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2024

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Diffusion Model Approach To Simulating Electron-Proton Scattering Events, Peter Devlin, Jian-Wei Qiu, Felix Ringer, Nobuo Sato Jan 2024

Diffusion Model Approach To Simulating Electron-Proton Scattering Events, Peter Devlin, Jian-Wei Qiu, Felix Ringer, Nobuo Sato

Physics Faculty Publications

Generative artificial intelligence is a fast-growing area of research offering various avenues for exploration in high-energy nuclear physics. In this work, we explore the use of generative models for simulating electron-proton collisions relevant to experiments like the Continuous Electron Beam Accelerator Facility and the future Electron-Ion Collider (EIC). These experiments play a critical role in advancing our understanding of nucleons and nuclei in terms of quark and gluon degrees of freedom. The use of generative models for simulating collider events faces several challenges such as the sparsity of the data, the presence of global or eventwide constraints, and steeply falling …

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Cebaf Injector At 200 Kv: K-Long Bunch Charge With Spin Flipper Off/On, Sunil Pokharel, Alicia Hofler, Reza Kazimi, Geoffrey Krafft, Max Bruker, Joe Grames, Riad Suleiman, Shukui Zhang Jan 2024

Cebaf Injector At 200 Kv: K-Long Bunch Charge With Spin Flipper Off/On, Sunil Pokharel, Alicia Hofler, Reza Kazimi, Geoffrey Krafft, Max Bruker, Joe Grames, Riad Suleiman, Shukui Zhang

Physics Faculty Publications

The forthcoming K-Long experiment in Jefferson Lab’s Hall D presents distinct beam requirements, marked by a notably low bunch repetition rate and an unusually high bunch charge. Furthermore, the Continuous Electron Beam Accelerator Facility (CEBAF) Injector requires a parity quality beam for experiments such as the Measurement of a Lepton-Lepton Electroweak Reaction (MOLLER). In this study, to prepare for the upcoming K-Long experiment, using the optimized settings of the magnetic elements and RF amplitude and phases, we conducted simulations covering a range of bunch charge beams, from low to high specifications, while considering concurrent operations across all four Halls at …

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Tmd Phenomenology With The Hso Approach, Tommaso Rainaldi, M. Boglione, J. O. Gonzalez-Hernandez, Ted C. Rogers Jan 2024

Tmd Phenomenology With The Hso Approach, Tommaso Rainaldi, M. Boglione, J. O. Gonzalez-Hernandez, Ted C. Rogers

Physics Faculty Publications

Transverse momentum dependent (TMD) observables are typically classified in terms of their contributions coming from different regions in transverse momentum. The low transverse momentum behavior is often ascribed to intrinsic nonperturbative properties of the hadron described by TMD factorization, while the large transverse momentum region can be computed using fixed order collinear perturbation theory. Combining both pictures in a consistent way presents challenges, for practical calculations as well as the interpretation of results. We discuss a recent approach that is designed to retain a physical interpretation in terms of hadron structure while alleviating tension with techniques used at much higher …

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Operation Of A Longitudinally Polarized Solid Nuclear Target Of Clas12, P. Pandey, J. Brock, T. Kageya, C. Keith, S. Kuhn, V. Lagerquist, J. Maxwell, X. Wei Jan 2024

Operation Of A Longitudinally Polarized Solid Nuclear Target Of Clas12, P. Pandey, J. Brock, T. Kageya, C. Keith, S. Kuhn, V. Lagerquist, J. Maxwell, X. Wei

Physics Faculty Publications

A suite of experiments measuring spin observables in electron-nucleon scattering (dubbed Run Group C) was recently executed in Jefferson Lab. These experiments involved the scattering of a polarized 11 GeV electron beam from longitudinally polarized nucleon targets located within the CLAS12 spectrometer in Hall B. The dynamically polarized target used in these experiments was designed and constructed exclusively for operation inside CLAS12 and further optimized for the requirements of Run Group C. We report on the complete target setup, operational experience with the target, the benchmarks achieved using various polarizable and unpolarized materials as well as the preliminary target polarization …

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1/Q² Power Corrections To Tmd Factorization For Drell-Yan Hadronic Tensor, I. Balitsky Jan 2024

1/Q² Power Corrections To Tmd Factorization For Drell-Yan Hadronic Tensor, I. Balitsky

Physics Faculty Publications

I calculate 1/Q2 power corrections to unpolarized Drell-Yan hadronic tensor for electromagnetic (EM) current at large N-c and demonstrate the EM gauge invariance at this level.

