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Articles 31 - 60 of 838
Full-Text Articles in Physics
Two-Point Correlator Of Twist-2 Light-Ray Operators In N=Sym In Bfkl Approximation, Ian Balitsky, Vladimir Kazakov, Evgeny Sobko
Two-Point Correlator Of Twist-2 Light-Ray Operators In N=Sym In Bfkl Approximation, Ian Balitsky, Vladimir Kazakov, Evgeny Sobko
Physics Faculty Publications
We generalize local operators of the leading twist-2 of š© = SYM theory to the case of complex Lorentz spin j using principal series representation of sl(2, R). We give the direct computation of correlation function of two such non-local operators in the BFKL regime when j ā 1. The correlator appears to have the expected conformal coordinate dependence governed by the anomalous dimension of twist-2 operator in NLO BFKL approximation predicted by Kotikov and Lipatov.
First Measurement Of Hard Exclusive šā»Īāŗāŗ Electroproduction Beam-Spin Asymmetries Off The Proton, S. Diehl, N. Trotta, K. Joo, P. Achenbach, Z. Akbar, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, F. BossĆ¹, K.-T. Brinkman, M. Zurek, Et Al., Clas Collaboration
First Measurement Of Hard Exclusive šā»Īāŗāŗ Electroproduction Beam-Spin Asymmetries Off The Proton, S. Diehl, N. Trotta, K. Joo, P. Achenbach, Z. Akbar, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, F. BossĆ¹, K.-T. Brinkman, M. Zurek, Et Al., Clas Collaboration
Physics Faculty Publications
The polarized cross-section ratio ĻLTā²/Ļ0 from hard exclusive ĻāĪ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2āāGeV/10.6āāGeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5āāGeV2 up to 7āāGeV2. The reaction provides a novel access to the d-quark content of the nucleon and to pāĪ++ transition generalized parton ā¦
Searching For Prompt And Long-Lived Dark Photons In Electroproduced Eāŗ Eā» Pairs With The Heavy Photon Search Experiment At Jlab, P. H. Adrian, N. A. Baltzell, M. Battaglieri, M. BondĆ, S. Boyarinov, S. Bueltmann, P. Butti, V. D. Burkert, D. Calvo, T. Cao, M. Carpinelli, A. Celentano, G. Charles, L. Colaneri, W. Cooper, D. Crowe, C. Cuevas, A. D'Angelo, N. Dashyan, B. Wojtsekhowski, Et Al.
Searching For Prompt And Long-Lived Dark Photons In Electroproduced Eāŗ Eā» Pairs With The Heavy Photon Search Experiment At Jlab, P. H. Adrian, N. A. Baltzell, M. Battaglieri, M. BondĆ, S. Boyarinov, S. Bueltmann, P. Butti, V. D. Burkert, D. Calvo, T. Cao, M. Carpinelli, A. Celentano, G. Charles, L. Colaneri, W. Cooper, D. Crowe, C. Cuevas, A. D'Angelo, N. Dashyan, B. Wojtsekhowski, Et Al.
