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Photoproduction Of Π0 On Hydrogen With Clas From 1.1 Gev - 5.45 Gev Using E+E –Γ Decay, Michael C. Kunkel

Physics Theses & Dissertations

Photoproduction of the π⁰ meson was studied using the CLAS detector at the Thomas Jefferson National Accelerator Facility using tagged incident photon energies spanning the range E_γ = 1.1 GeV - 5.45 GeV. The measurement is performed on a liquid hydrogen target in the reaction γp → pe ⁺e^–(γ). The final state of the reaction is the sum of two subprocesses for π⁰ decay, the Dalitz decay mode of π⁰ → e ⁺e^–γ and conversion mode where one photon from π⁰ → γγ decay is converted into a …

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Ionizing Radiation Detection Using Microstructured Optical Fiber, Stanton Dehaven

Electrical & Computer Engineering Theses & Dissertations

Ionizing radiation detecting microstructured optical fibers are fabricated, modeled and experimentally measured for X-ray detection in the 10-40 keV energy range. These fibers operate by containing a scintillator material which emits visible light when exposed to ionizing radiation. An X-ray source characterized with a CdTe spectrometer is used to quantify the X-ray detection efficiency of the fibers. The solid state CdTe detector is considered 100% efficient in this energy range. A liquid filled microstructured optical fiber (MOF) is presented where numerical analysis and experimental observation leads to a geometric theory of photon transmission using total internal reflection. The model relates …

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X-Ray Structure, Thermodynamics, Elastic Properties And Mdsimulations Of Cardiolipin/Dimyristoylphosphatidylcholine Mixedmembranes, Alex Boscia, Bradley Treece, Dariush Mohammadyani, Judith Klein-Seetharaman, Anthony Braun, Beate Kloesgen, Tsjerk Wassenaar, Stephanie Tristram-Nagle

Prof. Stephanie Tristram-Nagle Ph.D.

tCardiolipins (CLs) are important biologically for their unique role in biomembranes that couple phos-phorylation and electron transport like bacterial plasma membranes, chromatophores, chloroplasts andmitochondria. CLs are often tightly coupled to proteins involved in oxidative phosphorylation. The firststep in understanding the interaction of CL with proteins is to obtain the pure CL structure, and the struc-ture of mixtures of CL with other lipids. In this work we use a variety of techniques to characterize the fluidphase structure, material properties and thermodynamics of mixtures of dimyristoylphosphatidylcholine(DMPC) with tetramyristoylcardiolipin (TMCL), both with 14-carbon chains, at several mole percentages.X-ray diffuse scattering was used to …

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Xena: An Automated 'Open-Source' 129xe Hyperpolarizer For Clinical Use, Panayiotis Nikolaou, Aaron M. Coffey, Laura L. Walkup, Brogan M. Gust, Nicholas Whiting, Hayley Newton, Iga Muradyan, Mikayel Dabaghyan, Kaili Ranta, Gregory D. Moroz, Matthew S. Rosen, Samuel Patz, Michael J. Barlow, Eduard Y. Chekmenev, Boyd M. Goodson

Nicholas Whiting

Here we provide a full report on the construction, components, and capabilities of our consortium’s “opensource”

large-scale (~1 L/h) 129Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The ‘hyperpolarizer’ is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800 Torr Xe in 0.5 L) in either stopped-flow or single-batch mode—making cryo-collection of the hyperpolarized gas unnecessary for many applications. …

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Name The Experiment! Interpreting Thermodynamic Derivatives As Thought Experiments, David Roundy, Mary Bridget Kustusch, Corrine Manogue

Mary Bridget Kustusch

We introduce a series of activities to help students understand the partial derivatives that arise in thermodynamics. Students construct thought experiments that would allow them to measure given partial derivatives. These activities are constructed with a number of learning goals in mind, beginning with helping students to learn to think of thermodynamic quantities in terms of how one can measure or change them. A second learning goal is for students to understand the importance of the quantities held fixed in either a partial derivative or an experiment. Students additionally are given an experimental perspective—particularly when this activity is combined with real laboratory experiments—on the meaning of either fixing …

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Partial Derivative Games In Thermodynamics: A Cognitive Task Analysis, Mary Bridget Kustusch, David Roundy, Corrine Manogue, Tevian Dray

Mary Bridget Kustusch

Several studies in recent years have demonstrated that upper-division students struggle with the

mathematics of thermodynamics. This paper presents a task analysis based on several expert attempts

to solve a challenging mathematics problem in thermodynamics. The purpose of this paper is twofold.