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Analytic Solutions Of The Dglap Evolution And Theoretical Uncertainties, A. Simonelli Jan 2024

Analytic Solutions Of The Dglap Evolution And Theoretical Uncertainties, A. Simonelli

Physics Faculty Publications

The energy dependence for the singlet sector of Parton Distributions Functions (PDFs) is described by an entangled pair of ordinary linear differential equations. Although there are no exact analytic solutions, it is possible to provide approximated results depending on the assumptions and the methodology adopted. These results differ in their sub-leading, neglected terms and ultimately they are associated with different treatments of the theoretical uncertainties. In this work, a novel analytic approach in Mellin space is presented and a new methodology for obtaining closed and exponentiated analytic solutions is devised. Different results for the DGLAP evolution at Next-Leading-Order are compared, …

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Inclusive Reactions From Finite Minkowski Spacetime Correlation Functions, Marco A. Carrillo, Raúl A. Briceño, Alexandru M. Sturzu Jan 2024

Inclusive Reactions From Finite Minkowski Spacetime Correlation Functions, Marco A. Carrillo, Raúl A. Briceño, Alexandru M. Sturzu

Physics Faculty Publications

The need to determine scattering amplitudes of few-hadron systems for arbitrary kinematics expands a broad set of subfields of modern-day nuclear and hadronic physics. In this work, we expand upon previous explorations on the use of real-time methods, like quantum computing or tensor networks, to determine few-body scattering amplitudes. Such calculations must be performed in a finite Minkowski spacetime, where scattering amplitudes are not well defined. Our previous work presented a conjecture of a systematically improvable estimator for scattering amplitudes constructed from finite-volume correlation functions. Here we provide further evidence that the prescription works for larger kinematic regions than previously …

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Solving The Homogeneous Bethe-Salpeter Equation With A Quantum Annealer, Filippo Fornetti, Alex Gnech, Tobias Frederico, Francesco Pederiva, Matteo Rinaldi, Alessandro Roggero, Giovanni Salmè, Sergio Scopetta, Michele Viviani Jan 2024

Solving The Homogeneous Bethe-Salpeter Equation With A Quantum Annealer, Filippo Fornetti, Alex Gnech, Tobias Frederico, Francesco Pederiva, Matteo Rinaldi, Alessandro Roggero, Giovanni Salmè, Sergio Scopetta, Michele Viviani

Physics Faculty Publications

The homogeneous Bethe-Salpeter equation (hBSE), describing a bound system in a genuinely relativistic quantum-field theory framework, was solved for the first time by using a D-Wave quantum annealer. After applying standard techniques of discretization, the hBSE, in ladder approximation, can be formally transformed in a generalized eigenvalue problem (GEVP), with two square matrices: one symmetric and the other nonsymmetric. The latter matrix poses the challenge of obtaining a suitable formal approach for investigating the nonsymmetric GEVP by means of a quantum annealer, i.e., to recast it as a quadratic unconstrained binary optimization problem. A broad numerical analysis of the proposed …

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The Continuous Electron Beam Accelerator Facility At 12 Gev, P. A. Adderly, S. Ahmed, T. Allison, R. Bachimanchi, K. Baggett, M. Bastaninejad, B. Bevins, M. Bevins, M. Bickley, R. M. Bodenstein, S. A. Bogacz, M. Bruker, A. Burrill, L. Cardman, J. Creel, Y. -C. Chao, G. Cheng, G. Ciovati, S. Chattopadhyay, Y. Zhang, Et Al. Jan 2024

The Continuous Electron Beam Accelerator Facility At 12 Gev, P. A. Adderly, S. Ahmed, T. Allison, R. Bachimanchi, K. Baggett, M. Bastaninejad, B. Bevins, M. Bevins, M. Bickley, R. M. Bodenstein, S. A. Bogacz, M. Bruker, A. Burrill, L. Cardman, J. Creel, Y. -C. Chao, G. Cheng, G. Ciovati, S. Chattopadhyay, Y. Zhang, Et Al.

