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Full-Text Articles in Physics

Detailed Study Of Quark-Hadron Duality In Spin Structure Functions Of The Proton And Neutron, V. Lagerquist, S. E. Kuhn, N. Sato Jan 2023

Detailed Study Of Quark-Hadron Duality In Spin Structure Functions Of The Proton And Neutron, V. Lagerquist, S. E. Kuhn, N. Sato

Physics Faculty Publications

Background: The response of hadrons, the bound states of the strong force (QCD), to external probes can be described in two different, complementary frameworks: as direct interactions with their fundamental constituents, quarks and gluons, or alternatively as elastic or inelastic coherent scattering that leaves the hadrons in their ground state or in one of their excited (resonance) states. The former picture emerges most clearly in hard processes with high momentum transfer, where the hadron response can be described by the perturbative expansion of QCD, while at lower energy and momentum transfers, the resonant excitations of the hadrons dominate the cross …


Multidimensional, High Precision Measurements Of Beam Single Spin Asymmetries In Semi-Inclusive 𝜋⁺ Electroproduction Off Protons In The Valence Region, S. Diehl, A. Kim, G. Angelini, K. Joo, S. Adhikari, M. J. Amaryan, M. Arratia, H. Atac, H. Avakian, C. Ayerbe Gayoso, N. A. Baltzell, L. Barion, S. Bastami, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, Et Al. Jan 2022

Multidimensional, High Precision Measurements Of Beam Single Spin Asymmetries In Semi-Inclusive 𝜋⁺ Electroproduction Off Protons In The Valence Region, S. Diehl, A. Kim, G. Angelini, K. Joo, S. Adhikari, M. J. Amaryan, M. Arratia, H. Atac, H. Avakian, C. Ayerbe Gayoso, N. A. Baltzell, L. Barion, S. Bastami, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, Et Al.

Physics Faculty Publications

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π+ SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q2 ranging from 1–7  GeV2. In particular, the structure function ratio FsinϕLU/FUU has been determined, where FsinϕLU is a twist-3 …


Combining Nonperturbative Transverse Momentum Dependence With Tmd Evolution, J.O. Gonzalez-Hernandez, T. C. Rogers, N. Sato Jan 2022

Combining Nonperturbative Transverse Momentum Dependence With Tmd Evolution, J.O. Gonzalez-Hernandez, T. C. Rogers, N. Sato

Physics Faculty Publications

Central to understanding the nonperturbative, intrinsic partonic nature of hadron structure are the concepts of transverse momentum dependent (TMD) parton distribution and fragmentation functions. A TMD factorization approach to the phenomenology of semi-inclusive processes that includes evolution, higher orders, and matching to larger transverse momentum is ultimately necessary for reliably connecting with phenomenologically extracted nonperturbative structures, especially when widely different scales are involved. In this paper, we will address some of the difficulties that arise when phenomenological techniques that were originally designed for very high energy applications are extended to studies of hadron structures, and we will solidify the connection …


Weak Values From Strong Interactions In Neutron Interferometry, Tobias Denkmayr, Justin Dressel, Hermann Geppert-Kleinrath, Yuji Hasegawa, Stephan Sponar Apr 2018

Weak Values From Strong Interactions In Neutron Interferometry, Tobias Denkmayr, Justin Dressel, Hermann Geppert-Kleinrath, Yuji Hasegawa, Stephan Sponar

Mathematics, Physics, and Computer Science Faculty Articles and Research

In their original framework weak values must be measured by weak measurements that are minimally disturbing, meaning that the coupling between an investigated quantum system and a measurement device has no influence on the evolution of the system. However, under certain circumstances this weakness of the interaction is not necessary. In that case weak values can still be exactly determined from the statistics of the outcomes of arbitrary-strength generalized measurements. Here, we report an experimental procedure for neutron matter-waves that extends the notion of generalized eigenvalues for the neutron’s path system to allow the exact determination of weak values using …


Weak Values Obtained In Matter-Wave Interferometry, Stephan Sponar, Tobias Denkmayr, Hermann Geppert, Hartmutt Lemmel, Alexandre Matzkin, Jeff Tollaksen, Yuji Hasegawa Jan 2015

