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Physics Faculty Publications

2020

Articles 1 - 30 of 52

Full-Text Articles in Physics

Parton Distribution Functions From Ioffe Time Pseudodistributions From Lattice Calculations: Approaching The Physical Point, Bálint Joó, Joseph Karpie, Kostas Orginos, Anatoly V. Radyushkin, David G. Richards, Savvas Zafeiropoulos Dec 2020

Parton Distribution Functions From Ioffe Time Pseudodistributions From Lattice Calculations: Approaching The Physical Point, Bálint Joó, Joseph Karpie, Kostas Orginos, Anatoly V. Radyushkin, David G. Richards, Savvas Zafeiropoulos

Physics Faculty Publications

We present results for the unpolarized parton distribution function of the nucleon computed in lattice QCD at the physical pion mass. This is the first study of its kind employing the method of Ioffe time pseudodistributions. Beyond the reconstruction of the Bjorken-x dependence, we also extract the lowest moments of the distribution function using the small Ioffe time expansion of the Ioffe time pseudodistribution. We compare our findings with the pertinent phenomenological determinations.

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A Climatological Analysis Of The Monsoon Break Following The Summer Monsoon Onset Over Luzon Island, Philippines, Lyndon Mark P. Olaguera, Jun Matsumoto, Hisayuki Kubota, Esperanza O. Cayanan, Flaviana D. Hilario Nov 2020

A Climatological Analysis Of The Monsoon Break Following The Summer Monsoon Onset Over Luzon Island, Philippines, Lyndon Mark P. Olaguera, Jun Matsumoto, Hisayuki Kubota, Esperanza O. Cayanan, Flaviana D. Hilario

Physics Faculty Publications

This study investigates the climatology of the monsoon break following the onset of the summer rainy season over Luzon Island (120–122.5°E, 13–22°N) in the Philippines from 1979–2017. The first post-onset monsoon break is remarkable in stations located over the north and central Luzon Island and occurs climatologically in early June. Composite analysis of the large-scale circulation features during the monsoon break period shows that this break is associated with the westward extension of the western North Pacific Subtropical High (WNPSH), which weakened the monsoon southwesterlies and induced enhanced low-level divergence over Luzon Island. The westward extension of the WNPSH may …

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Analogy Between Thermodynamic Phase Transitions And Creeping Flows In Rectangular Cavities, Miron Kaufman, Petru S. Fodor Nov 2020

Analogy Between Thermodynamic Phase Transitions And Creeping Flows In Rectangular Cavities, Miron Kaufman, Petru S. Fodor

Physics Faculty Publications

© 2020, MDPI AG. All rights reserved. An analogy is found between the streamline function corresponding to Stokes flows in rectangular cavities and the thermodynamics of phase transitions and critical points. In a rectangular cavity flow, with no-slip boundary conditions at the walls, the corners are fixed points. The corners defined by a stationary and a moving wall, are found to be analogous to a thermodynamic first-order transition point. In contrast, the corners defined by two stationary walls correspond to thermodynamic critical points. Here, flow structures, also known as Moffatt eddies, form and act as stagnation regions where mixing is …

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Size Dependence In Chord Characteristics From Simulated And Observed Continental Shallow Cumulus, Philipp J. Griewank, Thijs Heus, Neil P. Lareau, Roel A. J. Neggers Sep 2020

Size Dependence In Chord Characteristics From Simulated And Observed Continental Shallow Cumulus, Philipp J. Griewank, Thijs Heus, Neil P. Lareau, Roel A. J. Neggers

Physics Faculty Publications

© 2020 American Institute of Physics Inc.. All rights reserved. In this study we compare long-Term Doppler and Raman lidar observations against a full month of large eddy simulations of continental shallow cumulus clouds. The goal is to evaluate if the simulations can reproduce the mean observed vertical velocity and moisture structure of cumulus clouds and their associated subcloud circulations, as well as to establish if these properties depend on the size of the cloud.We propose methods to compare continuous chords of cloud detected from Doppler and Raman lidars with equivalent chords derived from 1D and 3D model output. While …

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Multi-Metallic Conduction Cooled Superconducting Radio-Frequency Cavity With High Thermal Stability, Gianluigi Ciovati, Gary Cheng, Uttar Pudasaini, Robert A. Rimmer Jul 2020

