Spring 2017 Colloquium Series

February 15, 2017January 9, 2019

Inside the Iran Deal: The Making and Future of a Historic Agreement

SPEAKER:

R. SCOTT KEMP

NORMAN C. RASMUSSEN ASSOCIATE PROFESSOR OF NUCLEAR SCIENCE AND ENGINEERING

MIT LABORATORY FOR NUCLEAR SECURITY AND POLICY

MASSACHUSETTS INSTITUTE OF TECHNOLOGY (MIT)

DATE/TIME:

MON, 02/15/2017 - 4:00PM TO 5:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2017 Colloquium Series

Abstract:

Scott Kemp of MIT will tell the story of the technical negotiations behind the Iran nuclear agreement and discuss the prospects for the agreement continuing under a new U.S. administration. The original calculations and trade-offs that were made behind the scenes will be revealed, including several inadvertent loopholes introduced into the agreement, and conclusions drawn about Iran's ultimate ability to make nuclear weapons. The implications of these findings, and thoughts on how to preserve the security benefits of this historic diplomatic achievement, will be discussed.

About the Speaker:

R. Scott Kemp is the Norman C. Rasmussen Associate Professor of Nuclear Science and Engineering at MIT, and director of the MIT Laboratory for Nuclear Security and Policy.

Scott's research combines physics, information science, politics, and history to help define policy options for achieving international security under technical constraints. He works on direct verification of nuclear-warhead dismantlement, the detection of clandestine nuclear programs, and on emerging nuclear technologies that complicate international security.

In 2010 and 2011, he served as Science Advisor in the U.S. State Department's Office of the Special Advisor for Nonproliferation and Arms Control where he was responsible for framing the technical negotiations on Iran's nuclear program. He is the recipient of the NEC Award in Computation and Communication and the 2016 Sloan Research Fellowship in Physics.

Scott received a Ph.D. from Princeton University in International Affairs, and a bachelor's in Physics from the University of California, Santa Barbara. At MIT he teaches courses on nuclear power, civil society, and on reducing the dangers of nuclear weapons.

February 6, 2017January 9, 2019

High-flux helium and hydrogen plasma exposure of materials for magnetic fusion

SPEAKER:

ROBERT D. KOLASINSKI

ENERGY INNOVATION DEPARTMENT

SANDIA NATIONAL LABORATORIES

DATE/TIME:

MON, 02/06/2017 - 4:00PM TO 5:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2017 Colloquium Series

Abstract:

It is widely recognized that the science of plasma-material interactions (PMI) is central to the realization of magnetic fusion as an energy source. Predicting how materials behave in the extreme environments characteristic of fusion devices remains among the most daunting and complex technical challenges in materials science. Surfaces directly exposed to intense plasmas will be reconstituted many times over their designed operational lifetime. This surface evolution governs not only how materials degrade, but is also intimately coupled to the effect of neutral and impurity recycling and edge turbulence on the core plasma.

This talk will focus on one of the most challenging aspects of the PMI problem: how the intense fluxes of low-energy species (e.g. shallowly implanted hydrogen and helium) affect the structure of solid plasma-facing components. I will emphasize our recent experimental work to decipher the mechanisms that underlie this surface modification, including surface-to-bulk transport, defect nucleation, nanostructure growth, and stresses induced in materials during plasma exposure. A key component of our experimental program at Sandia/CA involves a collaboration using the tritium plasma experiment (TPE), a linear plasma device located at Idaho National Laboratory capable of exposing materials to high-flux tritium plasmas and handling neutron-damaged metals. Our recent work focuses on understanding insoluble gas precipitation in plasma-exposed tungsten and how different microstructures (including advanced ultra-fine grained materials) affect bubble growth. Given the tremendous capacity of near-surface bubbles to trap diffusing atomic species, precipitation will have significant implications for tritium inventory in large magnetic fusion experiments, including ITER. At a more fundamental level, we have also studied hydrogen adsorption on surfaces using low energy ion scattering, a form of low-energy ion beam analysis. Because of its high surface-sensitivity, LEIS can be used to detect the presence of hydrogen adatoms on surfaces precisely, providing insight into surface binding energies. I will present some of our recent results aimed at understanding recombination and exchange on tungsten and beryllium surfaces. I will conclude with a short summary of plans for upcoming diagnostic development.

