Events at Physics |
Events During the Week of October 25th through November 1st, 2009
Monday, October 26th, 2009
- Plasma Physics (Physics/ECE/NE 922) Seminar
- Electron Thermal Transport within Magnetic Islands in the RFP" and "Internal Electron Transport Barrier Due to Neoclassical Ambipolarity in the HSX Stellarator
- Time: 12:05 pm
- Place: 4274 Chamberlin Hall
- Speaker: Hillary Stephens and Jeremy Lore, University of Wisconsin-Madison
Tuesday, October 27th, 2009
- Chaos & Complex Systems Seminar
- Title to be announced
- Time: 12:05 pm
- Place: 4274 Chamberlin (Refreshments will be served)
- Speaker: Martin and Betsy David, Economics
- String Theory Seminar
- New SUSY Breaking Backgrounds and Holographic Gauge Mediationy
- Time: 3:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Yoske Sumitomo, UW-Madison
- Host: Gary Shiu
- String Theory Seminar
- New SUSY Breaking Backgrounds and Holographic Gauge Mediationy
- Time: 3:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Yoske Sumitomo, UW-Madison
- Host: Gary Shiu
- Astronomy Colloquium
- The Dark Lives of Galaxies: Investigating Their Seedy Baryonic Underbellies with Ultraviolet Spectroscopy
- Time: 3:30 pm - 5:00 pm
- Place: 3425 Sterling Hall
- Speaker: Todd Tripp, University of MA- Amhearst
- Abstract: t has long been recognized that stars and planets and such account
for a tiny fraction of the ordinary matter in the universe, and astronomers have been intensively searching for the missing baryons for more than a decade, with some palpable (but frustratingly slow) progress. It is likely that the missing baryons are hiding out in very low-density plasmas in galaxy halos and the intergalactic medium.<br>
It is difficult to detect emission from those shady plasmas; ultraviolet and X-ray absorption spectroscopy will provide the main tools for surveillance of most of the baryons for the foreseeable future. UV spectroscopy provides a particularly potent combination of high spectral resolution (R = 20,000 to >>>100,000), rich diagnostics of physical conditions, access to a large number of metals, and many bright background continuum sources. Detection of the missing baryons is a consistency check of CDM cosmology and how large-scale structures grow, but it is also much more. Galaxy-halo-IGM interactions via inflows and outflows must play a major role in galaxy evolution, but again the baryons in the flows are dark, and the flow physics are poorly understood due to missing observational constraints, e.g., of cooling gas at T > 100,000 K.
With the recent deployment of the UV Cosmic Origins Spectrograph on HST, we are on the verge of a major observational bust of the dark baryons. Using data from UV spectrographs on HST and FUSE, this talk will demonstrate the power of the technique and anticipate upcoming breakthroughs. Examples will include insights on galaxy transformation via ram-pressure stripping (or something) and gas consumption, dusty and multiphase galactic fountains, and a new signature of galactic flows. Within 5 years, COS will provide strong statistical constraints on the quantity and physical state of baryons in halos and the IGM. Wednesday, October 28th, 2009
- No events scheduled
Thursday, October 29th, 2009
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- The low-down on Ultrahigh Energy Cosmic Rays: experimental results and theoretical puzzles
- Time: 4:00 pm
- Place: 4274 Chamberlin
- Speaker: Glennys Farrar, New York University
- Abstract: Observed properties of UHECR showers are difficult to reconcile with simulated showers and arrival direction information, and no choice of composition seems compatible with all observations. At the moment, one or more improbable or very improbable statistical fluctuations, or a new physics threshold at about 100 TeV, seem to be the only viable explanations. I will also describe new, much better constraints on the Galactic Magnetic Field. The proposal that a large fraction of UHECRs may come from Centaurus A -- which, at about 3.5 Mpc is the closest plausible source -- can be excluded, unless extragalactic magnetic fields are much larger than generally thought.
- Host: Stefan Westerhoff
- Introductory Graduate Seminar
- String Theory
- Time: 5:30 pm
- Place: 2223 Chamberlin Hall
- Speaker: Hashimoto, Shiu, University of Wisconsin Department of Physics
Friday, October 30th, 2009
- Theory/Phenomenology Seminar
- Hidden Charged Dark Matter
- Time: 2:30 pm - 3:30 pm
- Place: 5280 Chamberlin Hall
- Speaker: Haibo Yu, University of California-Irvine
- Host: S. Spinner
- Physics Department Colloquium
- 50 Years of Fusion Research
- Time: 4:00 pm
- Place: 2241 Chamberlin Hall (coffee at 3:30 pm)
- Speaker: Dale M. Meade, Fusion Innovation Research and Energy, Princeton, NJ
- Abstract: Fusion energy research began in the early 1950s as scientists worked to harness the awesome power of the atom for peaceful purposes. There was early optimism for a quick solution for fusion energy as there had been for fission. However, this was soon tempered by reality as the difficulty of producing and confining fusion fuel at temperatures of 100 million degC in the laboratory was appreciated. Fusion research has followed two main paths - inertial confinement fusion and magnetic confinement fusion. Over the past 50 years, there has been remarkable progress with both approaches, and now each has a solid technical foundation that has led to the construction of major facilities that are aimed at demonstrating fusion energy producing plasmas.
- Host: Forest