Multi-Metallic Conduction Cooled Superconducting Radio-Frequency Cavity With High Thermal Stability, Gianluigi Ciovati, Gary Cheng, Uttar Pudasaini, Robert A. Rimmer

Physics Faculty Publications

Superconducting radio-frequency cavities are commonly used in modern particle accelerators for applied and fundamental research. Such cavities are typically made of high-purity, bulk Nb and with cooling by a liquid helium bath at a temperature of ∼2 K. The size, cost and complexity of operating a particle accelerator with a liquid helium refrigerator make the current cavity technology not favorable for use in industrial-type accelerators. We have developed a multi-metallic 1.495 GHz elliptical cavity conductively cooled by a cryocooler. The cavity has a ∼2 μm thick layer of Nb3Sn on the inner surface, exposed to the rf field, …

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Characterizing Plasma With Emission Tomography-Feasibility Study On Synthetic And Experimental Data, M. Nikolić, A. Samolov, A. Godunov, L. Vušković,, S. Popović May 2020

Characterizing Plasma With Emission Tomography-Feasibility Study On Synthetic And Experimental Data, M. Nikolić, A. Samolov, A. Godunov, L. Vušković,, S. Popović

Physics Faculty Publications

We present a feasibility study on different tomographic algorithms to overcome the issues of finite sets of projection data, limited viewing angles, and noisy data, which cause the tomographic reconstruction to be an ill-posed inversion problem. We investigated three approaches: single angle Abel inversion, two angle approach, and multiple angle 2D plasma tomography. These methods were tested on symmetric and asymmetric sample functions and on experimental results from a supersonic flowing argon microwave plasma sustained in a cylindrical quartz cavity. The analysis focused on the afterglow region of the microwave flow where a plasmoid-like formation was observed. We investigated the …

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Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura May 2020

Consistency Checks For Two-Body Finite-Volume Matrix Elements. Ii. Perturbative Systems, Raúl A. Briceño, Maxwell T. Hansen, Andrew W. Jackura

Physics Faculty Publications

Using the general formalism presented in [Phys. Rev. D 94, 013008 (2016); Phys. Rev. D 100, 034511 (2019)], we study the finite-volume effects for the 2 þ J → 2 matrix element of an external current coupled to a two-particle state of identical scalars with perturbative interactions. Working in a finite cubic volume with periodicity L, we derive a 1=L expansion of the matrix element through O(1=L5) and find that it is governed by two universal current-dependent parameters, the scalar charge and the threshold two particle form factor. We confirm the result through a numerical study of the …

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Dynamics Of Subsiding Shells In Actively Growing Clouds With Vertical Updrafts, Vishnu Nair, Thijs Heus, Maarten Van Reeuwijk Apr 2020

Dynamics Of Subsiding Shells In Actively Growing Clouds With Vertical Updrafts, Vishnu Nair, Thijs Heus, Maarten Van Reeuwijk

Physics Faculty Publications

© 2020 American Meteorological Society. The dynamics of a subsiding shell at the edges of actively growing shallow cumulus clouds with updrafts is analyzed using direct numerical simulation. The actively growing clouds have a fixed in-cloud buoyancy and velocity. Turbulent mixing and evaporative cooling at the cloud edges generate a subsiding shell that grows with time. A self-similar regime is observed for first-and second-order moments when normalized with respective maximum values. Internal scales derived from integral properties of the flow problem are identified. A self-similarity analysis using these scales reveals that contrary to classical self-similar flows, the turbulent kinetic energy …

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The Clas12 Software Framework And Event Reconstruction, V. Ziegler, N. A. Baltzell, F. Bossù, D. S. Carman, P. Chatanon, M. Contalbrigo, J. Newton, M. Ungaro Apr 2020

The Clas12 Software Framework And Event Reconstruction, V. Ziegler, N. A. Baltzell, F. Bossù, D. S. Carman, P. Chatanon, M. Contalbrigo, J. Newton, M. Ungaro

Physics Faculty Publications

We describe offline event reconstruction for the CEBAF Large Acceptance Spectrometer at 12 GeV (CLAS12), including an overview of the offline reconstruction framework and software tools, a description of the algorithms developed for the individual detector subsystems, and the overall approach for charged and neutral particle identification. We also present the scheme for data processing and the code management procedures.