Physics Faculty Publications
The heavy photon search experiment (HPS) at the Thomas Jefferson National Accelerator Facility searches for electroproduced dark photons. We report results from the 2016 engineering run consisting of 10ā608āānbā1 of data for both the prompt and displaced vertex searches. A search for a prompt resonance in the e+eā invariant mass distribution between 39 and 179 MeV showed no evidence of dark photons above the large QED background, limiting the coupling of Īµ2ā³10ā5, in agreement with previous searches. The search for displaced vertices showed no evidence of excess signal over background ā¦
Superheating Field In Superconductors With Nanostructured Surfaces, W. P. M. R. Pathirana, A. Gurevich
Superheating Field In Superconductors With Nanostructured Surfaces, W. P. M. R. Pathirana, A. Gurevich
Physics Faculty Publications
We report calculations of a dc superheating field Hsh in superconductors with nanostructured surfaces. Numerical simulations of the Ginzburg-Landau (GL) equations were performed for a superconductor with an inhomogeneous impurity concentration, a thin superconducting layer on top of another superconductor, and superconductor-insulator-superconductor (S-I-S) multilayers.The superheating field was calculated taking into account the instability of the Meissner state with a nonzero wavelength along the surface, which is essential for realistic values of the GL parameter Īŗ. Simulations were done for the materials parameters of Nb and Nb3Sn at different values of Īŗ and the mean free paths. We ā¦
Magnetic Field Mapping Of A Large-Grain 1.3 Ghz Single-Cell Cavity, Ishwari Prasad Parajuli, Jean R. Delayen, Alex V. Gurevich, Gianluigi Ciovati
Magnetic Field Mapping Of A Large-Grain 1.3 Ghz Single-Cell Cavity, Ishwari Prasad Parajuli, Jean R. Delayen, Alex V. Gurevich, Gianluigi Ciovati
Physics Faculty Publications
A new magnetic field mapping system for 1.3 GHz single-cell cavities was developed in order to reveal the impact of ambient magnetic field and temperature gradients during cool-down on the flux trapping phenomenon. Measurements were done at 2 K for different cool-down conditions of a large-grain cavity before and after 120 Ā°C bake. The fraction of applied magnetic field trapped in the cavity walls was ~ 50% after slow cool-down and ~ 20% after fast cool-down. The results showed a weak correlation between between trapped flux locations and hot-spots causing the high-field Q-slope. The results also showed an increase of ā¦
Development And Performance Of Rfd Crab Cavity Prototypes For Hl-Lhc Aup, L. Listori, P. Berrutti, M. Narduzzi, A. Castilla, S. U. De Silva, J. R. Delayen, N. A. Huque, Z. Li, A. Ratti
Development And Performance Of Rfd Crab Cavity Prototypes For Hl-Lhc Aup, L. Listori, P. Berrutti, M. Narduzzi, A. Castilla, S. U. De Silva, J. R. Delayen, N. A. Huque, Z. Li, A. Ratti
Physics Faculty Publications
The US will be contributing to the HL-LHC upgrade at CERN with the fabrication and qualification of RFD crabbing cavities in the framework of the HL-LHC Accelerator Upgrade Project (AUP) managed by Fermilab. AUP received Critical Decision 3 (CD-3) approval by DOE in December 2020 launching the project into the production phase. The electro-magnetic design of the cavity was inherited from the LHC Accelerator Research Program (LARP) but needed to be revised to meet new project requirements and to prevent issues encountered during beam tests performed at CERN in the R&D phase. Two prototype cavities were manufactured in industry and ā¦
Full Treatment Of The Thrust Distribution In Single Inclusive EāŗEā» ā H X Processes, M. Boglione, Andrea Simonelli
Full Treatment Of The Thrust Distribution In Single Inclusive EāŗEā» ā H X Processes, M. Boglione, Andrea Simonelli
Physics Faculty Publications
Extending the transverse momentum dependent factorization to thrust dependent observables entails a series of difficulties, ultimately associated to the behavior of soft radiation. As a consequence, the definition of the transverse momentum dependent functions has to be revised, while preserving (and possibly extending) their universality properties. Moreover, the regularization of the rapidity divergences generates non trivial correlations between rapidity and thrust. In this paper, we show how to deal with these correlations in a consistent treatment of the thrust dependence of e+eā ā h X cross section, where the hadron transverse momentum is measured with respect to ā¦
