Events at Physics |
Events During the Week of October 29th through November 5th, 2017
Monday, October 30th, 2017
- Plasma Physics (Physics/ECE/NE 922) Seminar
- Turbulence Driven by Compressional Magnetic Fluctuations in Laboratory, Space, and Pair Plasmas
- Time: 12:00 pm - 1:00 pm
- Place: Chamberlin 2241
- Speaker: Dr. M. J. Pueschel, Institute for Fusion Studies, University of Texas at Austin
- Abstract: Recent experiments conducted at the Large Plasma Device reveal strong compressional, or parallel, magnetic fluctuations in the region of large density and temperature gradients. Using state-of-the-art gyrokinetic turbulence modeling, we show that the driver of these fluctuations is a new turbulence regime, where plasma instability occurs due to a coupling of the ExB and grad B drifts. Implications of this process include the ability of this instability to allow current sheet relaxation, thus enhancing reconnection rates in solar scenarios, boosting coronal heating rates. Furthermore, the instability is even found to occur in matter-antimatter pair plasmas in homogeneous guide fields, a class of plasmas previously thought to be completely stable to pressure gradients. We discuss consequences for magnetic-confinement, laser-induced, and astrophysical pair plasmas.
- Host: Paul Terry
- Council Meeting
- Time: 4:00 pm
- Place: 2314 Chamberlin Hall
Tuesday, October 31st, 2017
- Chaos & Complex Systems Seminar
- Partisan redistricting in Wisconsin
- Time: 12:05 pm - 1:00 pm
- Place: 4274 Chamberlin (refreshments will be served)
- Speaker: David Canon, UW Department of Political Science
- Abstract: Professor David Canon will discuss the potential landmark Supreme Court case, Gill v. Whitford, concerning partisan redistricting. Canon will provide some background on the law and the basic principles of redistricting, explore the history of partisan redistricting and then discuss the Wisconsin case. He will speculate about the likely outcome, with a focus on the role of Justice Kennedy and the new measure of partisan bias (the “efficiency gap”). Canon will conclude by talking about possible reforms, with a focus on Iowa’s nonpartisan model of redistricting.
- Host: Clint Sprott
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Traces in polar ice: neutrinos, dust, life and a million-year core
- Time: 4:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Ryan Bay, UC Berkeley
- Host: Halzen
Wednesday, November 1st, 2017
- Department Meeting
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
- Science on Tap
- Did the Universe pour us a stout?
- Time: 7:00 pm - 9:00 pm
- Place: Nomad World Pub 418 E. Wilson St.
- Speaker: K. Palladino, UW- Madison
- Abstract: Dark matter, dark beer, dark times (Happy Halloween!). The day before we gather is not only All Hallows’ Eve, it’s also #DarkMatterDay. But what is dark matter exactly? Well, it makes up five times more of the matter in the universe than all the stars, planets, galaxies and other “regular matter” we are used to, but scientists know more about what dark matter isn’t than what it is. UW–Madison Physics Professor Kim Palladino plans to take us on a journey of dark matter, which she says is gravitationally important for the formation of galaxies and the development of the universe. So, let Nomad – and the universe – pour you a stout and sit back as she explains how scientists are trying to uncover more about dark matter, including by placing large detectors deep underground. Completely free and open to all ages. Parking is available across from the bar in the Hancock Street lot after 6 p.m. Served by buses: 3, 4, 10, 38, 56, 57
Thursday, November 2nd, 2017
- Wisconsin Science Festival
- IceCube at Wisconsin Science Festival
- Time: 9:00 am
- Place: Discovery Building
- Speaker: IceCube faculty and staff
- Abstract: Come learn more about IceCube at the Wisconsin Science Festival. We will be at the Discovery Building from Nov 2nd and Nov 3rd, 9am-2pm and Nov 4th from 10am-3pm! We will have interactive activities for kids and adults, including our IceCube LED display.