Physics Faculty Publications

This review paper describes the energy-upgraded Continuous Electron Beam Accelerator Facility (CEBAF) accelerator. This superconducting linac has achieved 12 GeV beam energy by adding 11 new high-performance cryomodules containing 88 superconducting cavities that have operated cw at an average accelerating gradient of 20 MV/m. After reviewing the attributes and performance of the previous 6 GeV CEBAF accelerator, we discuss the upgraded CEBAF accelerator system in detail with particular attention paid to the new beam acceleration systems. In addition to doubling the acceleration in each linac, the upgrade included improving the beam recirculation magnets, adding more helium cooling capacity to …

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Rf And Mechanical Design Of A 915 Mhz Srf Cavity For Conduction-Cooled Cryomodules, G. Ciovati, A. Castilla-Loeza, G. Cheng, J. Henry, J. Rathke, J. Vennekate, K. Harding, T. Schultheiss, J. Lewis Jan 2024

Rf And Mechanical Design Of A 915 Mhz Srf Cavity For Conduction-Cooled Cryomodules, G. Ciovati, A. Castilla-Loeza, G. Cheng, J. Henry, J. Rathke, J. Vennekate, K. Harding, T. Schultheiss, J. Lewis

Physics Faculty Publications

Conduction-cooled SRF niobium cavities are being developed for use in compact, continuous-wave electron linear accelerators for a variety of industrial applications. A 915 MHz two-cell cavity has been designed to achieve an energy gain of 3.5 MeV. The design of the cell shape aims at minimizing the peak surface magnetic field. Field flatness is achieved by adjusting the length of the outer end half-cells. The higher-order mode analysis shows that absorbers are not required for a moderate beam current of 5 mA. One of the beam tubes has two side-ports for insertion of coaxial fundamental power couplers. The mechanical design …

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Towards Unpolarized Gpds From Pseudo-Distributions, Hervé Dutrieux, Robert G. Edwards, Colin Egerer, Joseph Karpie, Christopher Monahan, Kostas Orginos, Anatoly Radyushkin, David Richards, Eloy Romero, Savvas Zafeiropoulos Jan 2024

Towards Unpolarized Gpds From Pseudo-Distributions, Hervé Dutrieux, Robert G. Edwards, Colin Egerer, Joseph Karpie, Christopher Monahan, Kostas Orginos, Anatoly Radyushkin, David Richards, Eloy Romero, Savvas Zafeiropoulos

Physics Faculty Publications

We present an exploration of the unpolarized isovector proton generalized parton distributions (GPDs) Hu−d(x, ξ, t) and Eu−d(x, ξ, t) in the pseudo-distribution formalism using distillation. Taking advantage of the large kinematic coverage made possible by this approach, we present results on the moments of GPDs up to the order x3 — including their skewness dependence — at a pion mass mπ = 358 MeV and a lattice spacing a = 0.094 fm.

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Non-Symmetry In The Shock Refraction At A Closed Interface As A Recovery Mechanism, Anna Markhotok Jan 2024

Non-Symmetry In The Shock Refraction At A Closed Interface As A Recovery Mechanism, Anna Markhotok

Physics Faculty Publications

The possibility of a shock wave recovery at a discrete closed interface with a heated gas has been investigated. A two-dimensional model applied to conditions of optical discharges featuring spherical, elliptical, and drop-like configurations demonstrated that non-symmetry in the shock refraction contributes to the specific mechanism of recovery other than simply its compensation. Even though the full restoration of the hypersonic flow state does not occur in a strict sense of it, clear reverse changes toward the initial shape of the shock front eventually take place, thus creating an appearance of a full recovery seen in experiments. From analysis of …

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Conformal Bk Equation At Qcd Wilson-Fisher Point, I. Balitsky, G. A. Chirilli Jan 2024

Conformal Bk Equation At Qcd Wilson-Fisher Point, I. Balitsky, G. A. Chirilli

Physics Faculty Publications

High-energy scattering in pQCD in the Regge limit is described by the evolution of Wilson lines governed by the BK equation [1, 2]. In the leading order, the BK equation is conformally invariant and the eigenfunctions of the linearized BFKL equation are powers. It is a common belief that at d ≠ 4 the BFKL equation is useless since unlike d = 4 case it cannot be solved by usual methods. However, we demonstrate that at critical Wilson-Fisher point of QCD the relevant part of NLO BK restores the conformal invariance so the solutions are again powers. As a check …

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Dual-Energy Electron Storage Ring, B. Dhital, Y. S. Derbenev, A. Hutton, H. Zhang, G. A. Krafft, Y. Zhang, F. Lin, V. S. Morozov Jan 2024