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Primary Cilia Have A Length-Dependent Persistence Length, Justin Flaherty, Zhe Feng, Zhangli Peng, Y. N. Young, Andrew Resnick Apr 2020

Primary Cilia Have A Length-Dependent Persistence Length, Justin Flaherty, Zhe Feng, Zhangli Peng, Y. N. Young, Andrew Resnick

Physics Faculty Publications

© 2019, The Author(s). The fluctuating position of an optically trapped cilium tip under untreated and Taxol-treated conditions was used to characterize mechanical properties of the cilium axoneme and its basal body by combining experimental, analytical,and computational tools. We provide, for the first time, evidence that the persistence length of a ciliary axoneme is length-dependent; longer cilia are stiffer than shorter cilia. We demonstrate that this apparent length dependence can be understood by a combination of modeling axonemal microtubules as anisotropic elastic shells and including actomyosin-driven stochastic basal body motion.Our results also demonstrate the possibility of using observable ciliary dynamics …

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Heavy Quark Expansion For Heavy-Light Light-Cone Operators, Shuai Zhao Apr 2020

Heavy Quark Expansion For Heavy-Light Light-Cone Operators, Shuai Zhao

Physics Faculty Publications

We generalize the celebrated heavy quark expansion to nonlocal QCD operators. By taking nonlocal heavy-light current on the light-cone as an example, we confirm that the collinear singularities are common between QCD operator and the corresponding operator in heavy quark effective theory (HQET), at the leading power of 1/M expansion. Based on a perturbative calculation in operator form at one-loop level, a factorization formula linking QCD and HQET operators is investigated and the matching coefficient is determined. The matching between QCD and HQET light-cone distribution amplitudes (LCDAs) as well as other momentum distributions of hadron can be derived as …

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Sociophysics Analysis Of Multi-Group Conflicts, Miron Kaufman, Hung T. Diep, Sanda Kaufman Feb 2020

Sociophysics Analysis Of Multi-Group Conflicts, Miron Kaufman, Hung T. Diep, Sanda Kaufman

Physics Faculty Publications

© 2020 by the authors. We present our research on the application of statistical physics techniques to multi-group social conflicts. We identify real conflict situations of which the characteristics correspond to the model. We offer realistic assumptions about conflict behaviors that get factored into model-generated scenarios. The scenarios can inform conflict research and strategies for conflict management. We discuss model applications to two-and three-group conflicts. We identify chaotic time evolution of mean attitudes and the occurrence of strange attractors. We examine the role that the range of interactions plays with respect to the occurrence of chaotic behavior.

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Non-Tropical Cyclone Related Winter Heavy Rainfall Events Over The Philippines: Climatology And Mechanisms, Lyndon Mark Olaguera, Jun Matsumoto, Julie Mae Dado, Gemma T. Narisma Jan 2020

Non-Tropical Cyclone Related Winter Heavy Rainfall Events Over The Philippines: Climatology And Mechanisms, Lyndon Mark Olaguera, Jun Matsumoto, Julie Mae Dado, Gemma T. Narisma

Physics Faculty Publications

This study investigates non-tropical cyclone (TC) related boreal winter heavy rainfall events that lead to extensive flooding (HRF) over the Philippines through a case study and composite analysis. The HRF event examined occurred during January 16–22, 2017 over Cagayan de Oro City (CDO) in Mindanao Island (122–127°E, 5–10°N). The accumulated rainfall over CDO reached by about 180 mm from 00 UTC January 16 to 00 UTC January 17, 2017, exceeding the climatological maximum daily rainfall in January over this area. The interaction of a westward propagating cyclonic circulation over Mindanao Island (MCC) and a shearline that is associated with an …

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First Measurement Of Direct Photoproduction Of The A2(1320)⁰ Meson On The Proton, K.P. Adhikari, M. J. Amaryan, D. Bullumulla, F. Hauenstein, M. Khachatryan, Y. Prok, Et Al., Clas Collaboration Jan 2020

