Spring 2014

Colloquia - Spring 2014

January 16 - Yue Hao, Brookhaven National Lab

"Accelerator R&D Towards the Next QCD Frontier"

Abstract:

An Electron-Ion Collider (EIC) is required by the quantitative QCD studies of quarks and gluons. Accelerator physicists in US are striving to carry out the next EIC, that has 100x luminosity than the only EIC in the history, HERA. The design of eRHIC, the Brookhaven National Lab¹s EIC, adopts a linac-ring scheme to achieve the luminosity boost. This talk will review snapshots of design challenges of eRHIC and explore the opportunity of new accelerator physics advancement in this design process.

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm


January 28 - Tim Gay, University of Nebraska

"Why Isn't God Amibidextrous?"

Abstract:

Until 1957, scientists thought that the fundamental laws of Nature must be the same whether they were applied to our Universe or the Universe that is a mirror reflection of our own. The implications of the discovery that this is not true - essentially that Nature is "handed" - will be discussed. Some interesting applications of handedness, or "chirality" in agriculture, biology, chemistry, and physics will be presented. I will also talk about some new physics experiments on chirality that may shed light on how life began on this planet.

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm


January 30 - Nathaniel Pogue, Texas A&M (NOTE: Different Day and Location)

"The Strong Focusing Cyclotron and its Applications"

Abstract:

The Strong Focusing Cyclotron (SFC) is a novel, compact, cost effective, and powerful accelerator that is unlike any previous cyclotron designed to date. The SFC has the capability to produce high -current proton, ion, and muon beams that can be utilized for various applications such as Accelerator Driven Systems, isotope production, neutron generation, and the High Intensity Frontier. The accelerator, when built, will be the highest power accelerator in the world with its 10 mA CW beam at 800 MeV. Technology developed for the SFC also has vast implications in beam therapy gantry design and the High Energy Physics Frontier. Additionally, recent results from the Texas A&M SRF program will be presented.

Presentation: Auditorium in Engineering Bldg. @ 3:00 pm

Refreshments: OCNPS 200 Atrium @ 2:30 pm

February 4 - Balsa Terzic, Jefferson Lab.

"Appllications of Modern Computational Tools in Accelerator Physics"

Abstract:

In this overview talk, I will present two new computational tools that can be employed to solve previously intractable accelerator physics problems. One such computational tool is genetic algorithm (GA), which is effective in multidimensional, nonlinear optimization, especially in the higher-dimensional realm where traditionaIn this overview talk, I will present two new computational tools that can be employed to solve previously intractable accelerator physics problems. One such computational tool is genetic algorithm (GA), which is effective in multidimensional, nonlinear optimization, especially in the higher-dimensional realm where traditional methods fail. The other is parallel computation on Graphical Processing Units (GPUs), which can speed up intrinsically parallelizable algorithms by a few orders of magnitude, thereby making historically computationally prohibitive capabilities and domains of application feasible. I will motivate the use of these techniques, briefly cover the main concepts, and outline several applications where they have been successfully applied, including: optimization of the working point in a particle collider, non-linear chi-square fitting, beam-beam simulations, and simulation of coherent synchrotron radiation.

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm


February 6 - He Zhang, Jefferson Lab (NOTE: Different Day and Location)

"Space Charge Effect Simulation Using DA Based FMM and Electron Cooling Simulation for JLab's MEIC Project"

Abstract:

In the first part of the talk, a method will be presented that allows the computation of space charge effects of arbitrary and large distributions of particles in an efficient and accurate way based on a variant of the Fast Multipole Method (FMM). It relies on an automatic multigrid-based decomposition of charges in near and far regions and the use of high-order differential algebra (DA) methods to obtain decompositions of fields that scales with a high power of the order. Given an ensemble of N particles, the computational expense scales as O(N). Simulation results on the photoemission process and bunch evolution during the creation of a femtosecond electron bunch will also be presented. The second part of the talk will include a brief introduction of Jefferson Lab's MEIC project and simulation results on its electron cooling system, which is crucial to achieve high brilliance.