Dual-Energy Electron Storage Ring, B. Dhital, Y. S. Derbenev, A. Hutton, H. Zhang, G. A. Krafft, Y. Zhang, F. Lin, V. S. Morozov

Physics Faculty Publications

A dual-energy electron storage ring is a novel concept initially proposed to cool hadron beams at high energies. The design consists of two closed rings operating at significantly different energies: the low-energy ring and the high-energy ring. These two rings are connected by an energy recovery linac (ERL) that provides the necessary energy difference. The ERL features superconducting radio-frequency (SRF) cavities that first accelerate the beam from the low energy EL to the high energy EH and then decelerate the beam from EH to EL in the next pass. The different SRF cavities in the ERL …

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Crabbing Cavity System Development For International Linear Collider, Subashini De Silva Jan 2024

Crabbing Cavity System Development For International Linear Collider, Subashini De Silva

Physics Faculty Publications

The International Liner Collider requires a crabbing system to increase the luminosity of the colliding electron bunches. The ILC has a large crossing angle that requires compensation in order to meet the luminosity requirements. There are several frequency options proposed for the crabbing cavity design. Two crab cavity designs were selected to be prototyped in the pre-lab phase, following the Down Selection Review on Crab Cavity Design held in April 2023. The two rf designs selected are the 1.3 GHz rf-dipole cavity and the 2.6 GHz QMiR cavity. We will be presenting the electromagnetic and mechanical design details of the …

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Proof Of Principle For A Self-Governing Prediction And Forecasting Reward Algorithm, Jose Osvaldo Gonzalez-Hernandez, Jonathan Marino, Ted Rogers, Brandon Velasco Jan 2024

Proof Of Principle For A Self-Governing Prediction And Forecasting Reward Algorithm, Jose Osvaldo Gonzalez-Hernandez, Jonathan Marino, Ted Rogers, Brandon Velasco

Physics Faculty Publications

We use Monte Carlo techniques to simulate an organized prediction competition between a group of scientific experts acting under the influence of a "self-governing" prediction reward algorithm. Our aim is to illustrate the advantages of a specific type of reward distribution rule that is designed to address some of the limitations of traditional forecast scoring rules. The primary extension of this algorithm as compared with standard forecast scoring is that it incorporates measures of both group consensus and question relevance directly into the reward distribution algorithm. Our model of the prediction competition includes parameters that control both the level of …

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Phenomenology Of Tmd Parton Distributions In Drell-Yan And Z⁰ Boson Production In A Hadron Structure Oriented Approach, F. Aslan, M. Boglione, J. O. Gonzalez-Hernandez, T. Rainaldi, T. C. Rogers, A. Simonelli Jan 2024

Phenomenology Of Tmd Parton Distributions In Drell-Yan And Z⁰ Boson Production In A Hadron Structure Oriented Approach, F. Aslan, M. Boglione, J. O. Gonzalez-Hernandez, T. Rainaldi, T. C. Rogers, A. Simonelli

Physics Faculty Publications

We present a first practical implementation of a recently proposed hadron structure oriented (HSO) approach to transverse momentum dependent (TMD) phenomenology applied to Drell-Yan-like processes, including lepton pair production at moderate Q² and Z⁰ boson production. We compare and contrast general features of our methodology with other common practices and emphasize aspects that we view as improvements. Separately, we discuss the importance of treatments that preserve various theoretical properties of the nonperturbative parts of TMD parametrizations for future applications that have the extraction of hadron structure as a primary goal. These include the HSO’s preservation of a basic TMD parton-model-like …

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Event Generators For High-Energy Physics Experiments, J. M. Campbell, M. Diefenthaler, T. J. Hobbs, S. Höche, J. Isaacson, F. Kling, S. Mrenna, J. Reuter, S. Alioli, J. R. Andersen, C. Andreaopoulos, A. M. Ankowski, E.C. Aschenauer, A. Ashkenazi, M. D. Baker, J. L. Barrow, M. Van Beekveld, G. Beswick, S. Bhattacharya, K. Zapp, Et Al. Jan 2024

Event Generators For High-Energy Physics Experiments, J. M. Campbell, M. Diefenthaler, T. J. Hobbs, S. Höche, J. Isaacson, F. Kling, S. Mrenna, J. Reuter, S. Alioli, J. R. Andersen, C. Andreaopoulos, A. M. Ankowski, E.C. Aschenauer, A. Ashkenazi, M. D. Baker, J. L. Barrow, M. Van Beekveld, G. Beswick, S. Bhattacharya, K. Zapp, Et Al.