First Measurement Of Direct Photoproduction Of The A2(1320)⁰ Meson On The Proton, K.P. Adhikari, M. J. Amaryan, D. Bullumulla, F. Hauenstein, M. Khachatryan, Y. Prok, Et Al., Clas Collaboration

Physics Faculty Publications

We present the first measurement of the reaction 𝛾p -> a₂(1320)⁰ p in the photon energy range 3.5-5.5 GeV and four-momentum transfer squared 0.2 < -t < 2.0 GeV2. Data were collected with the CEBAF Large Acceptance Spectrometer detector at the Thomas Jefferson National Accelerator Facility. The a2resonance was detected by measuring the reaction 𝛾p → π0ηp and reconstructing the π0η invariant mass. The most prominent feature of the differential cross section is a dip at -t ≈ 0.55 GeV2. This can be described in the framework of Regge phenomenology, where the exchange degeneracy hypothesis …

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Flux Expulsion In Niobium Superconducting Radio-Frequency Cavities Of Different Purity And Essential Contributions To The Flux Sensitivity, P. Dhakal, Gianluigi Ciovati, Alex Gurevich Jan 2020

Flux Expulsion In Niobium Superconducting Radio-Frequency Cavities Of Different Purity And Essential Contributions To The Flux Sensitivity, P. Dhakal, Gianluigi Ciovati, Alex Gurevich

Physics Faculty Publications

Magnetic flux trapped during the cooldown of superconducting radio-frequency cavities through the transition temperature due to incomplete Meissner state is known to be a significant source of radio-frequency losses. The sensitivity of flux trapping depends on the distribution and the type of defects and impurities which pin vortices, as well as the cooldown dynamics when the cavity transitions from a normal to superconducting state. Here we present the results of measurements of the flux trapping sensitivity on 1.3 GHz elliptical cavities made from large-grain niobium with different purity for different cooldown dynamics and surface treatments. The results show that lower …

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High-Luminosity Large Hadron Collider (Hl-Lhc): Technical Design Report, O. Aberle, C. Adorisio, A. Adraktas, M. Ady, J. Albertone, L. Alberty, M. Alcaide Leon, A. Alekou, D. Alesini, B. Almeida Ferreira, P. Alvarez-Lopez, G. Ambrosio, P. Andreu Munoz, M. Anerella, D. Angal-Kalinin, F. Antoniou, G. Apollinari, A. Apollonio, R. Appleby, I. Béjar Alonso, Jean Delayen, I. Zurbano Fernandez, Et Al., I. Béjar Alonso (Ed.), O. Brüning (Ed.), P. Fessia (Ed.), M. Lamont (Ed.), L. Rossi (Ed.), L. Tavian (Ed.), M. Zerlauth (Ed.) Jan 2020

High-Luminosity Large Hadron Collider (Hl-Lhc): Technical Design Report, O. Aberle, C. Adorisio, A. Adraktas, M. Ady, J. Albertone, L. Alberty, M. Alcaide Leon, A. Alekou, D. Alesini, B. Almeida Ferreira, P. Alvarez-Lopez, G. Ambrosio, P. Andreu Munoz, M. Anerella, D. Angal-Kalinin, F. Antoniou, G. Apollinari, A. Apollonio, R. Appleby, I. Béjar Alonso, Jean Delayen, I. Zurbano Fernandez, Et Al., I. Béjar Alonso (Ed.), O. Brüning (Ed.), P. Fessia (Ed.), M. Lamont (Ed.), L. Rossi (Ed.), L. Tavian (Ed.), M. Zerlauth (Ed.)

Physics Faculty Publications

The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered a global user community of about 9000 scientists working in fundamental particle physics and the physics of hadronic matter at extreme temperature and density. To sustain and extend its discovery potential, the LHC will need a major upgrade in the 2020s. This will increase its instantaneous luminosity (rate of collisions) by a factor of five beyond the original design value and the integrated luminosity (total number of collisions) by a factor ten. …

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Improving Inverse Compton Sources By Avoiding Non-Linearities, B. Terzić, G. A. Krafft, V. Petrillo, I. Drebot, M. Ruijter Jan 2020

Improving Inverse Compton Sources By Avoiding Non-Linearities, B. Terzić, G. A. Krafft, V. Petrillo, I. Drebot, M. Ruijter

