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Full-Text Articles in Physics

Developing Process Variables Necessary To Operate Simulacrum: The Lcls Accelerator Simulator, Mirian G. Juan Estrella Sep 2019

Developing Process Variables Necessary To Operate Simulacrum: The Lcls Accelerator Simulator, Mirian G. Juan Estrella

STAR Program Research Presentations

The Linac Coherent Light Source (LCLS) is a free electron laser that is located at SLAC National Accelerator Laboratory. It fires 120 pulses per second, creating x-ray snapshots of materials at the atomic and molecular level as it undergoes any changes or processes. This resulted in many scientific discoveries in chemistry, biology, energy science, and technology. Now, there is a new vision at SLAC regarding LCLS: to develop Simulacrum. Simulacrum is a system that simulates LCLS and its control system. Within Simulacrum there exits services that contain process variables that measure specific parts of a device on LCLS, which communicate …


Measuring Length Of Electron Bunches With Optics In Lcls-Ii, Nathan Ahn, Alan Fisher Sep 2019

Measuring Length Of Electron Bunches With Optics In Lcls-Ii, Nathan Ahn, Alan Fisher

STAR Program Research Presentations

Since the launch of the LINAC Coherent Light Source (LCLS) in 2009, there have been over 1,000 publications enabling pioneering research across multiple fields. Advances include: harnessing the sun’s light, revealing life’s secrets and aiding drug development, developing future electronics, designing new materials and exploring fusion, customizing chemical reactions, and many more. These discoveries gathered worldwide attention, and now work has begun on a new revolutionary tool, LCLS-II. The LCLS-II will pulse at a million times a second, compared to the 120 pulses from the LCLS. Within the LCLS-II, there are two chicanes, serpentine curves. As the electron beam passes …


Pnnl Dark Matter Bubble Chamber Simulation, Carl M. Krutz Aug 2019

Pnnl Dark Matter Bubble Chamber Simulation, Carl M. Krutz

STAR Program Research Presentations

Based on observations of interactions between objects on a cosmic scale, scientists have determined that a large percentage (85%) of the universe’s mass is not visible. Weakly Interacting Massive Particles (WIMPs) are one of the primary candidates for this dark matter. Many current projects seek to find WIMPs through various search methods. The PICO dark matter experiment involves observing an underground chamber at SNOLAB for bubbles created when energy in the form of radiation is deposited in a superheated liquid. The group at Pacific Northwest National Lab (PNNL) working on the PICO project seeks to develop improvements to the project’s …


Low Cost Timing System For High Precision Particle Detection, Eric Madrigal, Sasha Dolgashev, Vi Tran Jan 2019

Low Cost Timing System For High Precision Particle Detection, Eric Madrigal, Sasha Dolgashev, Vi Tran

STAR Program Research Presentations

The project goal was to find a way to make a low-cost high precision timing system. High precision timing systems are already on the market, however, at a high cost. Various particle research projects need a large number of timers, so a substantial budget is required. In order to bypass the need for a large enough budget, commercially available parts were used and tested. The timing system consisted of multiple parts with different low-cost microchips and counters. In order for the project to meet its goal, the timers need to work under 50 picoseconds. Although some tests showed the timers …


Ultra-Fast X-Ray Diffraction Of Metastable Structures During Hydrogen Crystallization, Andrew Pham Jan 2019

Ultra-Fast X-Ray Diffraction Of Metastable Structures During Hydrogen Crystallization, Andrew Pham

STAR Program Research Presentations

Big discoveries can come from small element, and hydrogen is the simplest element in the universe, but its property has been intensely studied in recent years. Hydrogen has a notably complex phase diagram, and its application is important to many scientific fields, such as fundamental physics, inertial confinement fusion, planetary sciences, etc. While sophisticated static observations have probed its structure at extremely high pressures, the higher-temperature studies applying dynamic compression is confined to optical measurement methods. In this project over the summer, I will present spectrally resolved x-ray scattering assessment from plasmons in dynamic compressed deuterium. Collaborating Compton scattering and …