Eic 197 Mhz Crab Cavity Rf Optimization, Zenghai Li, Subashini U. De Silva, Jean R. Delayen, Robert A. Rimmer, Qiong Wu, Binping Xiao, Wencan Xu
Eic 197 Mhz Crab Cavity Rf Optimization, Zenghai Li, Subashini U. De Silva, Jean R. Delayen, Robert A. Rimmer, Qiong Wu, Binping Xiao, Wencan Xu
Physics Faculty Publications
Crab cavities, operating at 197 MHz and 394 MHz respectively, will be used to compensate the loss of luminosity due to a 25 mrad crossing angle at the interaction point in the Electron Ion Collider (EIC). Both crab cavities are of the RF Dipole (RFD) shape. To meet the machine design requirements, there are a few important cavity design considerations that need to be addressed. First, to achieve stable cavity operation at the design voltages, cavity geometry details must be optimized to suppress potential multipacting. Incorporating strong HOM damping in the cavity design is required for the beam stability and ā¦
First Measurement Of The Emc Effect In Ā¹ā°B And Ā¹Ā¹B, A. Karki, D. Biswas, F. A. Gonzalez, W. Henry, C. Morean, A. Nadeeshani, A. Sun, D. Abrams, Z. Ahmed, B. Aljawrneh, S. Alsalmi, R. Ambrose, D. Androic, W. Armstrong, J. Arrington, D. Asaturyan, K. Assumin-Gyimah, C. Ayerbe Gayoso, A. Bandari, J. Zhang, Et Al., Hall C. Collaboration
First Measurement Of The Emc Effect In Ā¹ā°B And Ā¹Ā¹B, A. Karki, D. Biswas, F. A. Gonzalez, W. Henry, C. Morean, A. Nadeeshani, A. Sun, D. Abrams, Z. Ahmed, B. Aljawrneh, S. Alsalmi, R. Ambrose, D. Androic, W. Armstrong, J. Arrington, D. Asaturyan, K. Assumin-Gyimah, C. Ayerbe Gayoso, A. Bandari, J. Zhang, Et Al., Hall C. Collaboration
Physics Faculty Publications
The nuclear dependence of the inclusive inelastic electron scattering cross section (the EMC effect) has been measured for the first time in 10B and 11B. Previous measurements of the EMC effect in A ā¤ 12 nuclei showed an unexpected nuclear dependence; 10B and 11B were measured to explore the EMC effect in this region in more detail. Results are presented for 9Be, 10B, 11B, and 12C at an incident beam energy of 10.6 GeV. The EMC effect in the boron isotopes was found to be similar to ā¦
First Use Of A Longitudinally Polarized Target With Clas12, C. D. Keith, J. Brock, C. Carlin, T. Kageya, V. Lagerquist, J. Maxwell, P. Pandey
First Use Of A Longitudinally Polarized Target With Clas12, C. D. Keith, J. Brock, C. Carlin, T. Kageya, V. Lagerquist, J. Maxwell, P. Pandey
Physics Faculty Publications
Run Group C comprises eight experiments utilizing the CLAS12 detector system in Hall B at Jefferson Lab to study the multidimensional partonic structure of nucleons. The experiments scatter electrons from polarized protons and neutrons in samples of solid NH3 and ND3, dynamically polarized at a temperature of 1 K in a 5 T magnetic field. After a brief description of the target system, the current status of the target and preliminary results of its performance in the experiment are presented.
Electron Scattering And Neutrino Physics, A. M. Ankowski, A. Ashkenazi, S. Bacca, J. L. Barrow, M. Betancourt, A. Bodek, M. E. Christy, L. Doria, S. Dytman, A. Friedland, O. Hen, C. J. Horowitz, N. Jachowicz, W. Ketchum, T. Lux, K. Mahn, C. Mariani, J. Newby, V. Pandey, A. Papadopoulou, E. Radicioni, F. SĆ”nchez, C. Sfienti, J. M. UdĆas, L. Weinstein, L. Alvarez-Ruso, J. E. Amaro, C. A. ArgĆ¼elles, A. B. Balantekin, S. Bolognesi, V. Brdar, P. Butti, S. Carey, Z. Djurcic, O. Dvornikov, S. Edayath, S. Gardiner, J. Isaacson, W. Jay, K. S. Mcfarland, A. Nikolakopoulos, A. Norrick, S. Pastore, G. Paz, M. H. Reno, I. Ruiz Simo, J. E. Sobczyk, A. Sousa, N. Toro, Y. D. Tsai, M. Wagman, J. G. Walsh, G. Yang
