Physical Sciences and Mathematics Commons^™

K± Production In Semi-Inclusive Deep Inelastic Scattering Using Transversely Polarized Targets And The Solid Spectrometer, John Arrington, Whitney Armstrong, Paul Reimer, Seamus Riordan, Junqi Xie, Zhihong Ye, Andrew Puckett, Haiyan Gao, Chao Gu, Xiaqing Li, Weizhi Xiong, Zhiwen Zhao, Fatiha Benmokhtar, Alexandre Camsonne, Jian-Ping Chen, Tianbo Liu, Miha Mihovilovič, Simon Širca, Mitra Shabestari, Mohammad Hattawy, Garth Huber, Abhay Despande, Klaus Dehmelt, Nils Feege, Thomas Hemmick, Krishna Kumar, Sanghwa Park, Jinlong Zhang, Chendi Shen, Fuyue Wang, Yi Wang

Physics Faculty Publications

We propose to perform the measurement of K^± production in the Semi-Inclusive Deep Inelastic Scattering (SIDIS) using both the transversely polarized proton (NH₃) target and the transversely polarized ³He target (as effective polarized neutron target) on the SoLID spectrometer. This measurement will be carried out in parallel with the already approved SoLID spectrometer. This measurement will be carried out in parallel with the already approved SoLID experiments which will measure the π^± production in SIDIS, including E12-10-006 with transversely polarized ³He target and E12-11-108 with a transversely polarized NH₃ target. We will perform the off-line analysis to extract …

Parton Distribution Functions On The Lattice And In The Continuum, Joseph Karpie, Kostas Orginos, Anatoly Radyushkin, Savvas Zafeiropoulos

Physics Faculty Publications

Ioffe-time distributions, which are functions of the Ioffe-time ν, are the Fourier transforms of parton distribution functions with respect to the momentum fraction variable x. These distributions can be obtained from suitable equal time, quark bilinear hadronic matrix elements which can be calculated from first principles in lattice QCD, as it has been recently argued. In this talk I present the first numerical calculation of the Ioffe-time distributions of the nucleon in the quenched approximation.

First Test Results Of Superconducting Twin Axis Cavity For Erl Applications, Hyekyoung Park, Subashini De Silva, Jean R. Delayen, Andrew Hutton, Frank Marhauser

Physics Faculty Publications

RF superconducting (SRF) cavities with two beam pipes have been proposed in the past for energy recovery linac applications. The relatively complex geometry of those cavities presented a serious challenge for fabrication and surface processing. The main concerns have now been overcome with the fabrication and successful RF testing of a new elliptical twin-axis cavity proposed by Jefferson Lab (JLab) and optimized by the Center for Accelerator Science (CAS) at Old Dominion University (ODU) in the framework of a DoE accelerator stewardship program. The cavity design provides uniform accelerating or decelerating fields for both beams. This paper describes the cavity …

Study Of J/Ψ Photoproduction Off Deuteron, M. D. Baker, A. J. Freese, L. Guo, C. Hyde, Y. Ilieva, B. Mckinnon, P. Nadel-Turonski, M. Sargsian, V. Kubarovsky, S. Stepanyan, N. Zachariou, Z. W. Zhao

Physics Faculty Publications

Exclusive, near-threshold quasi-real photoproduction of J/ψ off the deuteron provides attractive opportunities to study interesting physics. Besides studying the gluonic structure of bound nucleons and the deuteron (in coherent production), studying the final-state interactions allows a direct access to the elementary J/ψN cross section. There is one measurement of the near-threshold quasi-elastic J/ψ production off the deuteron, however data on final-state interactions or of the coherent cross section do not exist. With its high luminosity and large acceptance, the CLAS12 detector is well suited to measure near-threshold photoproduction of J/ψ off the deuteron.

This is a proposal to measure the …

High Field Q Slope And The Effect Of Low-Temperature Baking At 3 Ghz, G. Ciovati, G. Eremeev, F. Hannon

Physics Faculty Publications

A strong degradation of the unloaded quality factor with field, called high field Q slope, is commonly observed above B_p ≅ 100 mT in elliptical superconducting niobium cavities at 1.3 and 1.5 GHz. In the present experiments several 3 GHz niobium cavities were measured up to and above B_p ≅ 100 mT. The measurements show that a high field Q slope phenomenon limits the field reach at this frequency, that the high field Q slope onset field depends weakly on the frequency, and that the high field Q slope can be removed by the typical empirical solution of …