Memory In A Contact Line, Charity Lizardo, Esmeralda Orozco, Audrey Profeta, Nathan C. Keim Jan 2019

Memory In A Contact Line, Charity Lizardo, Esmeralda Orozco, Audrey Profeta, Nathan C. Keim

STAR Program Research Presentations

We study the behavior of the liquid-solid-vapor contact line of water held in a narrow gap between two plates. A syringe pump injects and withdraws a constant, small volume of the water, driving the contact line back and forth repeatedly and changing its shape. We take photos of the contact line after each cycle. Comparing subsequent images to each other, we find that after several cycles the contact line reaches one of two steady states: a reversible steady state, where the shape is not changing, or a fluctuating steady state, where the shape continues to change slightly. Experiments on acrylic …


Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim Sep 2018

Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim

STAR Program Research Presentations

When a body of liquid sits on a surface, an irregular border between the wet and dry regions of the surface exists, called the contact line. Driving this contact line back and forth repeatedly can change its shape.We use a syringe pump to cyclically infuse and withdraw a predetermined volume of water, and take photos of the contact line after each cycle. Comparing these images to each other determines if the contact line is returning to the same shape. We find that below a critical value of infused volume, after many cycles the contact line reaches a steady state in …


Anisotropic Conductive Adhesives For Interdigitated Back Contact (Ibc) Silicon Solar Cells, Katherine M. Lohmuste, Manuel Schnabel, Maikel F.A.M. Van Hest Aug 2018

Anisotropic Conductive Adhesives For Interdigitated Back Contact (Ibc) Silicon Solar Cells, Katherine M. Lohmuste, Manuel Schnabel, Maikel F.A.M. Van Hest

STAR Program Research Presentations

The current manufacturing process for solar panels using interdigitated back contact (IBC) silicon solar cells involves a multi-step metallization and interconnection process in which a substantial amount of silver is used. This work focuses on a new process using conductive adhesives (CA) which would increase efficiency and lower cost through a one-step metallization and interconnection process that combines with encapsulation using little silver and only requiring metal patterning on the back sheet or back glass. It would also not require direct metallization of the silicon, which would result in fewer defects, while increasing voltage and therefore efficiency. Silver-coated Poly(Methyl Methacrylate) …


X-Ray Spectroscopy Of Nio And Nanodiamond At Ssrl, Jackson Earl Jan 2018

X-Ray Spectroscopy Of Nio And Nanodiamond At Ssrl, Jackson Earl

STAR Program Research Presentations

The first aspect of this research project focuses on investigating the surface chemistry of high pressure high temperature (HPHT) nanodiamond by using X-ray spectroscopy techniques at the Stanford Synchrotron Radiation Lightsource (SSRL). HPHT nanodiamond is being examined as a biosensing tool for electric field detection based on the fluorescent nitrogen vacancy center hosted within diamond. With use of the transition edge spectrometer (TES), a state-of-the-art X-ray fluorescence detector, we are able to probe the surface and bulk properties of diamond. Preliminary work using density functional theory (DFT) has been done, offering insight into ground state energies and electronic structure. DFT …


Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen Jan 2018

Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen

STAR Program Research Presentations

The Large Synoptic Survey Telescope (LSST) is a ground-based telescope that will survey the Southern sky every few nights. Located in the telescope will be a 3.2 gigapixel digital camera. To ensure proper instrumentation of the camera, there must be a monitored stable temperature. As part of my research, I assembled resistance temperature detectors and tested them to verify their reliability in measuring temperature in the camera’s cryostat refrigeration cooling system. Resistance temperature detectors function by the principle of thermal resistivity, in which their electrical resistances vary as temperature varies. Through testing, I was able to determine whether these particular …


Optimizing The Telescope Assembly Alignment Simulator For Sofia, Zoe E. Sharp, Alex Quyenvo, Jennifer Briggs, Brian Eney Oct 2016

