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Huey-wen Lin - One of the best experts on this subject based on the ideXlab platform.
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Flavor Diagonal Tensor charges of the nucleon from (2+1+1)-flavor lattice QCD
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using eleven ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark (HISQ) action with 2+1+1 dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at $M_\pi=135$ MeV. Results for the proton in the $\overline{MS}$ scheme at 2~GeV are: $g_T^u = 0.784(28)(10)$, $g_T^d = -0.204(11)(10)$ and $g_T^s = -0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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flavor Diagonal Tensor charges of the nucleon from 2 1 1 flavor lattice qcd
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using 11 ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark action with $2+1+1$ dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at ${M}_{\ensuremath{\pi}}=135\text{ }\text{ }\mathrm{MeV}$. Results for the proton in the $\overline{\mathrm{MS}}$ scheme at 2 GeV are ${g}_{T}^{u}=0.784(28)(10)$, ${g}_{T}^{d}=\ensuremath{-}0.204(11)(10)$ and ${g}_{T}^{s}=\ensuremath{-}0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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Axial, Scalar and Tensor Charges of the Nucleon from 2+1+1-flavor Lattice QCD
Physical Review D, 2016Co-Authors: Tanmoy Bhattacharya, Rajan Gupta, Vincenzo Cirigliano, Huey-wen Lin, Saul D. Cohen, Boram YoonAbstract:We present results for the isovector axial, scalar and Tensor charges $g^{u-d}_A$, $g^{u-d}_S$ and $g^{u-d}_T$ of the nucleon needed to probe the Standard Model and novel physics. The axial charge is a fundamental parameter describing the weak interactions of nucleons. The scalar and Tensor charges probe novel interactions at the TeV scale in neutron and nuclear $\beta$-decays, and the flavor-Diagonal Tensor charges $g^{u}_T$, $g^{d}_T$ and $g^{s}_T$ are needed to quantify the contribution of the quark electric dipole moment (EDM) to the neutron EDM. The 9 ensembles, generated by the MILC Collaboration using the HISQ action with 2+1+1 dynamical flavors, span three lattice spacings $a \approx 0.06, 0.09$ and 0.12 fm and light-quark masses corresponding to the pion masses $M_\pi \approx 135, 225$ and 315 MeV. High-statistics estimates on five ensembles using the all-mode-averaging method allow us to quantify all systematic uncertainties and perform a simultaneous extrapolation in the lattice spacing, lattice volume and light-quark masses for the connected contributions. Our final estimates, in the $\overline{\text{MS}}$ scheme at 2 GeV, of the isovector charges are $g_A^{u-d} = 1.195(33)(20)$, $g_S^{u-d} = 0.97(12)(6) $ and $g_T^{u-d} = 0.987(51)(20)$. The first error includes statistical and all systematic uncertainties except that due to the extrapolation Ansatz, which is given by the second error estimate. Combining our estimate for $g_S^{u-d}$ with the difference of light quarks masses $(m_d-m_u)^{\rm QCD}=2.67(35)$ MeV given by FLAG, we obtain $(M_N-M_P)^{\rm QCD} = 2.59(49)$ MeV. Estimates of the connected part of the flavor-Diagonal Tensor charges of the proton are $g^{u}_T=0.792(42)$ and $g^{d}_T=-0.194(14)$. Combining our new estimates with precision low-energy experiments, we update constraints on novel scalar and Tensor interactions, $\epsilon_{S,T}$, at the TeV scale.
Qing Huo Liu - One of the best experts on this subject based on the ideXlab platform.
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The Diagonal Tensor Approximation (Dta) for Objects in a Non-Canonical Inhomogeneous Background
Progress In Electromagnetics Research, 2011Co-Authors: Mengqing Yuan, Qing Huo LiuAbstract:A non-canonical inhomogeneous background medium is one whose Green's function cannot be obtained by an analytical method. Electromagnetic scattering from objects embedded in a non-canonical inhomogeneous background medium is very challenging because of the computational complexity with the calculation of its Green's function and the multiple scattering between objects and the background. This work applies the Diagonal Tensor Approximation (DTA) to calculate the scattering from arbitrary objects in a non- canonical inhomogeneous background. Previously, the DTA has only been applied to a canonical background such as a homogeneous or layered background media. This approach employs a numerical method to obtain all Green's functions required in the calculation; an accurate DTA is used to calculate the scattering properties. In order to reduce the large number of simulations, we employ the symmetry and reciprocity in the Green's function calculation. Furthermore, considering that most realistic imaging measurements are made through a voltage probe usually represented by a wave port, we develop a method to convert the scattered fleld on the probe (the antenna) to the measured wave port voltage. Numerical results show that this method can obtain accurate scattering characteristics from arbitrary objects in a non-canonical inhomogeneous background medium in a microwave imaging system.