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm


March 18 - Ilya Larin, ITEP, Moscow, Russia

"The Lifetime of the Neutral Pion"

Abstract:

A precision measurement of the neutral pion lifetime via the Primakoff effect was carried out by the PrimEx experiment at Jefferson Lab using the Hall B photon tagger and a high-resolution electromagnetic calorimeter. The neutral pion lifetime was extracted from the measured cross sections using theoretical models. The result of this fundamental quantity is 2.5 times more precise than the present world average of all measurements as reported in the Particle Data Book and consistent with current theoretical predictions.

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm

April 1 - Rocco Schiavilla, Old Dominion University

"Solar Neutrinos: The Story Of A Problem And Its Solution"

Abstract:

The physics of neutrinos is currently one of the most active fields of research in astrophysics and particle physics. In this talk I will discuss the solar neutrino problem and how its recent solution has provided confirmation for a strange property of neutrinos, postulated by Pontecorvo in the late fifties: the property of flavor oscillations

Presentation: OCNPS 200 @ 3:00 pm

Refreshments: Atrium @ 2:30 pm


April 8 - Ron Gilman, Rutgers University

"The Proton Radius Puzzle: Even More Puzzling"?

Abstract:

The difference between the proton radius measured with muons vs with electrons is called the Proton Radius Puzzle. Four years have passed since the Puzzle arose, and many potential explanations have been ruled out, and arguably none of the remaining explanations is favored by a majority of the community. I will describe the Puzzle and current experimental efforts to resolve it.

Presentation: OCNPS 200 @ 3:00 pm

Refreshment: Atrium @ 2:30 pm


April 15 - Silviu Corvig, Jefferson Lab

"Designing High Power Targets with Computational Fluid Dynamics "

Abstract:

Jefferson Lab is a fixed target facility that studies the structure of the building blocks of nature. High power targets, up to 1000 W, have been widely used at Jefferson Lab for two decades with mixed performance results. The liquid hydrogen target for the Qweak experiment was the first target designed with Computational Fluid Dynamics (CFD) and it has been the best performing target at Jefferson Lab. The Qweak target was the highest power liquid hydrogen target in the world at 2500 W. A CFD facility has been established at Jefferson Lab to support target designs for the 12 GeV physics program. The CFD facility will design the 5000 W liquid hydrogen target for the future MOLLER experiment in Hall A. I will be presenting the state of the CFD facility.

Presentation: OCNPS 200 @ 3:00 pm

Refreshment: Atrium @ 2:30 pm


April 22 - Matthew Shepherd, Indiana University

"The ongoing quest to understand the QCD spectrum of mesons "

Abstract:

For many decades the conventional quark anti-quark picture of mesons has provided a satisfactory description of the experimentally observed spectrum of mesons. In recent years, strong experimental evidence of meson states that cannot be formed by a quark anti-quark pair has emerged. At the same time, recent first-principles calculations of the meson spectrum from quantum chromodynamics (QCD) have suggested the presence of unconventional meson states. However, the correspondence between newly-discovered unconventional states and predicted states is not immediately apparent. In this talk I'll motivate using meson spectroscopy as a tool for studying QCD, discuss a selection of recent experimental results, and future prospects for studying the meson spectrum.

Presentation: OCNPS 200 @ 3:00 pm

Refreshment: Atrium @ 2:30 pm


April 29 - Senior Thesis Presentations, Physics Awards, Sigma Pi Sigma Inductions

Brett Hagood
"Observing Anderson Localization."

Colton Katsarelis
"Pitting Corrosion of Aluminum Alloy 5086 on Navy Patrol Boats."

Timothy Naginey
"Estimating Positronium Formation for Plasma Applications."

Brandon DeMello
"PythonPWA Toolkit and Data Simulation for Partial-Wave Analysis Projects at The Thomas Jefferson National Accelerator Facility."

Eric Stacy
"Classical Trajectory Monte Carlo Calculations of Positronium Formation in Positron Neutral Atom Collisions."

James Porter
"Scintillation Detector Testing and Repair."

Canniggia Deslandes
"Polarization Spectroscopy in a Neon Discharge."

Connor Schwalm
"Understanding the Light Curve of AX Persei."

Presentation: ECSB 1202 Auditorium (CAVE) from 3:00 - 4:30 pm.

Refreshment: OCNPS 0200 Atrium from 2:15 - 2:50 pm.