Optimizing The Telescope Assembly Alignment Simulator For Sofia, Zoe E. Sharp, Alex Quyenvo, Jennifer Briggs, Brian Eney

STAR Program Research Presentations

The Stratospheric Observatory for Infrared Astronomy (SOFIA) conducts research on a modified Boeing 747sp aircraft. By using a variety of infrared science instruments mounted on a 2.7 meter telescope, researchers can make discoveries about the galactic center, star formation, and various topics associated with a deeper understanding of our universe. To efficiently collect data through the SOFIA instruments, the instruments must be tested and prepared prior to being placed on the aircraft. Therefore, with the use of the Telescope Assembly Alignment Simulator (TAAS), researchers can design and construct improvements needed for these instruments to efficiently perform while in flight. The …


An Analysis Of The Microseismic Peak At Ligo Hanford Observatory, Nathan Sweem Oct 2016

An Analysis Of The Microseismic Peak At Ligo Hanford Observatory, Nathan Sweem

STAR Program Research Presentations

The Laser Interferometer Gravitational-Wave Observatory (LIGO) consists of two facilities, LIGO Hanford Observatory (LHO) and LIGO Livingston Observatory (LLO). Gravitational-wave astronomy began when LIGO observed gravitational-waves for the first time in 2015 during the inaugural observation run (01) of the advanced detector era. Isolation of LIGO detectors from seismic noise is necessary to achieve a desired level of performance. Analysis of seismic noise is essential to make improvements in seismic isolation, and to validate gravitational-wave candidates with a high degree of certainty. Hourly trends of seismic noise in the 0.1 – 0.3 Hz frequency band from Guralp CMG-40T three-axis seismometers …


Measurement And Modeling Of Cosmic Ray Exposure For Supercdms Dark Matter Detectors., Kameron Mccall, John Orrell, Jared Yamaoka Oct 2016

Measurement And Modeling Of Cosmic Ray Exposure For Supercdms Dark Matter Detectors., Kameron Mccall, John Orrell, Jared Yamaoka

STAR Program Research Presentations

Dark matter is an unknown type of matter that composes roughly 27% of the observable universe and, as cosmological structure models suggest, the earth should be passing through a “dark halo” of this unknown matter present in the Milky Way galaxy. As we pass through this halo, the Super Cryogenic Dark Matter Search (SuperCDMS) experiment aims to directly detect dark -matter particles. Though many dark matter particle candidates exist, SuperCDMS focuses on the detection of particles called WIMPS (weakly interacting massive particles) as predicted by super-symmetric theories beyond the standard model. Due to the high-sensitivity of the germanium detectors employed, …


Exploring Mathematical Strategies For Finding Hidden Features In Multi-Dimensional Big Datasets, Tri Duong, Fang Ren, Apurva Mehta Oct 2016

Exploring Mathematical Strategies For Finding Hidden Features In Multi-Dimensional Big Datasets, Tri Duong, Fang Ren, Apurva Mehta

STAR Program Research Presentations

With advances in technology in brighter sources and larger and faster detectors, the amount of data generated at national user facilities such as SLAC is increasing exponentially. Humans have a superb ability to recognize patterns in complex and noisy data and therefore, data is still curated and analyzed by humans. However, a human brain is unable to keep up with the accelerated pace of data generation, and as a consequence, the rate of new discoveries hasn't kept pace with the rate of data creation. Therefore, new procedures to quickly assess and analyze the data are needed. Machine learning approaches are …


Optimization And Coding Of A Lcls Control Program, Tanner M. Worden Sep 2016

Optimization And Coding Of A Lcls Control Program, Tanner M. Worden

STAR Program Research Presentations

SLAS’s, Linac Coherent Light Source (LCLS) also known as X-ray free-electron laser (XFEL) is the first X-ray laser of its kind. It gave Scientist from around the world the unique ability to observe the world at a subatomic level. Allowing for major advancements in the field of biological chemistry, drug science, material science and many more. Since the LCLS is a fairly unique scientific instrument, the demand for its use by the scientific community has always been high since it turned on back in 2009. This means that any and all time that the laser is not being used for …