Search For Three-Nucleon Short-Range Correlations In Light Nuclei, Z. Ye, P. Solvignon, D. Nguten, P. Aguilera, Z. Ahmed, H. Albataineh, K. Allada, B. Anderson, D. Anez, L. B. Weinstein

Physics Faculty Publications

We present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive ⁴He/³He cross section ratio is observed to be both x and Q² independent for 1.5 < x < 2, confirming the dominance of two-nucleon short-range correlations. For x > 2, our data support the hypothesis that a previous claim of three-nucleon correlation dominance was an artifact caused by the limited resolution of the measurement. While 3N-SRCs appear to have an important contribution, our data show that isolating 3N-SRCs is significantly more complicated than for 2N-SRCs.

Solutions For Fermi Questions, May 2018: Question 1: Throwing Out Energy; Question 2: Blood Pressure, Larry Weinstein

Physics Faculty Publications

The article provides answers to questions including the amount of energy wasted when Americans throw out unused ice from their drinks, and why blood pressure is measured on the upper arm.

Erosion In Extruder Flows: Analytical And Numerical Study, Miron Kaufman, Petru S. Fodor

Physics Faculty Publications

© 2017 Author(s). We consider the erosion of particles (e.g. carbonblack agglomerates) advected by the polymeric flow in a single screw extruder. We assume a particle to be made of primary fragments bound together. In the erosion process a primary fragment breaks out of a given particle. Particles disperse because of the shear stresses imparted by the fluid. The time evolution of the numbers of particles of different sizes is described by the Bateman coupled differential equations developed a century ago to model radioactivity. Using the particle size distribution we compute an entropic fragmentation index which varies from 0 for …

Measuring Polarized Emission In Clusters In The Cmb S4 Era, Louis Thibaut, Emory F. Bunn, Benjamin Wandelt, Joseph Silk

Physics Faculty Publications

The next generation of CMB experiments (CMB Stage-4) will produce a Sunyaev-Zel’dovich (SZ) cluster catalog containing ∼105 objects, two orders of magnitudes more than currently available. In this paper, we discuss the detectability of the polarized signal generated by scattering of the CMB quadrupole on the cluster electron gas using this catalog. We discuss the possibility of using this signal to measure the relationship between cluster optical depth and mass. We find that the area of observation of S4 maximizes the signal-to-noise (S/N) on the polarized signal but that this S/N is extremely small for an individual cluster, of order …

Endothelial Nitric Oxide Synthase Oxygenase On Lipid Nanodiscs: A Nano-Assembly Reflecting Native-Like Function Of Enos, Ghaith Altawallbeh, Mohammad M. Haque, Kiril A. Streletzky, Dennis J. Stuehr, Mekki Bayachou

Physics Faculty Publications

© 2017 Elsevier Inc. Endothelial nitric oxide synthase (eNOS) is a membrane-anchored enzyme. To highlight the potential role and effect of membrane phospholipids on the structure and activity of eNOS, we have incorporated the recombinant oxygenase subunit of eNOS into lipid nanodiscs. Two different size distribution modes were detected by multi-angle dynamic light scattering both for empty nanodiscs, and nanodiscs-bound eNOSoxy. The calculated hydrodynamic diameter for mode 1 species was 9.0 nm for empty nanodiscs and 9.8 nm for nanodisc bound eNOSoxy. Spectroscopic Griess assay was used to measure the enzymatic activity. Remarkably, the specific activity of nanodisc-bound eNOSoxy is …

Stabilization Of Hypoxia Inducible Factor By Cobalt Chloride Can Alter Renal Epithelial Transport, Subhra Nag, Andrew Resnick

Physics Faculty Publications

© 2017 The Authors. Given the importance of the transcriptional regulator hypoxia-inducible factor-1 (HIF-1) for adaptive hypoxia responses, we examined the effect of stabilized HIF-1α on renal epithelial permeability and directed sodium transport. This study was motivated by histological analysis of cystic kidneys showing increased expression levels of HIF-1α and HIF-2α. We hypothesize that compression induced localized ischemia-hypoxia of normal epithelia near a cyst leads to local stabilization of HIF-1α, leading to altered transepithelial transport that encourages cyst expansion. We found that stabilized HIF-1α alters both transcellular and paracellular transport through renal epithelial monolayers in a manner consistent with secretory …

Evaluation Of Wrf Scm Simulations Of Stratocumulus-Topped Marine And Coastal Boundary Layers And Improvements To Turbulence And Entrainment Parameterizations, Mohamed S. Ghonima, Handa Yang, Chang Ki Kim, Thijs Heus, Jan Kleissl