First, we highlight the importance of cognitive task analysis for understanding expert performance and

show how the epistemic games framework can be used as a tool for this type of analysis, with

thermodynamics as an example. Second, through this analysis, we identify several issues related to

thermodynamics that are relevant to future research into student understanding and learning …

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Recentering The Humanities, Mellon Grant For “Through The Looking Glass: The Science Of Art...Or The Art Of Science", Crystal Boyce, Karen Schmidt, Gabe Spalding

Crystal Boyce

This program proposes to bring together the disciplines of art, theatre, physics, and chemistry as represented through the works of Argonne scientists and how their discoveries have advanced the humanities.

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Characterization Of Large Area, Thick, And Segmented Silicon Detectors For Neutron Β-Decay Experiments, Americo Salas-Bacci, Patrick L. Mcgaughey, Stephan Baeßler, Leah Broussard, Mark F. Makela, J. Mirabal, Robert W. Pattie, Dinko Počanić, Sky K.L. Sjue, Seppo I. Penttila, Wesley S. Wilburn, Albert R. Young, B.A. Zeck, Zhehui Wang

Robert W. Pattie Jr.

The “Nab” and “UCNB” collaborations have proposed to measure the correlation parameters in neutron β-decay at Oak Ridge and Los Alamos National Laboratory, using a novel detector design. Two large area, thick, hexagonal-segmented silicon detectors containing 127 pixels per detector will be used to detect the proton and electron from neutron decay. Both silicon detectors are connected by magnetic field lines of a few Tesla field strength, and set on an electrostatic potential, such that protons can be accelerated up to 30 keV in order to be detected. Characteristics of the detector response to low energy conversion electrons and protons from …

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Standoff Methods For The Detection Of Threat Agents: A Review Of Several Promising Laser-Based Techniques, J. Bruce Johnson, Susan D. Allen, Jonathan Merten, Lewis Johnson, Daniel Pinkham, Scott Reeve

Scott Reeve

No abstract provided.

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Full-Text Articles in Physics

Photoproduction Of Π0 On Hydrogen With Clas From 1.1 Gev - 5.45 Gev Using E+E –Γ Decay, Michael C. Kunkel

Physics Theses & Dissertations

Ionizing Radiation Detection Using Microstructured Optical Fiber, Stanton Dehaven

Electrical & Computer Engineering Theses & Dissertations

X-Ray Structure, Thermodynamics, Elastic Properties And Mdsimulations Of Cardiolipin/Dimyristoylphosphatidylcholine Mixedmembranes, Alex Boscia, Bradley Treece, Dariush Mohammadyani, Judith Klein-Seetharaman, Anthony Braun, Beate Kloesgen, Tsjerk Wassenaar, Stephanie Tristram-Nagle

Prof. Stephanie Tristram-Nagle Ph.D.

Nicholas Whiting

Name The Experiment! Interpreting Thermodynamic Derivatives As Thought Experiments, David Roundy, Mary Bridget Kustusch, Corrine Manogue

Mary Bridget Kustusch

Partial Derivative Games In Thermodynamics: A Cognitive Task Analysis, Mary Bridget Kustusch, David Roundy, Corrine Manogue, Tevian Dray

Mary Bridget Kustusch

Recentering The Humanities, Mellon Grant For “Through The Looking Glass: The Science Of Art...Or The Art Of Science", Crystal Boyce, Karen Schmidt, Gabe Spalding

Crystal Boyce

Robert W. Pattie Jr.

Standoff Methods For The Detection Of Threat Agents: A Review Of Several Promising Laser-Based Techniques, J. Bruce Johnson, Susan D. Allen, Jonathan Merten, Lewis Johnson, Daniel Pinkham, Scott Reeve

Scott Reeve