Weak Values Obtained In Matter-Wave Interferometry, Stephan Sponar, Tobias Denkmayr, Hermann Geppert, Hartmutt Lemmel, Alexandre Matzkin, Jeff Tollaksen, Yuji Hasegawa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Weak values, introduced more than 25 years ago, underwent a metamorphosis from a theoretical curiosity to a powerful resource in photonics for exploring foundations of quantum mechanics, as well as a practical laboratory tool. Due to the tiny coherence volume of particles used in matter-wave optics, a straightforward implementation of weak measurements is not feasible. We have overcome this hurdle by developing a method to weakly measure a massive particle's spin component. A neutron optical approach is realized by utilizing neutron interferometry, where the neutron's spin is coupled weakly to its spatial degree of freedom. Here, we present how one …


Quantum Cheshire Cats, Yakir Aharonov, Sandu Popescu, Daniel Rohrlich, Paul Skrzypczyk Jan 2013

Quantum Cheshire Cats, Yakir Aharonov, Sandu Popescu, Daniel Rohrlich, Paul Skrzypczyk

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper we present a quantum Cheshire Cat. In a pre- and post-selected experiment we find the Cat in one place, and its grin in another. The Cat is a photon, while the grin is its circular polarization.


Stern-Gerlach Dynamics With Quantum Propagators, Bailey C. Hsu, Manuel Berrondo, Jean F. Van Huele Jan 2011

Stern-Gerlach Dynamics With Quantum Propagators, Bailey C. Hsu, Manuel Berrondo, Jean F. Van Huele

Faculty Publications

We study the quantum dynamics of a nonrelativistic neutral particle with spin in inhomogeneous external magnetic fields. We first consider fields with one-dimensional inhomogeneities, both unphysical and physical, and construct the corresponding analytic propagators. We then consider fields with two-dimensional inhomogeneities and develop an appropriate numerical propagation method. We propagate initial states exhibiting different degrees of space localization and various initial spin configurations, including both pure and mixed spin states. We study the evolution of their spin densities and identify characteristic features of spin density dynamics, such as the spatial separation of spin components, and spin localization or accumulation. We …


Quantum Interference Experiments, Modular Variables And Weak Measurements, Jeff Tollaksen, Yakir Aharonov, Aharon Casher, Tirzah Kaufherr, Shmuel Nussinov Jan 2010

Quantum Interference Experiments, Modular Variables And Weak Measurements, Jeff Tollaksen, Yakir Aharonov, Aharon Casher, Tirzah Kaufherr, Shmuel Nussinov

Mathematics, Physics, and Computer Science Faculty Articles and Research

We address the problem of interference using the Heisenberg picture and highlight some new aspects through the use of pre-selection, post-selection, weak measurements and modular variables. We present a physical explanation for the different behaviors of a single particle when the distant slit is open or closed; instead of having a quantum wave that passes through all slits, we have a localized particle with non-local interactions with the other slit(s). We introduce a Gedanken experiment to measure this non-local exchange. While the Heisenberg and Schrodinger pictures are equivalent formulations of quantum mechanics, nevertheless, the results discussed here support a new …


A Time-Symmetric Formulation Of Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Jeff Tollaksen Jan 2010

A Time-Symmetric Formulation Of Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Jeff Tollaksen

Mathematics, Physics, and Computer Science Faculty Articles and Research

Quantum mechanics allows one to independently select both the initial and final states of a single system. Such pre- and postselection reveals novel effects that challenge our ideas about what time is and how it flows.


Search For The Photoexcitation Of Exotic Mesons In The Π+Π+Π- System, Clas Collaboration, M. J. Amaryan, H. Bagdasaryan, S. Bektasoglu, S. Bültmann, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, L. M. Qin, S. Tkachenko, L. B. Weinstein, J. Zhang Jan 2009

Search For The Photoexcitation Of Exotic Mesons In The Π+Π+Π- System, Clas Collaboration, M. J. Amaryan, H. Bagdasaryan, S. Bektasoglu, S. Bültmann, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, L. M. Qin, S. Tkachenko, L. B. Weinstein, J. Zhang

Physics Faculty Publications

A search for exotic mesons in the π+π+π system photoproduced by the charge exchange reaction γp→π+π+π(n) was carried out by the CLAS Collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A partial wave analysis was performed on a sample of 83 000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the …


Long-Time Electron Spin Storage Via Dynamical Suppression Of Hyperfine-Induced Decoherence In A Quantum Dot, Wenxian Zhang, N. P. Konstantinidis, V. V. Dobrovitski, B. N. Harmon, Lea F. Santos, Lorenza Viola Mar 2008