Electron Scattering And Neutrino Physics, A. M. Ankowski, A. Ashkenazi, S. Bacca, J. L. Barrow, M. Betancourt, A. Bodek, M. E. Christy, L. Doria, S. Dytman, A. Friedland, O. Hen, C. J. Horowitz, N. Jachowicz, W. Ketchum, T. Lux, K. Mahn, C. Mariani, J. Newby, V. Pandey, A. Papadopoulou, E. Radicioni, F. SĆ”nchez, C. Sfienti, J. M. UdĆas, L. Weinstein, L. Alvarez-Ruso, J. E. Amaro, C. A. ArgĆ¼elles, A. B. Balantekin, S. Bolognesi, V. Brdar, P. Butti, S. Carey, Z. Djurcic, O. Dvornikov, S. Edayath, S. Gardiner, J. Isaacson, W. Jay, K. S. Mcfarland, A. Nikolakopoulos, A. Norrick, S. Pastore, G. Paz, M. H. Reno, I. Ruiz Simo, J. E. Sobczyk, A. Sousa, N. Toro, Y. D. Tsai, M. Wagman, J. G. Walsh, G. Yang
Physics Faculty Publications
A thorough understanding of neutrinoānucleus scattering physics is crucial for the successful execution of the entire US neutrino physics program. Neutrinoānucleus interaction constitutes one of the biggest systematic uncertainties in neutrino experimentsāboth at intermediate energies affecting long-baseline deep underground neutrino experiment, as well as at low energies affecting coherent scattering neutrino programāand could well be the difference between achieving or missing discovery level precision. To this end, electronānucleus scattering experiments provide vital information to test, assess and validate different nuclear models and event generators intended to test, assess and validate different nuclear models and event generators intended to be used ā¦
Nuclear Magnetic Quadrupole Moment Of Ā¹ā·āµLu And Parity-Violating Polarization Degree Of Levels In Ā¹ā·āµLuohāŗ, Igor Kurchavov, Daniel Maison, Leonid Skripnikov, Matt Grau, Alexander Petrov
Nuclear Magnetic Quadrupole Moment Of Ā¹ā·āµLu And Parity-Violating Polarization Degree Of Levels In Ā¹ā·āµLuohāŗ, Igor Kurchavov, Daniel Maison, Leonid Skripnikov, Matt Grau, Alexander Petrov
Physics Faculty Publications
A calculation is performed of the parity-violating polarizations in the external electric field, which are associated with the electron electric dipole moment (eEDM) and magnetic quadrupole moment (MQM) of the 175Lu nucleus, as well as the determination of the rovibrational structure for the 175LuOH+ cation. Beyond the bending of the molecule, the slight effect of the stretching of the distance between Lu and OH is taken into account. This study is required for the preparation of the experiment and for the extraction of the eEDM and MQM values of 175Lu from future measurements.
Superconducting Non-Elliptical Cavities (Tem Cavity Designs), Subashini De Silva
Superconducting Non-Elliptical Cavities (Tem Cavity Designs), Subashini De Silva
Physics Faculty Publications
This lecture will present fundamental of RF to accelerate or reflect beams. The lecture will cover the electrical design method of the SRF high/medium/low beta cavities. The difference in the cavity design between TM mode and TE will be emphasized.
Understanding The Field And Frequency Dependence Of Rf Loss In Srf Cavities, Pashupati Dhakal, G. Ciovati, Alex V. Gurevich, Bashu D. Khanal
Understanding The Field And Frequency Dependence Of Rf Loss In Srf Cavities, Pashupati Dhakal, G. Ciovati, Alex V. Gurevich, Bashu D. Khanal
Physics Faculty Publications
SRF cavities subjected to heat treatment below 200 Ā°C in the presence of nitrogen showed an improvement in quality factor while maintaining an accelerating gradient above 25 MV/m. Here, we report the rf performance of several single-cell superconducting radio frequency cavities with frequency ranging from 0.75 - 3.0 GHz subjected to low temperature heat treatment in nitrogen environment. The cavities were treated at temperature 120 - 175 oC for 24 - 48 hours in low partial pressure of ultra-pure nitrogen gas. The improvement in Qā with Q-rise was observed when nitrogen gas was injected ~300 Ā°C during the furnace treatment. ā¦
Basics Of Factorization In A Scalar Yukawa Field Theory, F. Aslan, L. Gamberg, J.O. Gonzalez-Hernandez, T. Rainaldi, T. C. Rogers
Basics Of Factorization In A Scalar Yukawa Field Theory, F. Aslan, L. Gamberg, J.O. Gonzalez-Hernandez, T. Rainaldi, T. C. Rogers
Physics Faculty Publications