Physics Faculty Publications

We present a new, more nuanced understanding of non-linear effects in inverse Compton sources. Deleterious non-linear effects can arise even at low laser intensities, a regime previously viewed as linear. After laying out a survey of non-linear phenomena which degrade the effectiveness of inverse Compton sources, we discuss two powerful techniques designed to avoid these non-linearities. Starting with the known technique of non-linear longitudinal chirping of the laser pulse in the high laser field regime, we show that the simple stretching of the laser pulse, while keeping the energy constant, can significantly increase the spectral density of the scattered radiation …

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Question 1: Car Flip; Question 2: A Mole Of People, Larry Weinstein Jan 2020

Question 1: Car Flip; Question 2: A Mole Of People, Larry Weinstein

Physics Faculty Publications

Consider mass, area, power, and food requirements. For more Fermi questions and answers, see Guesstimation 2.0: Solving Today's Problems on the Back of a Napkin, by Lawrence Weinstein (Princeton University Press, 2012). [Extracted from artcle]

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Solutions For Fermi Questions, January 2020: Question 1: Car Flip; Question 2: A Mole Of People, Larry Weinstein Jan 2020

Solutions For Fermi Questions, January 2020: Question 1: Car Flip; Question 2: A Mole Of People, Larry Weinstein

Physics Faculty Publications

At what speed will a car flip over when it slides side-ways into a curb? The angular momentum of the car will depend on its initial speed, the height of the curb, and the height of the center-of-mass (CM) of the car. If we approximate the car as having all its mass located at its CM, then its initial angular momentum relative to the top of the curb is. [Extracted from the article]

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Question 1: Plowing Snow; Question 2: Wasted Food, Larry Weinstein Jan 2020

Question 1: Plowing Snow; Question 2: Wasted Food, Larry Weinstein

Physics Faculty Publications

[Extracted from the article] How much snow is shoveled or plowed in the U.S. in a typical winter? How much food is wasted at school cafeterias every year in the U.S.? For more Fermi questions and answers, see Guesstimation 2.0: Solving Today's Problems on the Back of a Napkin, by Lawrence Weinstein (Princeton University Press, 2012).

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Optical-Depth Scaling Of Light Scattering From A Dense And Cold Atomic 87Rb Gas, K. J. Kemp, S. J. Roof, M. D. Havey, I. M. Sokolov, D. V. Kupriyanov, W. Guerin Jan 2020

Optical-Depth Scaling Of Light Scattering From A Dense And Cold Atomic 87Rb Gas, K. J. Kemp, S. J. Roof, M. D. Havey, I. M. Sokolov, D. V. Kupriyanov, W. Guerin

Physics Faculty Publications

We report investigation of near-resonance light scattering from a cold and dense atomic gas of 87Rb atoms. Measurements are made for probe frequencies tuned near the F=2→ F'=3 nearly closed hyperfine transition, with particular attention paid to the dependence of the scattered light intensity on detuning from resonance, the number of atoms in the sample, and atomic sample size. We find that, over a wide range of experimental variables, the optical depth of the atomic sample serves as an effective single scaling parameter which describes well all the experimental data.

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Neutron Valence Structure From Nuclear Deep Inelastic Scattering, E. P. Segarra, A. Schmidt, T. Kutz, D. W. Higinbotham, E. Piasetzky, M. Strikman, L. B. Weinstein, O. Hen Jan 2020

Neutron Valence Structure From Nuclear Deep Inelastic Scattering, E. P. Segarra, A. Schmidt, T. Kutz, D. W. Higinbotham, E. Piasetzky, M. Strikman, L. B. Weinstein, O. Hen

Physics Faculty Publications

Mechanisms of spin-flavor SU(6) symmetry breaking in quantum chromodynamics (QCD) are studied via an extraction of the free neutron structure function from a global analysis of deep inelastic scattering (DIS) data on the proton and on nuclei from A = 2 (deuterium) to 208 (lead). Modification of the structure function of nucleons bound in atomic nuclei (known as the EMC effect) are consistently accounted for within the framework of a universal modification of nucleons in short-range correlated (SRC) pairs. Our extracted neutron-to-proton structure function ratio Fn2/Fp2 becomes constant for xB ≥ 0.6, equaling 0.47 …