- R. G. Herb Condensed Matter Seminar
- Design and Synthesis of 1D and 2D Nanomaterials Away from Equilibrium
- Time: 10:00 am
- Place: Chamberlin 5310
- Speaker: Xudong Wang, UW-Madison (Materials Science and Engineering)
- Abstract: Morphology is one essential element that gives rise to extraordinary physical, chemical, and mechanical properties in nanomaterials. Precise morphology control of nanomaterials is a notorious task, which heavily relies on fundamental understanding of the governing mechanisms and kinetics at the nanoscale. In this talk, I will present our three recent discoveries of the growth kinetics in 1D and 2D nanomaterial evolution. Firstly, the surface-reaction-limited pulsed chemical vapor deposition (SPCVD) technique will be discussed. The SPCVD technique effectively decouples the crystal growth from precursor vapor concentration, thus makes the conform growth of dense NW arrays inside highly-confined submicron-sized spaces possible. The evolution of NRs was found to be a manifestation of the Ostwald-Lussac Law. SPCVD opens a new route toward the design and creation of complex 3D hierarchical nanostructures, which can advantageously impact the devices performance of solar energy harvesting. Secondly, I will present our discovery of the wedding cake growth mechanism in the formation of 1D and 2D ZnO nanostructures. Within a narrow kinetic window, the surfaces of the 1D and 2D structures were covered with a unique concentric terrace feature, different from the screw-dislocation features. An interesting 1D to 2D morphology transition was found during the wedding cake growth, when the adatoms overcome the Ehrlich-Schwoebel (ES) barrier. At last, I will present a new ionic layer epitaxy (ILE) technique that uses surfactant monolayers to serve as soft templates guiding the nucleation and growth of 2D nanomaterials in large area beyond the limitation of van der Waals solids. One- to two-nm-thick, single-crystalline free-standing ZnO nanosheets with sizes up to tens of micrometers were synthesized at the water-air interface. ILE of other metals and oxides have also been proved to be successful.
- Host: Alex Levchenko
- Atomic Physics Seminar
- The magnetic interstellar medium: cosmological and astrophysical perspectives
- Time: 3:30 pm - 5:00 pm
- Place: 4421 Sterling Hall, Coffee and cookies 3:30 pm, Talk begins at 3:45 pm
- Speaker: Susan Clark, Institute for Advanced Study
- Abstract: The interstellar medium (ISM) is multi-phase, turbulent, and magnetic. This makes the ISM an ideal laboratory for studying the multi-scale physics of star formation and galactic evolution. This unfortunately also makes the ISM a formidable foreground for cosmology experiments, such as the search for inflationary gravitational wave B-mode polarization in the cosmic microwave background. I will discuss recent work on magnetic fields in the diffuse ISM, with a particular focus on insights from high-dynamic range observations of neutral hydrogen and polarized dust emission. Novel tools for quantifying the morphology of interstellar material are enabling new probes of the ambient magnetic field structure, and thus a better characterization of polarized cosmological foregrounds. The hunt for primordial signals is now inextricably linked to our understanding of the magnetic ISM.
- Host: Prof Alexander Lazarian
Friday, November 3rd, 2017
- Physics Department Colloquium
- Unlocking the mysteries of the Universe with the CMS experiment at the Large Hadron Collider
- Time: 3:30 pm
- Place: 2241 Chamberlin Hall
- Speaker: Tulika Bose, Boston University
- Abstract: The discovery of the Higgs Boson at the Large Hadron Collider (LHC) in 2012 was a ground-breaking event in particle physics history. The LHC has restarted recently at an unprecedented center of mass energy of about 13 TeV and the data collected by the CMS experiment is expected to help fully understand the nature of electroweak symmetry breaking and potentially discover new physics. In this talk, I will review recent results from the CMS experiment with special focus on searches for physics beyond the Standard Model.
- Host: Sridhara Dasu
- Graduate School Admissions Q&A I: Meeting with an Admissions Committee Member
- Time: 5:00 pm - 7:00 pm
- Place: 2223 Chamberlin
- Abstract: Anyone interested in learning more about graduate school is welcome to attend a Q&A panel with admissions committee member Stanislav Boldyrev. This will be an opportunity for undergrads to ask questions about applying to graduate school and to learn about what an admissions committee looks for in an applicant.
This event is open to all undergraduates, and anyone interested is encouraged to attend.
- Host: Women and Gender Minorities in Physics