The factorization theorems of QCD apply equally well to most simple quantum field theories that require renormalization but where direct calculations are much more straightforward. Working with these simpler theories is convenient for stress testing the limits of the factorization program and for examining general properties of the parton density functions or other correlation functions that might be necessary for a factorized description of a process. With this view in mind, we review the steps of factorization in a real scalar Yukawa field theory for both deep inelastic scattering and semi-inclusive deep inelastic scattering cross sections. In the case of ā¦
Neutrino-Tagged Jets At The Electron Ion Collider, Miguel Arratia, Zhong-Bo Kang, Sebouh J. Paul, Alexei Prokudin, Felix Ringer, Fanyi Zhao
Neutrino-Tagged Jets At The Electron Ion Collider, Miguel Arratia, Zhong-Bo Kang, Sebouh J. Paul, Alexei Prokudin, Felix Ringer, Fanyi Zhao
Physics Faculty Publications
We explore the potential of jet observables in charged-current deep inelastic scattering events at the future Electron-Ion Collider. Tagging jets with a recoiling neutrino, which can be identified by the eventās missing transverse momentum, will allow for flavor-sensitive measurements of transverse momentum dependent parton distribution functions. We present the first predictions for transverse-spin asymmetries in azimuthal neutrino-jet correlations and hadron-in-jet measurements. We study the kinematic reach and the precision of these measurements and explore their feasibility using parametrized detector simulations. We conclude that jet production in charged-current deep inelastic scattering, while challenging in terms of luminosity requirements, will complement the ā¦
Resolution To The Problem Of Consistent Large Transverse Momentum In Tmds, J. O. Gonzalez-Hernandez, Tommaso Rainaldi, Ted Rogers
Resolution To The Problem Of Consistent Large Transverse Momentum In Tmds, J. O. Gonzalez-Hernandez, Tommaso Rainaldi, Ted Rogers
Physics Faculty Publications
Parametrizing TMD parton densities and fragmentation functions in ways that consistently match their large transverse-momentum behavior in standard collinear factorization has remained notoriously difficult. We show how the problem is solved in a recently introduced set of steps for combining perturbative and nonperturbative transverse momentum in TMD factorization. Called a ābottom-upā approach in a previous article, here we call it a āhadron structure orientedā (HSO) approach to emphasize its focus on preserving a connection to the TMD parton model interpretation. We show that the associated consistency constraints improve considerably the agreement between parametrizations of TMD functions and their large-kT behavior, ā¦
Observation Of Large Missing-Momentum (E, E' P) Cross-Section Scaling And The Onset Of Correlated-Pair Dominance In Nuclei, I. Korover, A. W. Denniston, A. Kiral, A. Schmidt, A. Lovato, N. Rocco, A. Nikolakopoulos, L. B. Weinstein, E. Piasetzky, O. Hen, M. J. Amaryan, Giovanni Angelini, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, Fatiha Benmokhtar, A. Bianconi, Z. W. Zhao, Et Al., Clas Collaboration
Observation Of Large Missing-Momentum (E, E' P) Cross-Section Scaling And The Onset Of Correlated-Pair Dominance In Nuclei, I. Korover, A. W. Denniston, A. Kiral, A. Schmidt, A. Lovato, N. Rocco, A. Nikolakopoulos, L. B. Weinstein, E. Piasetzky, O. Hen, M. J. Amaryan, Giovanni Angelini, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, Fatiha Benmokhtar, A. Bianconi, Z. W. Zhao, Et Al., Clas Collaboration
Physics Faculty Publications
We report the measurement of šB scaling in (e,eā²p) cross-section ratios off nuclei relative to deuterium at large missing momentum of 350 ā¤ Pmiss ā¤ 600 MeV/c. The observed scaling extends over a kinematic range of 0.7 ā¤ šB ā¤ 1.8, which is significantly wider than 1.4 ā¤ šB ā¤ 1.8 previously observed for inclusive (e,eā²) cross-section ratios. The šB-integrated cross-section ratios become constant (i.e., scale) beginning at pmiss ā kF, the nuclear Fermi momentum. Comparing with theoretical calculations we find good agreement with generalized contact formalism calculations for high missing ā¦
Crab Cavities For Ilc, P. A. Mcintosh, S. A. Belomestnykh, G. Burt, R. Calaga, S. U. De Silva, J. R. Delayen, I. V. Gonin, T. N. Khabiboulline, A. Lunin, T. Okugi, Y. M. Orlov, S. VerdĆŗ-AndrĆ©s, B. P. Xiao, V. P. Yakovlev, A. Yamamoto