Physics Faculty Publications

We provide an overview of the status of Monte-Carlo event generators for high-energy particle physics. Guided by the experimental needs and requirements, we highlight areas of active development, and opportunities for future improvements. Particular emphasis is given to physics models and algorithms that are employed across a variety of experiments. These common themes in event generator development lead to a more comprehensive understanding of physics at the highest energies and intensities, and allow models to be tested against a wealth of data that have been accumulated over the past decades. A cohesive approach to event generator development will allow these …

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F₀(1370) And F₀(980) Controversies From Dispersive Data Analyses, Jose R. Pelaez, A. Rodas, J. Ruiz De Elvira Jan 2024

F₀(1370) And F₀(980) Controversies From Dispersive Data Analyses, Jose R. Pelaez, A. Rodas, J. Ruiz De Elvira

Physics Faculty Publications

We report on our recent works on dispersive analyses of ππ → ππ and ππ → K ¯ K scattering data and their use to address two controversial aspects of the f₀(1370) and f₀(980) scalar mesons. First, we show with model-independent techniques that the f₀(1370) pole does indeed appear in meson–meson scattering data, although there is tension between its values in the ππ and K ¯ K channels. Second, we explain the proper interpretation of the f₀(980) pole residue, which would otherwise lead to branching ratios larger than one. We have also provided simple ππ → ππ data parameterizations that …

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Charge Lifetime Improvement Of The Continuous Electron Beam Accelerator Facility Photogun With A Biased Anode, J. T. Yoskowitz, G. A. Krafft, G. Palacios-Serrano, S.A.K. Wijethunga, J. Grames, J. Hansknecht, C. Hernandez-Garcia, M. Poelker, M. L. Stutzman, R. Suleiman, C. A. Valerio-Lizarraga, S. B. Van Der Geer Jan 2024

Charge Lifetime Improvement Of The Continuous Electron Beam Accelerator Facility Photogun With A Biased Anode, J. T. Yoskowitz, G. A. Krafft, G. Palacios-Serrano, S.A.K. Wijethunga, J. Grames, J. Hansknecht, C. Hernandez-Garcia, M. Poelker, M. L. Stutzman, R. Suleiman, C. A. Valerio-Lizarraga, S. B. Van Der Geer

Physics Faculty Publications

GaAs photocathodes in dc high-voltage photoguns are highly susceptible to ion back-bombardment, which reduces the photocathode quantum efficiency and limits the useful operating lifetime for producing polarized electron beams. This paper demonstrates that applying a small positive bias to the photogun anode can significantly suppress ion back-bombardment and increase charge lifetime. This technique was studied extensively using the Continuous Electron Beam Accelerator Facility photogun, where highly polarized electron beams created using a strained-superlattice GaAs/GaAsP photocathode were used and charge lifetimes improved by almost a factor of 2. A new simulation code ionator was developed to model ion production and tracking …

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Fully Relativistic Derivation Of The Thermal Sunyaev-Zel'dovich Effect, Balša Terzić, Geoffrey A. Krafft, William Clark, Alexandre Deur, Emerson Rogers, Ioannis Sakiotis, Brandon Velasco Jan 2024

Fully Relativistic Derivation Of The Thermal Sunyaev-Zel'dovich Effect, Balša Terzić, Geoffrey A. Krafft, William Clark, Alexandre Deur, Emerson Rogers, Ioannis Sakiotis, Brandon Velasco

Physics Faculty Publications

We present the first fully and inherently relativistic derivation of the thermal Sunyaev-Zel'dovich effect. This work uses the formalism historically applied to compute radiation spectra emerging from inverse Thomson/Compton sources of x-ray radiation. Comparing our results to the traditional approach based on relativistically-corrected classical Kompaneets equation, we find small, but systematic differences. Most notable are the modest (⩽10%) differences in the crossover frequency where the spectral distortion due to the Sunyaev-Zel'dovich effect vanishes, and the quadratic scaling of the energy shift with the electron cloud temperatures.

