed; how it helps hearing and how it can be utilized for better communications in wearable technologies.

  • Sun
    01
    Oct
    2017
    7:00 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • October 1, 2017  7:00 - 9:00 PM

    We plan to observe  the Moon and Saturn. though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!

    See this page for the full schedule.

  • Tue
    03
    Oct
    2017
    4:00 pmLewis 101

    John Thompson
    Department of Physics and Astronomy
    University of Maine

    Investigating Student Understanding at the Physics-Mathematics Interface

    Because learning physics concepts often requires the ability to construct, interpret, and manipulate mathematical representations and formalism
    (e.g., equations, graphs, and diagrams), researchers in physics education and mathematics education have been examining how students navigate
    this interface between mathematics and physics. Our own research into student conceptual understanding of physics has led us to investigate how
    students use and reason about mathematics, especially calculus, to solve physics problems in several upper-division physics domains. Examples
    coming from thermal and statistical physics as well as from vector calculus as used in electromagnetism will be given. Instructional materials
    development and implementation will be discussed.

  • Tue
    10
    Oct
    2017
    4:00 pmLewis 101

    Alex Yakovlev
    Department of Electrical Engineering
    University of Mississippi

    Recent Developments on Graphene and Graphene Periodic Surfaces at Microwave and Terahertz Frequencies

    Graphene, the first 2D material to be practically realized, has attracted great interest in the last decade. The fact that electrons in graphene behave as massless Dirac fermions leads to a variety of anomalous properties, such as charge carriers with ultra-high-mobility and long mean-free paths. Graphene's electrical properties are often represented by a local complex surface conductivity given by the Kubo formula. Since its surface conductivity leads to attractive surface plasmon properties, graphene has become a good candidate for plasmonic applications, especially in the terahertz regime.

    In this talk we will briefly discuss electrical, thermal, and mechanical properties of graphene, and will focus on the interaction of electromagnetic waves with graphene and graphene periodic surfaces at microwave and terahertz frequencies. Specifically, we will discuss the enhanced transmission with a graphene-dielectric stack, dual capacitive/inductive nature of graphene periodic surfaces, high-impedance surfaces with graphene patches, excitation of surface plasmon polaritons on graphene, planar hyperlens based on a modulated graphene, subwavelength imaging with graphene loaded wire media, and cloaking with graphene for antenna applications.

  • Tue
    17
    Oct
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Carolyn Freiwald,
    Department of Sociology and Anthropology,
    University of Mississippi

    This is Your Life in a Tooth

    You might be surprised to learn that a single tooth contains a record of your life... from the types of food that you ate, to where you lived, to how healthy you were as a child. Vegetarians and BBQ lovers have different chemical markers, and so do people with jobs such as blacksmiths. It is "you are what you eat" at the molecular level. Archaeologists use chemistry to reconstruct the past, learning what ancient people ate and drank, and discovering just how mobile they were. Migrants made up part of cities such as Cahokia across North America 1000 years ago, and formed part of the social fabric in cities throughout Mexico, Latin America, ancient Rome and across the world. Immigration is not a new phenomenon and likely not a new debate. Bone chemistry also has important applications in forensic cases, including identifying missing persons. We'll look at how science works to help us solve both ancient and modern mysteries.

    See this page for details.

  • Fri
    20
    Oct
    2017
    4:00 pmLewis 101

    Brian Daly
    Department of Physics and Astronomy
    Vassar College

    Picosecond Ultrasonics: Nanoscale Imaging and GHz Surface Acoustic Wave Studies

    Ultrafast lasers produce pulses of light that are less than 1 ps in duration, and can be used to generate and detect extremely high frequency ultrasound in the range of about 100 GHz. This technique can be applied to semiconductor metrology (nanometer scale thickness measurements, mechanical properties of thin films, imaging of sub-surface nanostructures) but also provides a window to the fundamental behavior of long-wavelength acoustic phonons that have a significant impact on thermal transport at the nanoscale. In this talk I will review the picosecond ultrasonic measurement technique and discuss recent work to advance nanoscale imaging and the study of surface acoustic waves.

  • Fri
    27
    Oct
    2017
    7:00 pmLewis Hall

    Frights, food and fun are the order of the evening when the University of Mississippi Department of Physics and Astronomy presents "Spooky Physics Demonstrations" from 7 to 9 p.m. Friday (Oct. 28) in Lewis Hall.

    The program will include a stage show at 8 p.m. Hands-on activities for the public through the evening include freezing objects in liquid nitrogen (at minus 320 degrees), generating sound waves with Bunsen burners and tubes, and levitating magnets with superconductors. Other fun presentations include optical illusions with mirrors, a Van de Graaff generator (a literally “hair-raising” electrical device), a bed of nails and other contraptions.

    Physics department personnel also will prepare ice cream with liquid nitrogen and award prizes for the most original, scariest and cutest costumes to kids aged 12 and under.

  • Sun
    29
    Oct
    2017
    6:30 pmKennon Observatory

    We are offering astronomy open houses and viewings with our telescopes:

    • October 29, 2017  6:30 - 9:00 PM

    We plan to observe  the Moon and other interesting objects. though our telescopes.  All these events are weather permitting. Admission is free.
    Children are welcome!