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Electron Tunneling And X-Ray Photoelectron Spectoscopy Studies Of The Superconductiong Properties Of Nitrogen-Doped Niobium Resonator Cavities, Eric M. Lechner, Basu Dev Oli, Junki Makita, Gianluigi Ciovati, Alex Gurevich, Maria Iavarone Jan 2020

Electron Tunneling And X-Ray Photoelectron Spectoscopy Studies Of The Superconductiong Properties Of Nitrogen-Doped Niobium Resonator Cavities, Eric M. Lechner, Basu Dev Oli, Junki Makita, Gianluigi Ciovati, Alex Gurevich, Maria Iavarone

Physics Faculty Publications

We use scanning tunneling microscopy (STM) and spectroscopy (STS), and x-ray photoelectron spectroscopy (XPS) to investigate the effect of nitrogen doping on the surface electronic and chemical structures of cutouts from superconducting Nb radio-frequency cavities. The goal of this work is to get insights into the fundamental physics and materials mechanisms behind the striking decrease of the surface resistance with the radio-frequency magnetic field, which has been observed on N-doped Nb cavities. Our XPS measurements reveal significantly more oxidized Nb 3d states and a thinner metallic suboxide layer on the N-doped Nb surfaces, which is also confirmed by tunneling spectroscopy …

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Nonlinear Dynamics And Dissipation Of A Curvilinear Vortex Driven By A Strong Time-Dependent Meissner Current, W.P.M.R. Pathirana, A. Gurevich Jan 2020

Nonlinear Dynamics And Dissipation Of A Curvilinear Vortex Driven By A Strong Time-Dependent Meissner Current, W.P.M.R. Pathirana, A. Gurevich

Physics Faculty Publications

We report numerical simulations of large-amplitude oscillations of a trapped vortex line under a strong ac magnetic field H(t)=H sinωt parallel to the surface. The power dissipated by an oscillating vortex segment driven by the surface ac Meissner currents was calculated by taking into account the nonlinear vortex line tension, vortex mass, and a nonlinear Larkin-Ovchinnikov (LO) viscous drag coefficient η(v). We show that the LO decrease of η(v) with the vortex velocity v can radically change the field dependence of the surface resistance Ri(H) caused by trapped vortices. At low frequencies, …

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Quasielastic Lepton Scattering And Back-To-Back Nucleons In The Short-Time Approximation, S. Pastore, J. Carlson, S. Gandolfi, R. Schiavilla, R. B. Wiringa Jan 2020

Quasielastic Lepton Scattering And Back-To-Back Nucleons In The Short-Time Approximation, S. Pastore, J. Carlson, S. Gandolfi, R. Schiavilla, R. B. Wiringa

Physics Faculty Publications

Understanding quasielastic electron and neutrino scattering from nuclei has taken on new urgency with current and planned neutrino oscillation experiments, and with electron scattering experiments measuring specific final states, such as those involving nucleon pairs in "back-to-back" configurations. Accurate many-body methods are available for calculating the response of light (A <= 12) nuclei to electromagnetic and weak probes, but they are computationally intensive and only applicable to the inclusive response. In the present work we introduce a novel approach, based on realistic models of nuclear interactions and currents, to evaluate the short-time (high-energy) inclusive and exclusive response of nuclei. The approach accounts reliably for crucial two-nucleon dynamics, including correlations and currents, and provides information on back-to-back nucleons observed in electron and neutrino scattering experiments. We demonstrate that in the quasielastic regime and at moderate momentum transfers both initial- and final-state correlations and two-nucleon currents are important for a quantitatively successful description of the inclusive response and final-state nucleons. Finally, the approach can be extended to include relativistic-kinematical and dynamical-effects, at least approximately in the two-nucleon sector, and to describe the response in the resonance-excitation region.