Crab Cavities For Ilc, P. A. Mcintosh, S. A. Belomestnykh, G. Burt, R. Calaga, S. U. De Silva, J. R. Delayen, I. V. Gonin, T. N. Khabiboulline, A. Lunin, T. Okugi, Y. M. Orlov, S. VerdĆŗ-AndrĆ©s, B. P. Xiao, V. P. Yakovlev, A. Yamamoto
Physics Faculty Publications
For the 14 mrad crossing angle proposed, crab cavity systems are fundamentally anticipated for the viable operation of the International Linear Collider (ILC), in order to maximise its luminosity performance. Since 2021, a specialist development team have been defining optimum crab cavity technologies which can fulfil the operational requirements for ILC, both for its baseline centre-of-mass energy of 250 GeV, but also extending those requirements out to higher beam collision intensities. Five design teams have established crab cavity technology solutions, which have the capability to also operate up to 1 TeV centre-of-mass. This presentation showcases the key performance capabilities of ā¦
Numerical Calculations Of Superheating Field In Superconductors With Nanostructured Surfaces, M.R.P. Walive Pathiranage, A. Gurevich
Numerical Calculations Of Superheating Field In Superconductors With Nanostructured Surfaces, M.R.P. Walive Pathiranage, A. Gurevich
Physics Faculty Publications
We reĀport calĀcuĀlaĀtions of a dc suĀperĀheatĀing field Hs in suĀperĀconĀducĀtors with nanosĀtrucĀtured surĀfaces. ParĀticĀuĀlarly, we perĀformed nuĀmerĀiĀcal simĀuĀlaĀtions of the Ginzburg-LanĀdau (GL) equaĀtions for a suĀperĀconĀducĀtor with an inĀhoĀmoĀgeĀneous proĀfile of imĀpuĀrity conĀcenĀtraĀtion, a thin suĀperĀconĀductĀing layer on top of anĀother suĀperĀconĀducĀtor, and S-I-S mulĀtiĀlayĀers. The suĀperĀheatĀing field was calĀcuĀlated takĀing into acĀcount the inĀstaĀbilĀity of the MeissĀner state at a fiĀnite waveĀlength along the surĀface deĀpendĀing on the value of the GL paĀraĀmeĀter. SimĀuĀlaĀtions were done for the maĀteĀriĀals paĀraĀmeĀters of Nb and NbāSn at difĀferĀent valĀues of the GL paĀraĀmeĀter and the mean free paths. We show ā¦
Quantum Efficiency Enhancement In Simulated Nanostructured Negative Electron Affinity Gaas Photocathodes, Md Aziz Ar Rahman, Shukui Zhang, Hani E. Elsayed-Ali
Quantum Efficiency Enhancement In Simulated Nanostructured Negative Electron Affinity Gaas Photocathodes, Md Aziz Ar Rahman, Shukui Zhang, Hani E. Elsayed-Ali
Physics Faculty Publications
Nanostructured negative electron affinity GaAs photocathodes for a polarized electron source are studied using finite difference time domain optical simulation. The structures studied are nanosquare columns, truncated nanocones, and truncated nanopyramids. Mie-type resonances in the 700ā800ānm waveband, suitable for generation of polarized electrons, are identified. At resonance wavelengths, the nanostructures can absorb up to 99% of the incident light. For nanosquare columns and truncated nanocones, the maximum quantum efficiency (QE) at 780ānm obtained from simulation is 27%, whereas for simulated nanopyramids, the QE is ā¼21%. The high photocathode quantum efficiency is due to the shift of Mie resonance ā¦
Prospects For š¾*š¾* ā šš Via Lattice Qcd, RaĆŗl BriceƱo, Andrew W. Jackura, Arkaitz Rodas, Juan V. Guerrero
Prospects For š¾*š¾* ā šš Via Lattice Qcd, RaĆŗl BriceƱo, Andrew W. Jackura, Arkaitz Rodas, Juan V. Guerrero
Physics Faculty Publications
The š¾*š¾* ā šš scattering amplitude plays a key role in a wide range of phenomena, including understanding the inner structure of scalar resonances as well as constraining the hadronic contributions to the anomalous magnetic moment of the muon. In this work, we explain how the infinite-volume Minkowski amplitude can be constrained from finite-volume Euclidean correlation functions. The relationship between the finite-volume Euclidean correlation functions and the desired amplitude holds up to energies where 3š states can go on shell, and is exact up to exponentially small corrections that scale like šŖ(eāmšL), where L is the spatial extent ā¦
Observation Of Correlations Between Spin And Transverse Momenta In Back-To-Back Dihadron Production At Clas12, H. Avakian, T.B. Hayward, A. Kotzinian, W.R. Armstrong, H. Atac, C. Ayerbe Gayoso, L. Baashen, N.A. Balzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, S. Boiarinov, M. Zurek, Et Al.