Understanding Molecular Bonding In Vitamin B12 Using X-Ray Spectroscopy, Jamie N. Lehnen Jan 2016

Understanding Molecular Bonding In Vitamin B12 Using X-Ray Spectroscopy, Jamie N. Lehnen

STAR Program Research Presentations

It is often difficult to accurately describe the electronic configuration of large molecules like cobalamin (Vitamin B12). By defining the electronic and geometric structure of a molecule using X-ray spectroscopy, we can better understand how that molecule behaves. Cobalamin is a molecule of interest because it typically displays dehalogenating properties in the body. By understanding more of how cobalamin analogues operate, it becomes possible to know their chemical properties and reactions.


Drag Reduction Using Graphene In Viscous Laminar Flow With Water And Isopropanol, Jessica M. Patalano, Akm Newaz Dr. Jan 2016

Drag Reduction Using Graphene In Viscous Laminar Flow With Water And Isopropanol, Jessica M. Patalano, Akm Newaz Dr.

STAR Program Research Presentations

America has over 2.6 million miles of pipeline for the transportation of energy products, such as liquid petroleum and natural gas. Friction is one of the main sources for energy dissipation at liquid/solid interfaces that limits the transport of a fluid through a cylindrical pipe or tube. In order to make these pipelines more efficient and enhance the flow of these materials, it is necessary to find a coating material that reduces the frictional drag. The ideal material would reduce the drag between the fluid and solid interface while being easily synthesizable on the surface. The goal of this project …


Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell Aug 2015

Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell

STAR Program Research Presentations

Pacific Northwest National Laboratory (PNNL) is currently developing an ultra-low background liquid scintillator counter (ULB LSC) in the shallow underground laboratory. At a depth of 35-meters water-equivalent, the underground laboratory has a multi-layered shielding to keep out cosmic-ray induced background. The ULB LSC, which is located in a clean room facility, is a multi-layered design made up of various materials, including plastic scintillator veto panels, borated polyethylene, lead and copper. These layers help lower the contributions of the terrestrial background and intrinsic background, resulting from the impurities present in the materials, to the overall background count rate observed by the …


Mapping Open Water Bodeis With Optical Remote Sensing, Mary Ellen O'Donnell, Erika Podest Aug 2015

Mapping Open Water Bodeis With Optical Remote Sensing, Mary Ellen O'Donnell, Erika Podest

STAR Program Research Presentations

There is interest in mapping open water bodies using remote sensing data. Coverage and persistence of open water is currently a poorly measured variable due to its spatial and temporal variability across landscapes, especially in remote areas. The presence and persistence of open water is one of the primary indicators of conditions suitable for mosquito breeding habitats. Predicting the risk of mosquito caused disease outbreaks is a required step towards their control and eradication. Satellite observations can provide needed data to support agency decisions for deployment of preventative measures and control resources. This study, which will try to map open …


Calculating The Energy Barriers Required To Join Metal-Organic Framework Synthesis Intermediates With Non-Equilibrium Molecular Simulation, Marcus A. Tubbs, David Cantu, Roger Rousseau, Vassiliki-Alexandra Glezakou Aug 2015

Calculating The Energy Barriers Required To Join Metal-Organic Framework Synthesis Intermediates With Non-Equilibrium Molecular Simulation, Marcus A. Tubbs, David Cantu, Roger Rousseau, Vassiliki-Alexandra Glezakou

STAR Program Research Presentations

Metal organic frameworks (MOFs) are synthetic materials made of a cage-like lattice of metal nodes connected by organic linkers. The pores between the nodes define the characteristics of the material. A MOF, MIL-101, has shown great capacity in the adsorption of carbon dioxide and methane, as well as in hydrogenation catalysis with palladium. While there has been success in synthesizing MIL-101 and other MOFs, the mechanistic details behind their assembly remain unknown. Understanding the synthesis mechanism is necessary to understand the kinetics involved and be able to produce this useful material on an industrial scale. Using MIL-101 as a prototypical …