About the Speaker:

Robert Kolasinski is a Principal Member of the Technical Staff in the Energy Innovation Department at Sandia National Laboratories, in Livermore, CA. While at Sandia, Rob’s research efforts have focused on plasma-material interactions for magnetic fusion energy, hydrogen storage, and infrastructure for fuel cell electric vehicles. Rob received M.S. (2001) and Ph.D. (2007) degrees from the California Institute of Technology in mechanical engineering following undergraduate study at Rutgers University. While at Caltech, he studied ion-surface interactions in plasma propulsion systems as part of an extensive collaboration with the Advanced Propulsion Group at the NASA Jet Propulsion Laboratory. In 2016, Rob was selected for Department of Energy Office of Science Early Career Award.

Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

January 30, 2017January 9, 2019

Overview of the FASt TEst Reactor (FASTER)

SPEAKER:

FLORENT HEIDET

DATE/TIME:

MON, 01/30/2017 - 4:00PM TO 5:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2017 Colloquium Series

Abstract:

Over the past couple years Argonne National Laboratory has been developing a FASt TEst Reactor as part of the DOE-NE Advanced Reactor Campaign in order to address the growing needs for fast neutron irradiation capabilities. FASTER is a 300 MW_th sodium-cooled fast reactor relying on well-established technologies in order to provide both reliable testing capabilities and high availability factor. An overview of the FASTER design will be presented. The design process used, core design, plant layout and safety analysis results will all be discussed. Irradiation and test capabilities offered by the FASTER design will also be highlighted, including the closed loops incorporated in the design. A unique feature of FASTER is that not only it offers very high fast fluxes and large irradiation volumes, but it can also offer very high thermal fluxes by making use of the large neutron leakage probability. This would enable FASTER to support R&D for both fast spectrum and thermal spectrum systems.

About the Speaker:

Florent Heidet is a Principal Nuclear Engineer at Argonne National Laboratory. Florent studied mechanical engineering in France where he obtained a Master of Science in 2006, and nuclear engineering at the University of California, Berkeley where he obtained a Ph.D. in 2010. Florent joined Argonne National Laboratory where he worked on advanced reactors systems and associated fuel cycles. As part of the collaboration between Argonne and KAERI on developing the Prototype Gen-VI Sodium-cooled Fast Reactor, to start operation in South Korea by 2028, Florent was the lead core designer for the Argonne team. Over the past couple years Florent also lead the core design for the test reactor concept, FASTER, being developed by Argonne as part of the DOE Advanced Reactor campaign. In addition of his work at Argonne, Florent is also involved with the American Nuclear Society where he is serving as an officer of the Reactor Physics Division and in multiple committees.

January 23, 2017December 19, 2018

Detailed Modeling of Fission

SPEAKER:

RAMONA VOGT

NUCLEAR AND CHEMICAL SCIENCES DIVISION, LLNL

PHYSICS DEPARTMENT, UC DAVIS

DATE/TIME:

MON, 01/23/2017 - 4:00PM TO 5:00PM

LOCATION:

3105 ETCHEVERRY HALL

Spring 2017 Colloquium Series

Abstract:

For many years, the state of the art for treating fission in radiation transport codes has involved sampling from average distributions. In these average fission models energy is not explicitly conserved and none of the outputs are correlated because all particles (fission fragments, neutrons and photons are considered) are emitted independently. However, in a true fission event, the energies, momenta and multiplicities of the emitted particles are correlated. Such correlations are interesting for many modern applications. Event-by-event generation of complete fission events retains information for all particles emitted, making it possible to extract any desired correlation observable. These complete event simulations can be included in general Monte Carlo transport codes. In this talk, the types of available data for model input and validation are presented. The physics of one such complete event fission simulation code, FREYA, is described in some detail. Comparison is then made between some currently available phenomenological models of fission for some important neutron observables. Specific neutron correlations and their sensitivity to model inputs are then discussed.

About the Speaker:

Ramona Vogt is a staff physicist at Lawrence Livermore National Laboratory and an adjunct professor of physics at UC Davis. She obtained an AS degree from Kaskaskia College in 1983 and a BS in physics from the University of Illinois Urbana-Champaign in 1985. She received her PhD in nuclear physics from the State University of New York at Stony Brook in 1989. After postdoctoral positions in LLNL and GSI in Darmstadt, Germany she was a staff scientist at LBNL until she returned to take her staff appointment at LLNL in 2007. She became an adjunct professor of physics at UC Davis in 1995. She was named Fellow of the American Physical Society in 2010 and APS Outstanding Referee in 2016. She has been active in the APS, serving in various posts for the Executive Committee of the Topical Group on Hadronic Physics since 2008 and is currently a member of the DNP Program Committee.