Physics Faculty Publications

© 2017. The Authors. Stratocumulus-topped boundary layers (STBLs) are notoriously difficult to parameterize in single-column models due to the strong inversion layer across which entrainment mixing plays an important role in modulating the boundary layer mass, energy, and moisture balances. We compare three different WRF planetary boundary layer (PBL) schemes (Yonsei University, YSU; Asymmetric Convective Model version 2, ACM2; Mellor-Yamada-Nakanishi-Niino, MYNN) against large eddy simulations (LES) to find out that they underestimate entrainment flux in stratocumulus over both ocean and coastal land. Hence, the PBL schemes produce a cooler, moister STBL with higher liquid water content. In order to improve …

A Glimpse Of Gluons Through Deeply Virtual Compton Scattering On The Proton, M. Defurne, A. Marti Jimenez-Arguello, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, M. N. H. Rashad

Physics Faculty Publications

The internal structure of nucleons (protons and neutrons) remains one of the greatest outstanding problems in modern nuclear physics. By scattering high-energy electrons off a proton we are able to resolve its fundamental constituents and probe their momenta and positions. Here we investigate the dynamics of quarks and gluons inside nucleons using deeply virtual Compton scattering (DVCS)-a highly virtual photon scatters off the proton, which subsequently radiates a photon. DVCS interferes with the Bethe-Heitler (BH) process, where the photon is emitted by the electron rather than the proton. We report herein the full determination of the BH-DVCS interference by exploiting …

Surface Impedance And Optimum Surface Resistance Of A Superconductor With An Imperfect Surface, Alex Gurevich, Takayuki Kubo

Physics Faculty Publications

We calculate a low-frequency surface impedance of a dirty, s-wave superconductor with an imperfect surface incorporating either a thin layer with a reduced pairing constant or a thin, proximity-coupled normal layer. Such structures model realistic surfaces of superconducting materials which can contain oxide layers, absorbed impurities, or nonstoichiometric composition. We solved the Usadel equations self-consistently and obtained spatial distributions of the order parameter and the quasiparticle density of states which then were used to calculate a low-frequency surface resistance R_s (T) and the magnetic penetration depth λ(T) as functions of temperature in the limit of local London electrodynamics. It …

First Exclusive Measurement Of Deeply Virtual Compton Scattering Off 4He: Toward The 3d Tomography Of Nuclei, M. Hattawy, N. A. Baltzell, R. Dupré, K. Hafidi, S. Stepanyan, S. Bültmann, R. De Vita, A. El Alaoui, L. El Fassi, H. Egiyan, B. Torayev, D. Adikaram, M. J. Amaryan, G. Charles, M. Khachatryan, A. Klein, S. E. Kuhn, M. Mayer, Y. Prok, L. B. Weinstein, Z. W. Zhao

Physics Faculty Publications

We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ⁴He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4 …}

Lattice Qcd Exploration Of Parton Pseudo-Distribution Functions, Kostas Orginos, Anatoly Radyushkin, Joseph Karpie, Savvas Zafeiropoulos

Physics Faculty Publications

We demonstrate a new method of extracting parton distributions from lattice calculations. The starting idea is to treat the generic equal-time matrix element M(Pz(3), z(3)(2)) as a function of the Ioffe time nu = Pz(3) and the distance z(3). The next step is to divide M(Pz(3), z(3)(2)) by the rest-frame density M(0, z(3)(2)). Our lattice calculation shows a linear exponential z(3)-dependence in the rest-frame function, expected from the Z(z(3)(2)) factor generated by the gauge link. Still, we observe that the ratio M (Pz(3), z(3)(2))/M(Pz(3), z(3)(2)) has a Gaussian-type behavior with respect to z(3) for 6 values of P used in …

Fermi Questions, Question 1: Trumpet Spit; Question 2: Tall Buildings, Larry Weinstein

Physics Faculty Publications

A quiz concerning physics is presented on topics such as the amount of saliva consumed by trumpeter Louis Armstrong during his career and the effect of buildings in the rotational inertia of the planet Earth.