Laser Frequency Stabilization For Lisa, Andrew B. Parker, Andrew J. Sutton, Glenn De Vine Aug 2014

Laser Frequency Stabilization For Lisa, Andrew B. Parker, Andrew J. Sutton, Glenn De Vine

STAR Program Research Presentations

This research focuses on laser ranging developments for LISA (Laser Interferometer Space Antenna), a planned NASA-ESA gravitational wave detector in space. LISA will utilize precision laser interferometry to track the changes in separation between three satellites orbiting 5 million kilometers apart. Specifically, our goal is to investigate options for laser frequency stabilization. Previous research has shown that an optical cavity system can meet LISA's stability requirements, but these units are large and heavy, adding cost to the implementation. A heterodyne Mach-Zehnder interferometer could be integrated onto LISA’s existing optical bench, greatly reducing the weight, provided the interferometer meets the stability …


Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory, Carey L. Baxter Aug 2014

Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory, Carey L. Baxter

STAR Program Research Presentations

NASA’s Cold Atom Lab (CAL) is a multi-user facility designed to study ultra-cold quantum gases in the microgravity environment of the International Space Station (ISS). One of the main goals of CAL is to explore the unknown territory of extremely low temperatures—possibly as low as the picokelvin range!—where new and fascinating quantum phenomena can be observed. At such temperatures matter stops behaving as particles and instead becomes macroscopic matter waves. CAL will be remotely controlled to perform a multitude of experiments and is scheduled to launch in 2016. In order to anticipate problems that might occur during and post-launch, including …


A Prototype Microwave Cavity Control Circuit For Use In Next Generation Free Electron Laser, Josh Thompson, Peter Neal Barrina, Jiayi Jiang, Joe Frisch, Steve Smith, Daniel Van Winkle Aug 2014

A Prototype Microwave Cavity Control Circuit For Use In Next Generation Free Electron Laser, Josh Thompson, Peter Neal Barrina, Jiayi Jiang, Joe Frisch, Steve Smith, Daniel Van Winkle

STAR Program Research Presentations

One of the current programs at SLAC National Accelerator Laboratory is the Linac Coherent Light Source, or LCLS. Using the existing hardware of the last third of their linear accelerator (or “linac”), SLAC has created one of the most energetic X-ray free electron lasers (or “FEL”). Since 2009, LCLS has used this FEL to perform a wide range of experiments across all sciences, most notably ultrafast filming at the molecular scale. As requests for beam-time with this laser increases, SLAC is purposing a linac upgrade to better match this demand. This upgrade, named LCLS-II, will replace existing copper radio frequency …


Maximizing Precision Of Variable Star Photometry With Digital Cameras In Suburban Environments, David Hergesheimer Aug 2014

Maximizing Precision Of Variable Star Photometry With Digital Cameras In Suburban Environments, David Hergesheimer

STAR Program Research Presentations

Photometry is the measure of the brightness of an object. When making such measurements on stars, it is done is units of magnitude, which is on a logarithmic scale with a base of ~2.512. Variable star photometry using a commercially available digital camera is not going to be as accurate and precise as equipment used by astronomers, and because of the logarithmic scale of magnitude used, determining how much of an effect different error reduction strategies have is not straightforward, and is best done experimentally.

My research is conducting photometry on variable stars (changing brightness) with a digital camera, and …


Particle Image Velocimetry Of Transverse Jets In Crossflow, Jesse K. Tsai, Kayla Kuzmich, David Forliti, Kriss Vanderhyde, Nils Sedano Aug 2014

Particle Image Velocimetry Of Transverse Jets In Crossflow, Jesse K. Tsai, Kayla Kuzmich, David Forliti, Kriss Vanderhyde, Nils Sedano

STAR Program Research Presentations

The jet in crossflow (JICF) has been an ongoing study for the past several decades with applications in the field of fluid mechanics. This particular flow field produces vortical structures tied to the entrainment and mixing of two separate fluids. Research of the JICF seeks to determine a model and trajectory scaling law for future designs. This will help future designers to optimize the mixing and homogeneity of the two fluids to decrease emissions from pollutants, make ignition easier, and improve combustion efficiency of rockets.

