REU 2018 Projects
| MENTOR | STUDENT | 2018 PROJECT (click on link to see abstract) |
| Alice Galdi | Mariah Brown Presentation Final Report Mentor Intro |
Abstract: Not available at this time. |
| Jai Kwan Bae, Kevin Nangoi | Gihan Dodanduwa Waduge Presentation Final Report Mentor Intro |
Abstract: Modern femtosecond photoemission electron sources require very high intensity (10s of GW/cm2) ultrafast laser to extract enough quantity of electrons. At such high intensity, the electron occupation function is far from equilibrium and evolves rapidly on sub-ps timescales which results in the electron temperature of several thousands Kelvin. The ultrafast laser heating and multiphoton photoemission effects may play a significant role in emission processes, thereby increasing undesired mean transverse energy of emitted electrons. In this project, the student will model this effect using various computational tools and approaches and, time allowing, will experience developing and operating the photocathode performance measurement system that operates in the femtosecond regime. |
| Nilanjan Banerjee | Chadd Miller Presentation Final Report Mentor Intro |
Abstract: Intrinsic and loaded quality factors of a SRF cavity are important in determining the cryogenic heat load and RF power constraints respectively. Currently, most measurement systems use analogue PLLs to do these measurements which are impractical to use in an cryomodule already in operation. In this project, the student will study and implement various techniques to measure the quality factors for the main linac cavities in the CBETA project using the Cornell LLRF system. The student will also determine which technique yields the minimum uncertainty of measurement and integrate it into the control system for CBETA. https://www.classe.cornell.edu/StudentOpportunities/ReuProgram.html |
| Adam Bartnik | Cait Battle-McDonald Presentation Final Report Mentor Intro |
Abstract: Keeping all parts of a particle accelerator in perfect synchronization is critically important to controlling the dynamics of the particle beam. In CBETA, the Cornell-Brookhaven ERL Test Accelerator, the particles are initially created by shining a pulsed laser beam onto a photo cathode. The arrival of those laser pulses determines when the particles enter the accelerator, and thus must be synchronized to all of the other parts of the accelerator. The interested student will help engineer a new system to maintain this laser synchronization, and also the diagnostics to quantify its performance. |
| William Bergan, Cameron Duncan | Arianna Giguere Presentation Final Report Mentor Intro |
Abstract: Tremendous progress is being made toward software automation of complex tasks, with the operation of particle accelerators being an exciting new frontier for these artificial intelligence (AI) technologies. We are investigating automated, real-time tuning of the Cornell Electron Storage Ring (CESR). The challenge of finding the best AI algorithms for CESR is highly interdisciplinary, demanding insights from physics, mathematics and computer science. The interested student will study one AI algorithm in detail, among choices that include Bayesian optimization and neural networks, and then implement and test their algorithm using existing CESR simulation software. The aim of the student's research is to assess the performance of the algorithm in optimizing beam properties, such as emittance or lifetime, with a view to future deployment on the real accelerator. |
| Jim Crittenden | Eric Biddulph-West Presentation Final Report Mentor Intro |
Abstract: The Cornell-Brookhaven Electron-Recovery-Linac Test Accelerator (CBETA) will provide a 150 MeV electron beam using four acceleration and four deceleration passes through the Cornell Main Linac Cryomodule housing six 1.3-GHz superconducting RF cavities. The return path of this 76-m-circumference accelerator will be provided by 106 fixed-field alternating-gradient (FFAG) cells which carry the four beams of 42, 78, 114 and 150 MeV in a vacuum chamber of 84x24 mm interior dimensions. This REU project concerns the splitter/combiner regions which serve to match the on-axis linac beam to the off-axis beams in the FFAG cells, providing the path-length adjustment necessary to control the acceleration and deceleration for each of the beams. The 2017 REU project determined the definitive engineering design and modeling of the dipole magnets now under construction. The first deliveries of the finished magnets will take place in March. The project will see its first beam through one of the splitter/combiner lines and one FFAG cell in April and May of 2018. Thus the 2018 REU project will assess the initial performance of the splitter magnets. In addition, the remaining complement of 136 magnets for the eight lines will be delivered during the course of the summer, requiring quality assurance tests and installation. The Cornell team carries the additional responsibility for designing and fabricating 19 specialty magnets as the installation of the full facility proceeds apace. |