Observation Of Correlations Between Spin And Transverse Momenta In Back-To-Back Dihadron Production At Clas12, H. Avakian, T.B. Hayward, A. Kotzinian, W.R. Armstrong, H. Atac, C. Ayerbe Gayoso, L. Baashen, N.A. Balzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. S. Biselli, M. Bondi, S. Boiarinov, M. Zurek, Et Al.
Physics Faculty Publications
We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinĪĻ modulations in epāe'pĻ+ X events, where ĪĻ is the difference ā¦
Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Åirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang
Determination Of The Titanium Spectral Function From (E, E'P) Data, L. Jiang, A.M. Ankowski, D. Abrams, L. Gu, B. Aljawrneh, S. Alsalmi, J. Bane, A. Batz, S. Barcus, M. Barroso, V. Bellini, O. Benhar, J. Bericic, D. Biswas, A. Camsonne, J. Castellanos, J. -P. Chen, M. E. Christy, K. Craycraft, R. Cruz-Torres, H. Dai, D. Day, A. Dirican, S. -C. Dusa, E. Fuchey, T. Gautam, C. Giusti, J. Gomez, C. Gu, T. J. Hague, J. -O. Hansen, F. Hauenstein, D. W. Higinbotham, C. Hyde, Z. Jerzyk, A. M. Johnson, C. Keppel, C. Lanham, S. Li, R. Lindgren, H. Liu, C. Mariani, R. E. Mcclellan, D. Meekins, R. Michaels, M. Mihovilovic, M. Murphy, D. Nguyen, M. Nycz, L. Ou, B. Pandey, V. Pandey, K. Park, G. Perera, A.J.R. Puckett, S.N. Santiesteban, S. Åirca, T. Su, L. Tang, Y. Tian, N. Ton, B. Wojsekhowski, S. Wood, Z. Ye, J. Zhang
Physics Faculty Publications
The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,eā²p) cross section in parallel kinematics using a natural titanium target. In this paper, we report the analysis of the dataset obtained in different kinematics for our solid natural titanium target. Data were obtained in a range of missing momentum and missing energy between 15 ā² pm ā² 250āāMeV/c and 12 ā² Em ā² 80āāMeV, respectively, and using an electron beam energy of 2.2 GeV. We measured the reduced cross section with ā¼7% accuracy as a function of both missing momentum and missing energy. ā¦
Modeling A Nb3Sn Cryounit In Gpt At Uitf, Sunil Pokharel, A. S. Hofler, Geoffrey A. Krafft
Modeling A Nb3Sn Cryounit In Gpt At Uitf, Sunil Pokharel, A. S. Hofler, Geoffrey A. Krafft
Physics Faculty Publications
Nb3Sn is a prospective material for future superconducting radio frequency (SRF) accelerator cavities. Compared to conventional niobium, the material can achieve higher quality factors, higher temperature operation, and potentially higher accelerating gradients (Eacc ā 96 MV/m). In this work, we performed modeling of the Upgraded Injector Test Facility (UITF) at Jefferson Lab utilizing newly constructed Nb3Sn cavities. We studied the effects of the buncher cavity and varied the gun voltage from 200-500 keV. We have calibrated and optimized the SRF cavity gradients and phases for the Nb3Sn five-cell cavities' energy gains with the ā¦
Scattered Spectra From Inverse Compton Sources Operating At High Laser Fields And High Electron Energies, Geoffrey A. Krafft, BalÅ”a TerziÄ, Erik Johnson, G. Wilson
Scattered Spectra From Inverse Compton Sources Operating At High Laser Fields And High Electron Energies, Geoffrey A. Krafft, BalÅ”a TerziÄ, Erik Johnson, G. Wilson
Physics Faculty Publications
As Compton x-ray and gamma-ray sources become more prevalent, to understand their performance in a precise way, it becomes important to be able to compute the distribution of scattered photons precisely. For example, codes have been developed at Old Dominion University which were used to understand the performance of the Dresden Compton Source in detail. An ideal model would (i) include the full Compton effect frequency relations between incident and scattered photons, (ii) allow the field strength to be large enough that nonlinear effects are captured, and (iii) allow the effects of electron beam emittance to be introduced and studied. ā¦