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New Spin Structure Constraints On Hyperfine Splitting And Proton Zemach Radius, David Ruth, Karl Slifer, Jian-Ping Chen, Carl E. Carlson, Franziska Hagelstein, Vladimir Pasculutsa, Alexandre Deur, Sebastian Kuhn, Marco Ripani, Xiaochao Zheng, Ryan Zielinski, Chao Gu Jan 2024

New Spin Structure Constraints On Hyperfine Splitting And Proton Zemach Radius, David Ruth, Karl Slifer, Jian-Ping Chen, Carl E. Carlson, Franziska Hagelstein, Vladimir Pasculutsa, Alexandre Deur, Sebastian Kuhn, Marco Ripani, Xiaochao Zheng, Ryan Zielinski, Chao Gu

Physics Faculty Publications

The 1S hyperfine splitting in hydrogen is measured to an impressive ppt precision and will soon be measured to ppm precision in muonic hydrogen. The latter measurement will rely on theoretical predictions, which are limited by knowledge of the proton polarizability effect Δpol. Data-driven evaluations of Δpol have long been in significant tension with baryon chiral perturbation theory. Here we present improved results for Δpol driven by new spin structure data, reducing the long-standing tension between theory and experiment and halving the dominating uncertainty in hyperfine splitting calculations.

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Coulomb Confinement In The Hamiltonian Limit, Sebastian M. Dawid, Wyatt A. Smith, Arkaitz Rodas, Robert J. Perry, César Fernández-Ramírez, Eric S. Swanson, Adam P. Szczepaniak Jan 2024

Coulomb Confinement In The Hamiltonian Limit, Sebastian M. Dawid, Wyatt A. Smith, Arkaitz Rodas, Robert J. Perry, César Fernández-Ramírez, Eric S. Swanson, Adam P. Szczepaniak

Physics Faculty Publications

The Gribov-Zwanziger scenario attributes the phenomenon of confinement to the instantaneous interaction term in the QCD Hamiltonian in the Coulomb gauge. For a static quark-antiquark pair, it leads to a potential energy that increases linearly with the distance between them. Lattice studies of the SU(2) Yang-Mills theory determined the corresponding (Coulomb) string tension for sources in the fundamental representation, 𝜎𝐶, to be about 3 times larger than the Wilson loop string tension, 𝜎𝐹. It is far above the Zwanziger variational bound, 𝜎𝐶 ≥𝜎𝐹. We argue that the value often reported in the literature …

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First Measurement Of Deeply Virtual Compton Scattering On The Neutron With Detection Of The Active Neutron, A. Hobart, S. Niccolai, M. Čuic, K. Kumerički, P. Achenbach, J. S. Alvarado, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, M. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, S. Boiarinov, M. Zurek, Et Al. Jan 2024

First Measurement Of Deeply Virtual Compton Scattering On The Neutron With Detection Of The Active Neutron, A. Hobart, S. Niccolai, M. Čuic, K. Kumerički, P. Achenbach, J. S. Alvarado, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, M. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, S. Boiarinov, M. Zurek, Et Al.

Physics Faculty Publications

Measuring deeply virtual Compton scattering (DVCS) on the neutron is one of the necessary steps to understand the structure of the nucleon in terms of generalized parton distributions (GPDs). Neutron targets play a complementary role to transversely polarized proton targets in the determination of the GPD 𝐸. This poorly known and poorly constrained GPD is essential to obtain the contribution of the quarks’ angular momentum to the spin of the nucleon. DVCS on the neutron was measured for the first time selecting the exclusive final state by detecting the neutron, using the Jefferson Lab longitudinally polarized electron beam, with energies …

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The Discharge-Induced Polarity-Dependent Propagation Characteristics Of A Strong Shock Wave, Anna Markhotok Jan 2024

The Discharge-Induced Polarity-Dependent Propagation Characteristics Of A Strong Shock Wave, Anna Markhotok

Physics Faculty Publications

The specifics of a shock wave propagation down a positive column of a DC discharge in molecular chemically inert gases has been investigated. It was shown that axial gradients caused by the imbalance in the charged particle momentum transfer to the gas molecules can be a reason for the shock velocity dependence on the electric field direction. In pure nitrogen gas, the calculated shock velocity difference of up to 13.5% is in good agreement with the 12% value obtained in the experiment. A returning gas flow organizing in the discharge as a possible mechanism for an extended shock structure and …

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Toward A Unified Description Of Hadron Scattering At All Energies, D. Stamen, D. Winney, A. Rodas, C. Fernandez-Ramirez, V. Mathieu, G. Montaña, A. Pilloni, A. P. Szczepaniak Jan 2024