| Jim Crittenden | Keefer Rowan Presentation Final Report Mentor Intro |
Abstract: The buildup of low-energy electron densities (electron clouds) has been shown to limit the performance of storage rings such as the B-meson factories KEK-B in Japan and PEP-II at the SLAC National Laboratory. The Cornell Electron Storage Ring (CESR) was reconfigured in 2008 as a test accelerator to study the effect of cloud buildup on beam dynamics. The measurement, data analysis, and modeling capabilities of the CESR Test Accelerator project group have matured to a degree of sophistication without peer in the world of accelerator R&D. This summer will see the preparation of two submissions to the Physical Review Accelerators and Beams: 1) detailed modeling of synchrotron-radiation-induced electron production in the CESR vacuum chamber walls with parameters tuned to reproduce measurements of cloud-induced betatron tune shifts along a train of positron bunches, and 2) full-lattice optics calculations incorporating the space-charge fields of the cloud demonstrating how they result in vertical beam size blowup. This 2018 REU project will consist of contributions to these ongoing efforts. |
| Luca Cultrera | Austin Comito Presentation Final Report Mentor Intro |
Abstract: Photocathodes capable of providing high intensity and highly spin-polarized electron beams with long operational lifetimes are of great interest for the next generation nuclear physics facilities like Electron Ion Colliders. In the last decades a lot of effort has been dedicated developing materials that can provide highly polarized electrons for application in microelectronic devices. Some of these materials have the potential to generate photoelectron beams with high degree of polarization others can be used to control the spin orientation of the electron during the transport. To the class of half-metals belong materials that are so called because their band structure show a metallic character for one spin orientation and a semiconducting character (hence with a band gap) for the opposite spin orientation. Another interesting class of material is the one of the so called spin-filter materials. Materials belonging to this latter category can be used to realize tunneling barriers that filter the electrons based on the spin orientation. The spin polarization properties of these materials can be fully exploited only if the temperature of these materials is lowered below their characteristic Curie temperature. To this aim we want to implement a photocathode support for our Mott scattering polarimeter that is able to cool to cryogenic temperatures our samples. The REU student will collaborate in the design/realization/commissioning of such sample holder. |
| Michael Ehrlichman | Emily Thyrum Presentation Final Report Mentor Intro |
Abstract: The nonlinear dynamics of a system with periodic structure can be analyzed using a square matrix. We show that because of the special property of the square matrix constructed for nonlinear dynamics, we can reduce the dimension of the matrix from the original large number for high order calculations to a low dimension in the first step of the analysis. Then a stable Jordan decomposition is obtained with much lower dimension. The Jordan decomposition leads to a transformation to a new variable, which is an accurate action-angle variable, in good agreement with trajectories and tune obtained from tracking. More importantly, the deviation from constancy of the new action-angle variable provides a measure of the stability of the phase space trajectories and tune fluctuation. Thus the square matrix theory shows a good potential in theoretical understanding of a complicated dynamical system to guide the optimization of dynamical apertures. The method is illustrated by many examples of comparison between theory and numerical simulation. In particular, we show that the square matrix method can be used for fast optimization to reduce the nonlinearity of a system. |
| Michael Ehrlichman | Frank Ikponmwen Presentation Final Report Mentor Intro |
Abstract: Multi-objective genetic algorithms (MOGA) are a proven technique for optimizing nonlinearities in particle storage ring. These algorithms are used to maximize the volume of stable particle coordinates. i.e. The objective function is the volume. This project will implement a different objective function that aims to detect chaos by calculating changes in the oscillation frequency of stored particles over long periods of time. This new type of objective function is akin to Frequency Map Analysis, which is widely used not only in accelerator physics, but also astrophysics to calculate the stability of planetary systems. This project will develop an understanding of genetic algorithms, spectral analysis techniques, and coding ability. Candidates should arrive already having some skill with scientific programming. |
| Carl Franck | Samuel Hunt Presentation Final Report Mentor Intro |