    See this page for the full schedule.

  • Tue
    31
    Oct
    2017
    4:00 pmLewis 101

    Shaon Ghosh
    Department of Physics
    University of Wisconsin - Milwaukee

    From the Ashes of a Pair of Neutron Stars: The Tale of a Kilonova

    The observation of the binary neutron star coalescence and the resulting electromagnetic counterpart by LIGO & Virgo and the various observing partners around the world has been one of the most amazing discoveries in physics and astronomy in recent times. The multitude of results that were obtained from this discovery, each in their own rights are fascinating. In this talk, I will attempt to condense these results and put them in the context of the efforts that have been carried out for many decades. I will first give a very short history of the subject, then I will talk about the description of the model of the physical process that we thought were responsible for the observed phenomenon. Next, I will talk about the proposed test to verify our model, and how we conducted them. Finally, I will summarize the important results of the multi-messenger observation.

  • Tue
    07
    Nov
    2017
    4:00 pmLewis 101

    Jake Bennett
    Department of Physics
    Carnegie Mellon University

    Prospects for Hadron Spectroscopy at Belle II

    The Belle II experiment, currently under construction at the KEK laboratory in Tsukuba, Japan, is the next generation of the highly successful B-factories. A substantial upgrade of both the Belle detector and the KEKB accelerator represent an essentially new experiment. Commissioning of the new SuperKEKB accelerator will start at the end of 2017. Physics running is planned to start in 2018 with a goal of collecting 50 times more data than the first generation B-factories. Belle II is uniquely positioned to make detailed studies of "exotic" hadron states, the so-called XYZ states, that provide the first possibility to explore long-conjectured, nonstandard quarkonium-like states. This talk will give an overview of the detector and accelerator upgrades and describe some of the capabilities of Belle II to explore both conventional and exotic bottomonium and charmonium physics.

  • Fri
    10
    Nov
    2017
    4:00 pmLewis 101

    Chris Moore
    Departamento de Fisica
    Instituto Superior Técnico — CENTRA, Portugal

    The Era of Gravitational Wave Astronomy

    The era of gravitational wave astronomy has begun. The LIGO and Virgo observatories are already revealing the properties of neutron star and stellar mass black hole coalescences. However, many more discoveries await. In the coming years we expect to observe gravitational radiation across a frequency spectrum spanning >10 orders of magnitude, generated by a diverse array of sources from white dwarf stars to supermassive black holes. I will discuss what I consider to be some of the most exciting prospects, and identify several key challenges that must be addressed for these discoveries to be fully utilised in the fields of astronomy, fundamental physics, and cosmology.

  • Tue
    14
    Nov
    2017
    4:00 pmLewis 101

    William E. East
    Perimeter Institute for Theoretical Physics, Canada

    Uncovering the Dynamics of Spacetime

    With the ground-breaking gravitational wave detections from LIGO/VIRGO, we have entered the era where we can actually observe the action of strongly curved spacetime originally predicted by Einstein. Going hand in hand with this, there has been a renaissance in the theoretical and computational tools we use to understand and interpret the dynamics of gravity and matter in this regime. I will describe some of the rich behavior exhibited by sources of gravitational waves such as the mergers of black holes and neutron stars. I will also discuss some of the open questions, and what these events could teach us, not only about the extremes of gravity, but about the behavior of matter at nuclear densities, the solution of astrophysical mysteries, and even the existence of new particles.

  • Tue
    14
    Nov
    2017
    6:00 pmLuca Bakery and Cafe, 1120-1122 North Lamar Blvd Oxford, Mississippi

    Dr. Jason Hoeksema,
    Department of Biology,
    University of Mississippi

    Wild Mushrooms: Ecology, Edibility, and More

    What is a mushroom? What is it's natural function for fungi? Which ones are delicious and which ones will make you ill or worse? We will answer all these questions. We'll start with a discussion of fungal ecology, especially focusing on how fungi obtain food, and the really interesting ways that fungi can change the ecology of plants and nutrient cycling. We'll talk about the role of mushrooms in the life cycles of fungi. Finally, we'll discuss strategies for finding and safely enjoying wild mushrooms in northern Mississippi.

    See this page for details.

  • Thu
    16
    Nov
    2017
    2:45 pmLewis 101

    Leo Stein
    Walter Burke Institute for Theoretical Physics
    California Institute of Technology

    Probing Strong-Field Gravity: Black Holes and Mergers in General Relativity and Beyond

    General relativity—Einstein's theory of gravitation—has been studied for more than 100 years. Over the past century, we have learned that the theory agrees with all available experimental and observational tests. At the same time we know that the theory is incomplete, as it leads to inconsistencies when coupled with quantum mechanics.

    The strong-field regime is our best hope to study GR, both observationally and theoretically, and thus understand how to correct its shortcoming. In this talk, I will discuss investigations in the strong field, including black holes and neutron stars, in GR and theories beyond GR. The main focus will be predicting gravitational waves from merging black holes beyond GR. These predictions will allow for the most rigorous testing of general relativity, using LIGO, in the dynamical strong-field regime.

  • Thu
    16
    Nov
    2017
    4:00 pmLewis 101

    Graduate Students
    Department of Physics and Astronomy
    University of Mississippi

    Graduate Student Research Symposium