University of Wyoming Physics & Astronomy Colloquium Series

Fridays -- 4:10 PM -- Prowse Room 234

Pre-Colloquium tea served at 3:45 in the Prowse Room

Fall 2015 & Spring 2016 Schedule

August 7 Supermassive Black Holes and their Host Dark Matter Halos
Suchetana Chatterjee (Presidency University)

Through a plethora of observational results we now know that there is a supermassive black hole (SMBH) at the center of every galaxy in the Universe. A fraction of these harbor an active accretion disc, and are known as active galactic nuclei (AGN). Thus in the paradigm of structure formation we would like to address the question of relating SMBH to their host dark matter halos. Observationally by studying the spatial clustering of SMBH or AGN we can infer information about their dark matter hosts. AGN clustering can be characterized within a powerful theoretical framework known as the Halo Occupation Distribution (HOD). In this talk, I shall discuss HOD modeling of AGN using a fully cosmological simulation and show that the underlying theoretical model fits the two-point correlation function (2PCF) of different types of AGN. This provides us an evolutionary picture of AGN along with dark matter halos over cosmic time. In the latter half of the talk I shall provide some limitations of the 2PCF fitting method and provide alternative ways to measure the HOD of AGN while trying to address some fundamental questions in AGN physics from a cosmological point-of-view.

September 4 Mapping Galactic Dust in 3 Dimensions with Pan-STARRS1 and 2MASS
Douglas Finkbeiner (Harvard University)

2D emission-based maps have been used for decades to estimate the reddening and emission from interstellar dust, with applications from CMB foregrounds to surveys of large-scale structure. For studies within the Milky Way, however, the third dimension is required. I will present our work on a 3D dust map based on Pan-STARRS1 and 2MASS over 3/4 of the sky (, assess its significance compared to other dust maps, and say how we plan to approach the next step: R_V.

September 11 Infrared solar physics, a new era?
Philip Judge (UCAR)

I will discuss some old but fundamental problems in solar physics that can be boiled down to the deceptively simple question: "What causes the global solar magnetic field to flow and ebb, changing sign every 11 years?" I will argue that we are on the verge of some major advances using infrared technology. I will review a joint campaign to observe the infrared corona from the ground in Wyoming and from the NCAR GV aircraft during the August 21 2017 total eclipse, which passes over Wyoming. These new observations should pave the way towards a new understanding with the NSF's new flagship solar observatory, the 4 meter Daniel K. Inouye solar telescope (DKIST), scheduled for operations in 2019. These collaborations include U. Wyoming, NRL, SAO, NCAR and U. Torino. They include opportunities for undergraduate training.

September 18 New ideas in protoplanetary disk evolution
Philip Armitage (CU Boulder)

Protoplanetary disks are often assumed to evolve due to turbulent mixing of angular momentum, in the same way as accretion disks around black holes and compact objects. In the course of trying to model disk turbulence from first principles, however, we and other groups have found evidence that different processes may dominate disk evolution. Magnetized disk winds, and a form of internal magnetic braking driven by the Hall effect, may largely determine how disks evolve. I will discuss these new ideas for protoplanetary disk evolution, how they may be tested with sub-mm observations, and speculate on possible implications for planet formation.

September 25 The Puzzle of Anolamous Isotope Effect in High and Low Tc Superconductors
Prof. Guang-Lin Zhao (Southern University, Baton Rouge)

Superconductors have zero electrical resistance and expulsion of magnetic fields below a critical temperature Tc. They can carry electric current without any energy loss and have many applications. However, understanding superconductivity is a great challenge. Especially, anomalously small isotope effect in some high Tc superconductors such as YBa2Cu3O7 (YBCO) created a great challenge for understanding. TO solve the puzzle, a new methodology is implemented by integrating first-principles calculations of electronics structures of the materials into the theory of many-body physics for superconductivity. The aim is to seek a unified methodology to study the electronic and superconducting properties of the materials. It is demonstrated from first-principles that the extended saddle point singularities in the electronic structure of YBCO strongly correlate with the anomalous isotope effect in the superconductor. Some guidance for finding new high Tc superconductors will also be discussed.

October 2 Quasar Science in the Large Synoptic Survey Telescope Era
Ohad Shemmer (University of North Texas)

The Large Synoptic Survey Telescope (LSST) has been identified by the National Academy of Sciences as the highest priority ground-based observatory of the next decade. With its 8-meter aperture, LSST is designed to monitor frequently about 20,000 square degrees of the southern skies using six photometric bands for ten years. I will provide an overview of the LSST project and highlight its key science goals. In particular, I will describe how LSST will revolutionize our understanding of quasars and how such sources will be utilized as cosmological probes. I will conclude with describing the main challenges the astronomical community will face in light of the enormous data output from the telescope and the steps it is taking in preparation for LSST operations.

October 16 Thirty Meter Telescope: The Next Generation of Ground Based Optical/Infra Red Observatory
Warren Skidmore (Thirty Meter Telescope Observatory Corporation)

After a short construction status update I will discuss some of the observational capabilities that the Thirty Meter Telescope will provide and some of the areas of study that will benefit from the TMT's capabilities. I'll describe how the telescope design was developed to support a broad range of observing capabilities and how the observatory is being engineered. Finally I'll describe the avenues through which astronomers can actively participate in the project; in the planning for a potential TMT/NSF partnership, preparing for the development of 2nd generation instruments and directing the scientific aims for the observatory.

October 23 Interaction of Ferromagnetic and Superconducting Permanent Magnets - Superconducting Levitation
Ludwig Schultz, Institute of Metallic Materials, IFW Dresden and TU Dresden

Abstract TBD

November 3 Magnetic Nanowires: Revolutionizing Hard Drives, RAM, and Cancer Treatment
Beth Stadler, University of Minnesota

Abstract, TBD

November 13 INDUSTRY TALK: Translating Academic Research to a Career in Industry
Mike Borowczak (Erebus Labs)

While there is no singular path from academia to industry this talk focuses on the commonalities, differences and more importantly how to transition from the former to the latter. The discussion is grounded in the presenter's own experiences - having completed a PhD in Computer Science and Engineering and having worked in multiple roles for a Research Hospital as a Bioinformatics Programmer, two Fortune 500 Semiconductor companies as a Hardware Security Architect, and a tech startup as a Data Scientist. The objective of the presentation is to provide an overview of potential avenues and options for students looking to make a transition beyond traditional physics and astrophysics opportunities. Expect a blend of graph theory, information theory, and some straight-talk on the world outside of academia.

February 23 Spin Current: The Torque Wrench of Spintronics
Mark Stiles, NIST

Abstract, TBD

March 25 Title, TBD
Adam Jensen, University of Nebraska at Kearney

Abstract, TBD

April 8 Title:TBD
E. Ward Plummer, Louisiana State University

Abstract, TBD

April 29 Title, TBD
Ashley Ross, The Ohio State University

Abstract, TBD

Previous colloquia series: Fall 2002 Spring 2003 Fall 2003 Spring 2004 Fall 2004 Spring 2005 Fall 2005 Spring 2006 Fall 2006 Spring 2007 Fall 2007 Spring 2008 2008-09 2009-10 2010-11 2011-12 2012-13 2013-14 2014-15
Contact for program information: Adam Myers