Intercalation Of Si Between Mos2 Layers, Rik Van Bremen, Qirong Yao, Soumya Banerjee, Deniz Cakir, Nuri Oncel, Harold J.W. Zandvliet

Physics Faculty Publications

We report a combined experimental and theoretical study of the growth of sub-monolayer amounts of silicon (Si) on molybdenum disulfide (MoS2). At room temperature and low deposition rates we have found compelling evidence that the deposited Si atoms intercalate between the MoS2 layers. Our evidence relies on several experimental observations: (1) Upon the deposition of Si on pristine MoS2 the morphology of the surface transforms from a smooth surface to a hill-and-valley surface. The lattice constant of the hill-and-valley structure amounts to 3.16 Å, which is exactly the lattice constant of pristine MoS2. (2) The transitions from hills to valleys …

Pure E And B Polarization Maps Via Wiener Filtering, Emory F. Bunn, Benjamin Wandelt

Physics Faculty Publications

In order to draw scientific conclusions from observations of cosmic microwave background (CMB) polarization,it is necessary to separate the contributions of the E and B components of the data. For data with incomplete sky coverage, there are ambiguous modes, which can be sourced by either E or B signals. Techniques exist for producing “pure” E and B maps, which are guaranteed to be free of cross-contamination, although the standard method, which involves constructing an eigenbasis, has a high computational cost. We show that such pure maps can be thought of as resulting from the application of a Wiener filter to …

Microhh 1.0: A Computational Fluid Dynamics Code For Direct Numerical Simulation And Large-Eddy Simulation Of Atmospheric Boundary Layer Flows, Chiel C. Van Heerwaarden, Bart J.H. Van Stratum, Thijs Heus, Jeremy A. Gibbs, Evgeni Fedorovich, Juan Pedro Mellado

Physics Faculty Publications

© 2017 Author(s). This paper describes MicroHH 1.0, a new and open-source (www.microhh.org) computational fluid dynamics code for the simulation of turbulent flows in the atmosphere. It is primarily made for direct numerical simulation but also supports large-eddy simulation (LES). The paper covers the description of the governing equations, their numerical implementation, and the parameterizations included in the code. Furthermore, the paper presents the validation of the dynamical core in the form of convergence and conservation tests, and comparison of simulations of channel flows and slope flows against well-established test cases. The full numerical model, including the associated parameterizations for …

Angular Distribution Of Single-Photon Superradiance In A Dilute And Cold Atomic Ensemble, A. S. Kuraptsev, I. M. Sokolov, M. D. Havey

Physics Faculty Publications

On the basis of a quantum microscopic approach we study the dynamics of the afterglow of a dilute Gaussian atomic ensemble excited by pulsed radiation. Taking into account the vector nature of the electromagnetic field we analyze in detail the angular and polarization distribution of single-photon superradiance of such an ensemble. The dependence of the angular distribution of superradiance on the length of the pulse and its carrier frequency as well as on the size and the shape of the atomic clouds is studied. We show that there is substantial dependence of the superradiant emission on the polarization and the …

Exploring The Gender Gap In The Conceptual Survey Of Electricity And Magnetism, Rachel Henderson, Gay Stewart, John Stewart, Lynnette Michaluk, Adrienne L. Traxler

Physics Faculty Publications

The “gender gap” on various physics conceptual evaluations has been extensively studied. Men’s average pretest scores on the Force Concept Inventory and Force and Motion Conceptual Evaluation are 13% higher than women’s, and post-test scores are on average 12% higher than women’s. This study analyzed the gender differences within the Conceptual Survey of Electricity and Magnetism (CSEM) in which the gender gap has been less well studied and is less consistent. In the current study, data collected from 1407 students (77% men, 23% women) in a calculus-based physics course over ten semesters showed that male students outperformed female students on …

Higher-Twist Corrections To Gluon Tmd Factorization, I. Balitsky, A. Tarasov

Physics Faculty Publications

We calculate power corrections to TMD factorization for particle production by gluon-gluon fusion in hadron-hadron collisions.

Review Of Optical Detection Of Single Molecules Beyond The Diffraction And Diffusion Limit Using Plasmonic Nanostructures, Farzia Karim, Todd B. Smith, Chenglong Zhao

Physics Faculty Publications

Single-molecule detection has become a unique and indispensable tool for the study of molecular motions and interactions at the single-molecule level. Unlike ensemble measurement where the information is averaged, single-molecule analysis yields invaluable information on both the individual molecular properties and their microenvironment. Among the various technologies for the detection of single molecules, the detection with optical methods has many advantages in terms of its high sensitivity, electrical passiveness, and robustness. The recent advances in the engineering of either the excitation light or the solution of the molecules have paved the way for enhanced single-molecule detection. We present recent developments …

Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad

Physics Faculty Publications

We report the first longitudinal-transverse separation of the deeply virtual exclusive π⁰ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions dσ_L/dt, dσ_T/dt, dσ_LT/dt, and dσ_TT/dt are extracted as a function of the momentum transfer to the recoil system at Q² = 1.75 GeV² and x_B = 0.36. The ed -> edπ⁰ cross sections are found compatible with the small values expected from theoretical models. The en -> enπ⁰ cross sections show a dominance from the response to transversely polarized …

The Indianapolis Flux Experiment (Influx): A Test-Bed For Developing Urban Greenhouse Gas Emission Measurements, Kenneth J. Davis, Aijun Deng, Thomas Lauvaux, Natasha Miles, Scott Richardson, Daniel Sarmiento, Kevin R. Gurney, R Michael Hardesty, Timothy A. Bonin, W Alan Brewer, Brian K. Lamb, Paul B. Shepson, Rebecca M. Harvey, Maria Obiminda L. Cambaliza, Colm Sweeney, Jocelyn Turnbull, James Whetstone, Anna Karion

Physics Faculty Publications

The objective of the Indianapolis Flux Experiment (INFLUX) is to develop, evaluate and improve methods for measuring greenhouse gas (GHG) emissions from cities. INFLUX’s scientific objectives are to quantify CO2 and CH4 emission rates at 1 km2 resolution with a 10% or better accuracy and precision, to determine whole-city emissions with similar skill, and to achieve high (weekly or finer) temporal resolution at both spatial resolutions. The experiment employs atmospheric GHG measurements from both towers and aircraft, atmospheric transport observations and models, and activity-based inventory products to quantify urban GHG emissions. Multiple, independent methods for estimating urban emissions are a …

Electromagnetic Design Of A Superconducting Twin Axis Cavity, S. U. De Silva, H. Park, J. R. Delayen, F. Marhauser, A. Hutton

Physics Faculty Publications

The twin-axis cavity is a new kind of rf superconducting cavity that consists of two parallel beam pipes, which can accelerate or decelerate two spatially separated beams in the same cavity. This configuration is particularly effective for high-current beams with low-energy electrons that will be used for bunched beam cooling of high-energy protons or ions. The new cavity geometry was designed to create a uniform accelerating or decelerating fields for both beams by utilizing a TM₁₁₀ dipole mode. This paper presents the design rf optimization of a 1497 MHz twin-axis single-cell cavity, which is currently under fabrication.

Development Of A Superconducting Twin Axis Cavity, H. Park, F. Marhauser, A. Hutton, S. U. De Silva, J. R. Delayen

Physics Faculty Publications

Superconducting cavities with two separate accelerating axes have been proposed in the past for energy recovery linac applications. While the study showed the advantages of such cavity, the designs present serious fabrication challenges. Hence the proposed cavities have never been built. The new design, elliptical twin cavity, proposed by Jefferson Lab and optimized by Center for Accelerator Science at Old Dominion University, allows similar level of engineering and fabrication techniques of a typical elliptical cavity. This paper describes preliminary LOM and HOM spectrum, engineering and fabrication processes of the twin axis cavity.

Trim Tuning Of Sps-Series Dqw Crab Cavity Prototypes, S. Verdú-Andrés, J. Skaritka, Q. Wu, A. Ratti, S. Baurac, C. H. Boulware, T. Grimm, J. Yancey, W. Clemens, E. A. Mcewen, H. Park

Physics Faculty Publications

The final steps in the manufacturing of a superconducting RF cavity involve careful tuning before the final welds to match the target frequency as fabrication tolerances may introduce some frequency deviations. The target frequency is chosen based on analysis of the shifts induced by remaining processing steps including acid etching and cool down. The baseline fabrication of a DQW crab cavity for the High Luminosity LHC (HL-LHC) envisages a first tuning before the cavity subassemblies are welded together. To produce a very accurate final result, subassemblies are trimmed to frequency in the last machining steps, using a clamped cavity assembly …

Wakefield Analysis Of Superconducting Rf-Dipole Cavities, Subashini De Silva, Jean Delayen

Physics Faculty Publications

RF-dipole crabbing cavities are being considered for a variety of crabbing applications. Some of the applications are the crabbing cavity systems for LHC High Luminosity Upgrade and the proposed Electron-Ion Collider for Jefferson Lab. The design requirements in the current applications require the cavities to incorporate complex damping schemes to suppress the higher order modes that may be excited by the high intensity proton or electron beams traversing through the cavities. The number of cavities required to achieve the desired high transverse voltage, and the complexity in the cavity geometries also contributes to the wakefields generated by beams. This paper …