Cavity And Cryomodule Developments For Eic, R. A. Rimmer, E. Daly, J. Guo, J. Henry, J. Matalevich, H. Wang, S. Wang, D. Holmes, K. Smith, W. Xu, A. Zaltsman, B. Xiao, Subashini De Silva, Jean R. Delayen
Cavity And Cryomodule Developments For Eic, R. A. Rimmer, E. Daly, J. Guo, J. Henry, J. Matalevich, H. Wang, S. Wang, D. Holmes, K. Smith, W. Xu, A. Zaltsman, B. Xiao, Subashini De Silva, Jean R. Delayen
Physics Faculty Publications
The EIC is a major new project under construction at BNL in partnership with JLab. It relies upon a number of new SRF cavities at 197 MHz, 394 MHz, 591 MHz and 1773 MHz to pre-bunch, accelerate, cool and crab the stored beams. R&D is focusing on the 591 MHz elliptical cavity and 197 MHz crab cavity first as these are the most challenging. Preliminary designs of these cavities are presented along with an R&D status report. To avoid developing multiple different cryostats a modular approach is adopted using a high degree of commonality of parts and systems. This approach ā¦
First Clas12 Measurement Of Deeply Virtual Compton Scattering Beam-Spin Asymmetries In The Extended Valence Region, G. Christiaens, M. Defurne, D. Sokhan, P. Achenbach, Z. Akbar, M. J. Amaryan, H. Atac, H. Avakian, C. Ayerbe Gayoso, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Zurek, Et Al., Clas Collaboration
First Clas12 Measurement Of Deeply Virtual Compton Scattering Beam-Spin Asymmetries In The Extended Valence Region, G. Christiaens, M. Defurne, D. Sokhan, P. Achenbach, Z. Akbar, M. J. Amaryan, H. Atac, H. Avakian, C. Ayerbe Gayoso, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Zurek, Et Al., Clas Collaboration
Physics Faculty Publications
Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q2 and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.
Surface Properties And Rf Performance Of Vapor Diffused NbāSn On Nb After Sequential Anneals Below 1000 Ā°C, Jayendrika K. Tiskumara, Jean R. Delayen, U. Pudasaini, G. Eremeev
Surface Properties And Rf Performance Of Vapor Diffused NbāSn On Nb After Sequential Anneals Below 1000 Ā°C, Jayendrika K. Tiskumara, Jean R. Delayen, U. Pudasaini, G. Eremeev
Physics Faculty Publications
NbāSn is a next-generation superconducting material that can be used for future superconducting radiofrequency (SRF) accelerator cavities, promising better performance, cost reduction, and higher operating temperature than Nb. The Sn vapor diffusion method is currently the most preferred and successful technique to coat niobium cavities with NbāSn. Among post-coating treatments to optimize the coating quality, higher temperature annealing without Sn is known to degrade NbāSn because of Sn loss. We have investigated NbāSn/Nb samples briefly annealed at 800-1000 Ā°C, for 10 and 20 minutes to potentially improve the surface to enhance the performance of NbāSn-coated cavities. Following the sample studies, ā¦
Temperature, Rf Field, And Frequency Dependence Performance Evaluation Of Superconducting Niobium Half-Wave Coaxial Cavity, N. K. Raut, G. Ciovati, S. U. De Silva, J. R. Delayen, P. Dhakal, B. D. Khanal, J. K. Tiskumara
Temperature, Rf Field, And Frequency Dependence Performance Evaluation Of Superconducting Niobium Half-Wave Coaxial Cavity, N. K. Raut, G. Ciovati, S. U. De Silva, J. R. Delayen, P. Dhakal, B. D. Khanal, J. K. Tiskumara
Physics Faculty Publications
Recent advancement in superconducting radio frequency cavity processing techniques, with diffusion of impurities within the RF penetration depth, resulted in high quality factor with increase in quality factor with increasing accelerating gradient. The increase in quality factor is the result of a decrease in the surface resistance as a result of nonmagnetic impurities doping and change in electronic density of states. The fundamental understanding of the dependence of surface resistance on frequency and surface preparation is still an active area of research. Here, we present the result of RF measurements of the TEM modes in a coaxial half-wave niobium cavity ā¦