Toward A Unified Description Of Hadron Scattering At All Energies, D. Stamen, D. Winney, A. Rodas, C. Fernandez-Ramirez, V. Mathieu, G. Montaña, A. Pilloni, A. P. Szczepaniak

Physics Faculty Publications

The construction of general amplitudes satisfying symmetries and 𝑆-matrix constraints has been the primary tool in studying the spectrum of hadrons for over half a century. In this work, we present a new parametrization, which can fulfill many expectations of 𝑆-matrix and Regge theory and connects the essential physics of hadron scattering in the resonance region and in asymptotic limits. In this construction, dynamical information is entirely contained in Regge trajectories that generalize resonance poles in the complex energy plane to moving poles in the angular momentum plane. We highlight the salient features of the model, compare with existing literature …

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Revisiting Gauge Invariance And Reggeization Of Pion Exchange, Glòria Montaña, Daniel Winney, Łukasz Bibrzycki, César Fernández-Ramirez, Giorgio Foti, Nadine Hammoud, Vincent Mathieu, Robert J. Perry, Alessandro Pilloni, Arkaitz Rodas, Vanamali Shastry, Wyatt A. Smith, Adam P. Szczepaniak Jan 2024

Revisiting Gauge Invariance And Reggeization Of Pion Exchange, Glòria Montaña, Daniel Winney, Łukasz Bibrzycki, César Fernández-Ramirez, Giorgio Foti, Nadine Hammoud, Vincent Mathieu, Robert J. Perry, Alessandro Pilloni, Arkaitz Rodas, Vanamali Shastry, Wyatt A. Smith, Adam P. Szczepaniak

Physics Faculty Publications

The Reggeized pion is expected to provide the main contribution to the forward cross section in light meson photoproduction reactions with charge exchange at high energies. We discuss the Reggeization of pion exchange in charged pion photoproduction with an emphasis on consistency with current conservation. We show that the gauge-invariant amplitude for the exchange of a particle with a generic even spin J ≥ 2 in the t channel is analytic at J = 0 and that it can be interpreted in terms of the nucleon electric current. This enables us to reconcile the dynamics in the s and u …

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Particle Accelerator Spin-Transparent Storage Rings For Beyond State-Of-The-Art Science, R. Suleiman, Y. Derbenev, M. Grau, V. Morozov Jan 2024

Particle Accelerator Spin-Transparent Storage Rings For Beyond State-Of-The-Art Science, R. Suleiman, Y. Derbenev, M. Grau, V. Morozov

Physics Faculty Publications

We will describe spin-transparent storage rings that exhibit spin-coherence times of several hours and store a large number of particles and their use in novel applications. For example, these rings can be used to directly measure the electric dipole moment of the electron, relevant to CP violation and matter-antimatter asymmetry in the universe, and to search for dark energy and ultra-light dark matter*. These rings can also serve as a compelling platform for quantum computing. In this presentation, we will describe how spin-transparent rings can be used in conjunction with ion traps to enhance scalability and increase quantum coherence times …

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Comparison Of Enhanced And Standard Data Sheets On Treatment Fidelity And Data Collection For Tact Training, Mary Halbur, Jessi Reidy, Tiffany Kodak, Landon Scott Cowan, Michael Harman Jan 2024

Comparison Of Enhanced And Standard Data Sheets On Treatment Fidelity And Data Collection For Tact Training, Mary Halbur, Jessi Reidy, Tiffany Kodak, Landon Scott Cowan, Michael Harman

Psychology Faculty Research and Publications

Specifically designed data sheets have been recommended to assist with the fidelity of implementation of treatment procedures. The present study extended previous research (e.g., Bottini et al. Behavior Analysis: Research & Practice 21(2), 140–152, 2021; LeBlanc et al. Behavior Analysis in Practice 13(1), 53–62, 2020) by comparing an enhanced data sheet (i.e., the inclusion of randomized targets, prompts for treatment components of securing attending and reinforcement) to a standard data sheet (i.e., targets not preset, no prompts for treatment components) on the fidelity of tact training of features. Ten behavior therapists participated in each condition (n = …

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Editorial: Insights In Neurocognitive Aging And Behavior: 2022, Kristy A. Nielson, Annalena Venneri, Shin Murakami Jan 2024

Editorial: Insights In Neurocognitive Aging And Behavior: 2022, Kristy A. Nielson, Annalena Venneri, Shin Murakami

Psychology Faculty Research and Publications

No abstract provided.

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