Our experiment will employ Particle Image Velocimetry (PIV) to determine the fluid motion of the …


Tuffoam Density Variation Through Radiography, Sergio Contreras Esquivel Aug 2014

Tuffoam Density Variation Through Radiography, Sergio Contreras Esquivel

STAR Program Research Presentations

TufFoam is a low density, high impact tolerant polyurethane foam with good high voltage breakdown developed at the Sandia National Laboratories. Identically shaped samples have been produced with various formulations and production conditions. Eight different variables were studied. Our aim is to compare the density variation of the material when produced and processed under distinct conditions. The density of TufFoam is determined using radiographic imaging. We extract the foam density by fitting the radiographic density of each step in a plastic step wedge with 10 steps from 0.1 to 1.0 inches and applying the resulting equation to convert each pixel …


Exploring Soil Moisture Protocol Alternatives For The Classroom Setting, Garrett Smith Aug 2014

Exploring Soil Moisture Protocol Alternatives For The Classroom Setting, Garrett Smith

STAR Program Research Presentations

Climate change poses a direct threat to future water resources but current climate models suffer from uncertainties regarding the availability of regional water. SMAP or the Soil Moisture Active Passive mission seeks to make improvements to climate models by taking highly accurate, high resolution measurements of global soil moisture. To engage students around the world in a collection of meaningful data that may support the SMAP satellite mission, the Global Learning and Observations to Benefit the Environment program or GLOBE, has forged a partnership with NASA and JPL. GLOBE brings the power of citizen science to the SMAP mission, empowering …


Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner Aug 2014

Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner

STAR Program Research Presentations

Superamphiphobic surfaces strongly repel both water and oils. In this work, aluminum coupons are processed by sanding with various grit of sand paper to impart microscale roughness. Subsequent submersion of the aluminum substrate in boiling water grows nanoscale grass-like structures. The oxide layer of Al is slightly soluble in water. During a fast diffusion/equilibrium, Al2O3 nanograss grows on the surface. A low energy coating is then deposited on the surface. The micro and nanoscale features create re-entrant structures that trap air enabling contact liquid to be in a Cassie-Baxter state. Superamphiphobicity of the samples were confirmed by …


Characterization Of Polarized Synchrotron Light, Britny N. Delp, Jeff Corbett Jan 2014

Characterization Of Polarized Synchrotron Light, Britny N. Delp, Jeff Corbett

STAR Program Research Presentations

The Stanford Synchrotron Radiation Light accelerates electrons around a 234-meter circumference ring at relativistic speeds. The x-ray radiation produced by this process is used in many fields of science ranging from materials science to medicine.

This project seeks to measure the polarization of the 532 nanometer wavelength component in the visible light beam emitted from the SPEAR-3 synchrotron as a function of vertical position. The beam was focused through a lens, then passed through a 532 nm band pass filter and a polarizer mounted on a rotating stand. The beam power was measured as a function of vertical position and …


Evolution Of Perturbations In Flow Field Mechanics, Samantha R. Bell, David Forliti, Nils Sedano, Kriss Vanderhyde Jan 2014

Evolution Of Perturbations In Flow Field Mechanics, Samantha R. Bell, David Forliti, Nils Sedano, Kriss Vanderhyde

STAR Program Research Presentations

This project explores the stability analysis of a given flow field. Specifically, where the peak disturbance occurs in a flow as this is the disturbance that is most likely to occur. In rocket combustion, it is important to understand where the maximum disturbance occurs so that the mixing of fuel can be stabilized. The instabilities are the results of frequencies in the area surrounding the flow field. The linear stability governing equations are employed to better understand the disturbance. The governing equations for continuity and momentum in the x and y directions are used to form an equation for the …