Long-Time Electron Spin Storage Via Dynamical Suppression Of Hyperfine-Induced Decoherence In A Quantum Dot, Wenxian Zhang, N. P. Konstantinidis, V. V. Dobrovitski, B. N. Harmon, Lea F. Santos, Lorenza Viola

Dartmouth Scholarship

The coherence time of an electron spin decohered by the nuclear spin environment in a quantum dot can be substantially increased by subjecting the electron to suitable dynamical decoupling sequences. We analyze the performance of high-level decoupling protocols by using a combination of analytical and exact numerical methods, and by paying special attention to the regimes of large interpulse delays and long-time dynamics, which are outside the reach of standard average Hamiltonian theory descriptions. We demonstrate that dynamical decoupling can remain efficient far beyond its formal domain of applicability, and find that a protocol exploiting concatenated design provides best performance …


Measurement Of Deeply Virtual Compton Scattering Beam-Spin Asymmetries, Clas Collaboration, H. Bagdasaryan, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, C. E. Hyde, H. G. Juengst, N. Kalantarians, A. Klein, A. V. Klimenko, S. E. Kuhn, J. Lachniet, S. Tkachenko, L. B. Weinstein, J. Zhang Jan 2008

Measurement Of Deeply Virtual Compton Scattering Beam-Spin Asymmetries, Clas Collaboration, H. Bagdasaryan, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, C. E. Hyde, H. G. Juengst, N. Kalantarians, A. Klein, A. V. Klimenko, S. E. Kuhn, J. Lachniet, S. Tkachenko, L. B. Weinstein, J. Zhang

Physics Faculty Publications

The beam-spin asymmetries in the hard exclusive electroproduction of photons on the proton (ep→epγ ) were measured over a wide kinematic range and with high statistical accuracy. These asymmetries result from the interference of the Bethe-Heitler process and of deeply virtual Compton scattering. Over the whole kinematic range (xB from 0.11 to 0.58, Q2 from 1 to 4.8  GeV2, −t from 0.09 to 1.8  GeV2), the azimuthal dependence of the asymmetries is compatible with expectations from leading-twist dominance, A ≃ asinϕ/(1+ccosϕ). This extensive set of data can thus be used to …


Color Transparency In Qcd And Post-Selection In Quantum Mechanics, Shmuel Nussinov, Jeff Tollaksen Jan 2008

Color Transparency In Qcd And Post-Selection In Quantum Mechanics, Shmuel Nussinov, Jeff Tollaksen

Mathematics, Physics, and Computer Science Faculty Articles and Research

We discuss color transparency in the nuclear QCD context from the perspective of pre- and post-selected ensembles. We show that the small size of the hadronic states can be explained by the peculiar "force of post-selection," in contrast to the more standard explanation based on external forces.


First Measurement Of Beam-Recoil Observables CX And CZ In Hyperon Photoproduction, M. J. Amaryan, H. Bagdasaryan, H. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration Jan 2007

First Measurement Of Beam-Recoil Observables CX And CZ In Hyperon Photoproduction, M. J. Amaryan, H. Bagdasaryan, H. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, S. E. Kuhn, J. Lachniet, M. R. Niroula, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration

Physics Faculty Publications

Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions γ + p → K+ + Λ and γ+p → K+ + Σ0. The data were obtained using the CEBAF Large Acceptance Spectrometer (CLAS) detector at the Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 < cos θc.m.K+ < +0.95. For the Λ, the polarization transfer coefficient along the photon momentum axis, Cz, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient Cx is smaller than Cz by a roughly …


Η’ Photoproduction On The Proton For Photon Energies From 1.527 To 2.227 Gev, M. Bektasoglu, S.L. Careccia, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, H. G. Juengst, A. Klein, S. E. Kuhn, A. V. Klimenko, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang, Et Al., Clas Collaboration Jan 2006

Η’ Photoproduction On The Proton For Photon Energies From 1.527 To 2.227 Gev, M. Bektasoglu, S.L. Careccia, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, H. G. Juengst, A. Klein, S. E. Kuhn, A. V. Klimenko, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang, Et Al., Clas Collaboration

Physics Faculty Publications

Differential cross sections for the reaction γp→η′p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data suggest for the first time the coupling of the η′N channel to both the S11(1535) and P11(1710) resonances, known to couple strongly to the ηN channel in photoproduction on the proton, and the importance of J=3/2 resonances in the process.