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Intrinsic Transverse Momentum And Evolution In Weighted Spin Asymmetries, Jian-Wei Qiu, Ted C. Rogers, Bowen Wang Jan 2020

Intrinsic Transverse Momentum And Evolution In Weighted Spin Asymmetries, Jian-Wei Qiu, Ted C. Rogers, Bowen Wang

Physics Faculty Publications

The transverse momentum-dependent (TMD) and collinear higher twist theoretical factorization frameworks are the most frequently used approaches to describe spin-dependent hard cross sections weighted by and integrated over transverse momentum. Of particular interest is the contribution from small transverse momentum associated with the target bound state. In phenomenological applications, this contribution is often investigated using transverse momentum weighted integrals that sharply regulate the large transverse momentum contribution, for example, with Gaussian parametrizations. Since the result is a kind of hybrid of TMD and collinear (inclusive) treatments, it is important to establish if and how the formalisms are related in applications …

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Observation Of In-Plane Magnetic Field Induced Phase Transitions In Fese, Jong Mok Ok, Chang Il Kwon, Yoshimitsu Kohama, Jung Sang You, Sun Kyu Park, Ji-Hye Kim, Y.J. Jo, E.S. Choi, Koichi Kindo, Woun Kang, Ki-Seok Kim, E. G. Moon, Alex Gurevich, Jun Sung Kim Jan 2020

Observation Of In-Plane Magnetic Field Induced Phase Transitions In Fese, Jong Mok Ok, Chang Il Kwon, Yoshimitsu Kohama, Jung Sang You, Sun Kyu Park, Ji-Hye Kim, Y.J. Jo, E.S. Choi, Koichi Kindo, Woun Kang, Ki-Seok Kim, E. G. Moon, Alex Gurevich, Jun Sung Kim

Physics Faculty Publications

We investigate thermodynamic properties of FeSe under in-plane magnetic fields using torque magnetometry, specific heat, and magnetocaloric measurements. Below the upper critical field Hc2, we observed the field induced anomalies at H1 ∼ 15 T and H2 ∼ 22 T near H ∥ ab and below a characteristic temperature T* ∼ 2 K. The transition magnetic fields H1 and H2 exhibit negligible dependence on both temperature and field orientation. This contrasts to the strong temperature and angle dependence of Hc2, suggesting that these anomalies are attributed to the field induced phase transitions, …

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B-Meson Light-Cone Distribution Amplitude From Euclidean Quantities, Wei Wang, Yu-Ming Wang, Ji Xu, Shuai Zhao Jan 2020

B-Meson Light-Cone Distribution Amplitude From Euclidean Quantities, Wei Wang, Yu-Ming Wang, Ji Xu, Shuai Zhao

Physics Faculty Publications

A new method for the model-independent determination of the light-cone distribution amplitude of the B-meson in heavy quark effective theory (HQET) is proposed by combining the large momentum effective theory and the numerical simulation technique on the Euclidean lattice. We demonstrate the autonomous scale dependence of the nonlocal quasi-HQET operator with the aid of the auxiliary field approach, and further determine the perturbative matching coefficient entering the hard-collinear factorization formula for the B-meson quasidistribution amplitude at the one-loop accuracy. These results will be crucial to explore the partonic structure of heavy-quark hadrons in the static limit and to …

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Gluon Pseudo-Distributions At Short Distances: Forward Case, Ian Balitsky, Wayne Morris, Anatoly Radyushkin Jan 2020

Gluon Pseudo-Distributions At Short Distances: Forward Case, Ian Balitsky, Wayne Morris, Anatoly Radyushkin

Physics Faculty Publications

We present the results that are necessary in the ongoing lattice calculations of the gluon parton distribution functions (PDFs) within the pseudo-PDF approach. We give a classification of possible two-gluon correlator functions and identify those that contain the invariant amplitude determining the gluon PDF in the light-cone z2 → 0 limit. One-loop calculations have been performed in the coordinate representation and in an explicitly gauge-invariant form. We made an effort to separate ultraviolet (UV) and infrared (IR) sources of the ln⁡(−z2)-dependence at short distances z2. The UV terms cancel in the reduced Ioffe-time distribution (ITD), …

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Klf Analysis Report: Meson Spectroscopy Simulation Studies, Shankar Adhikari, Moskov Amaryan Jan 2020

Klf Analysis Report: Meson Spectroscopy Simulation Studies, Shankar Adhikari, Moskov Amaryan

Physics Faculty Publications

This analysis report is written as a supplemental for the strange meson spectroscopy part of the KLF proposal submitted to the JLab PAC48.

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