Abstract: The participant would be engaged in our effort in X-ray spectroscopy based on inelastic scattering with or without coincident deexcitation radiation. We believe that these techniques provide potent approaches for studying quantum matter. Our focus is on correlated electron behavior and new photon interaction effects in solids and atoms. A project for the summer is likely to be one of the following: development of a new form of detector for deexcitation radiation, analysis, operation or planning for inelastic scattering spectroscopy with or without coincidence detection. |
| Colwyn Gulliford | Antonett Nunez-delPrado Presentation Final Report Mentor Intro |
Abstract: Currently, effort is being made to integrate BMAD, the accelerator physics toolkit used to design the Cornell-BNL Energy Recovery Test Accelerator (CBETA), into the machine control system for use online. While a prototype of this software is now running, many features remain to be implemented: including tracking of entire particle bunches and the effects of the self-repulsive forces of low energy electrons, an effect that BMAD doe not simulate, but is crucial to capturing the dynamics of the beam in the low energy portion of the accelerator. The goals of this project thus include: investigating the possible use of other simulations codes (for example we currently simulate the low energy section with the space charge code GPT), the development/deployment of a modular controls system-to-simulation integration scheme and system benchmarking. Successful completion of this project will require developing a working knowledge of basic accelerator physics, and how these dynamics are simulated. |
| Matthias Liepe, Pete Koufalis, Ryan Porter | Spencer Halls Presentation Final Report Mentor Intro |
Abstract: During the cryogenic performance test of superconducting radio-frequency (SRF) cavities, large scale, high sensitivity temperature mapping is used to determine the distribution of the RF losses along the wall of the cavity. This requires operating hundreds of temperature sensors at cryogenic temperatures of a few Kelvin. As part of this project, you will work on commissioning a new temperature mapping system with much increased data sample rates and resolution. You will test readout electronics and write software for data acquisition and data analysis, and participate in the cryogenic testing of SRF cavities. |
| Jim Shanks | Grace King Presentation Final Report Mentor Intro |
Abstract: The Cornell Electron/Positron Storage Ring (CESR) primarily operates as an x-ray light source for the Cornell High Energy Synchrotron Source (CHESS). This summer CESR will undergo an upgrade (CHESS-U), replacing one-sixth of the storage ring circumference with a new magnet structure in order to improve x-ray brightness by up to 1000-fold in some cases. However, the CHESS-U upgrade will not push CESR to its absolute limit. By recycling components from another accelerator that will undergo an upgrade in the next five years, it may be possible to increase the brightness by up to an additional 100-fold, putting CESR in league with the best light sources in the world. This project would explore options for accelerator optics layout and design to maximize the improvement from such an upgrade. The student would be responsible for optimizations of the accelerator layout, linear optics, and nonlinear lattice properties. |
| Louisa Smieska | Sarah Deutsch Presentation Final Report Mentor Intro |
Abstract: Synchrotron scanning probe measurements such as x-ray fluorescence or x-ray diffraction provide highly detailed images of elemental or crystallographic phase distributions in objects ranging from geological samples to plants to works of art. A major challenge in interpreting these rich datasets is understanding relationships between distributions of individual elements or phases, which are often limited to two or three components at a time in correlation plots or overlaid maps. This project will explore and evaluate computational approaches to quantifying and visualizing compositional variations. As a case study, this project will examine scanning x-ray fluorescence and diffraction datasets collected from seven 13th- to 16th-century fragments of illuminated manuscripts from the Cornell Library Rare and Manuscript Collections. |
| Duncan Sutherland | Oscar Jaramillo Perez Presentation Final Report Mentor Intro |
Abstract: Recent advances in electron sources have brought ultrafast pulsed-probe electron diffraction (UED) experiments to the bench top. The increased transverse coherence length and femtosecond time domain of the electron source provides access to structural dynamics of large lattice spacing materials (e.g. proteins, charge density waves, and superlattice structures) induced by laser excitation. Probing different materials will require a proper diffraction chamber setup including: fine enough control to manipulate and align multiple samples within the two different beams (electron and optical), and properly collect and record the UED data. The expectation of the student on this project is to aid in design and assembly of the diffraction chamber and analysis system. |