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Fast three-dimensional GPR forward and inverse scattering based on wideband Diagonal Tensor approximation
Digests of the 2010 14th Biennial IEEE Conference on Electromagnetic Field Computation, 2010Co-Authors: Yueqin Huang, Qing Huo Liu, Jianzhong ZhangAbstract:A fast three-dimensional (3D) ground penetrating radar (GPR) forward and inverse scattering method is presented based on the Diagonal Tensor approximation (DTA). For the forward scattering problem, the first iteration about the frequency-dependent scattering coefficients in the DTA is used. By further evaluating the scattering Tensor at the GPR center frequency to remove its frequency dependence, the DTA is simplified while maintaining higher accuracy than the classical Born approximation method. For the inverse scattering problem, the DTA-based algorithm is derived for the plane-wave GPR, and can be implemented efficiently by the NUFFT combined with the stabilized bi-conjugate gradient FFT (BiCGS-FFT) method. The proposed inversion algorithm is much cheaper than the existing DTA-based methods, and has a higher accuracy and a wider range of applicability than the fast method based on the Born approximation.
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Three-dimensional electromagnetic nonlinear inversion in layered media by a hybrid Diagonal Tensor approximation: Stabilized biconjugate gradient fast Fourier transform method
Waves in Random and Complex Media, 2007Co-Authors: Baojun Wei, Ergün Şimşek, Qing Huo LiuAbstract:This paper presents an efficient three-dimensional nonlinear electromagnetic inversion method in a multilayered medium for radar applications where the object size is comparable to the wavelength. In the first step of this two-step inversion algorithm, the Diagonal Tensor approximation is used in the Born iterative method. The solution of this approximate inversion is used as an initial guess for the second step in which further inversion is carried out using a distorted Born iterative method. Since the aim of the second step is to improve the accuracy of the inversion, a full-wave solver, the stabilized biconjugate-gradient fast Fourier transform algorithm, is used for forward modelling. The conjugate-gradient method is applied at each inversion iteration to minimize the functional cost. The usage of an iterative solver based on the FFT algorithm and the developed recursive matrix method combined with an interpolation technique to evaluate the layered medium Green's functions rapidly, makes this method h...
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improved Diagonal Tensor approximation dta and hybrid dta bcgs fft method for accurate simulation of 3d inhomogeneous objects in layered media
Waves in Random and Complex Media, 2007Co-Authors: Baojun Wei, E ŝimŝek, Qing Huo LiuAbstract:This paper presents an improved Diagonal Tensor approximation (DTA) and its hybridization with the stabilized biconjugate-gradient fast Fourier transform (BCGS–FFT) algorithm to solve a volume integral equation for three-dimensional (3D) objects in layered media. The improvement in DTA is obtained for lossy media through a higher-order approximation. The interaction between the dyadic Green's function and the contrast source is efficiently evaluated by the (FFT) algorithm through the convolution and correlation theorems. For the hybrid implementation, the DTA solution is used as an initial estimate and a preconditioner in the BCGS–FFT algorithm in order to solve the forwards modelling problem accurately with fewer iterations than the conventional BCGS–FFT algorithm. The accuracy and convergence of the DTA, BCGS–FFT and hybrid DTA/BCGS–FFT methods are compared extensively with several numerical examples. Numerical results show that (a) the improved DTA formulation enhances the accuracy and (b) the DTA/BCGS...
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Improved Diagonal Tensor approximation (DTA) and hybrid DTA/BCGS–FFT method for accurate simulation of 3D inhomogeneous objects in layered media
Waves in Random and Complex Media, 2007Co-Authors: Baojun Wei, E. Ŝimŝek, Qing Huo LiuAbstract:This paper presents an improved Diagonal Tensor approximation (DTA) and its hybridization with the stabilized biconjugate-gradient fast Fourier transform (BCGS–FFT) algorithm to solve a volume integral equation for three-dimensional (3D) objects in layered media. The improvement in DTA is obtained for lossy media through a higher-order approximation. The interaction between the dyadic Green's function and the contrast source is efficiently evaluated by the (FFT) algorithm through the convolution and correlation theorems. For the hybrid implementation, the DTA solution is used as an initial estimate and a preconditioner in the BCGS–FFT algorithm in order to solve the forwards modelling problem accurately with fewer iterations than the conventional BCGS–FFT algorithm. The accuracy and convergence of the DTA, BCGS–FFT and hybrid DTA/BCGS–FFT methods are compared extensively with several numerical examples. Numerical results show that (a) the improved DTA formulation enhances the accuracy and (b) the DTA/BCGS...
Dmitry Valovik - One of the best experts on this subject based on the ideXlab platform.
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Symmetric Guided Electromagnetic Waves in a Plane Anisotropic Dielectric Waveguide
AES20, 2020Co-Authors: Marina Moskaleva, Daria Raschetova, Dmitry Valovik, Ekaterina ZaremboAbstract:In this report we study symmetric guided electromagnetic waves propagating in a plane anisotropic dielectric waveguide. The waveguide has either infinitely conducting walls or open interfaces. In the latter case the waveguide is located between two half-spaces with constant scalar permittivities. The permittivity of the waveguide is given by a real Diagonal Tensor; the permeability is a constant scalar quantity. The dispersion equation is found and studied. Numerical results are presented
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Fully Symmetric Guided Electromagnetic Waves in a Shielded Plane Dielectric Slab
Lobachevskii Journal of Mathematics, 2019Co-Authors: E. O. Biteleva, Daria Raschetova, Dmitry ValovikAbstract:Paper introduces a concept of fully symmetric guided electromagnetic waves. The waves are considered in a plane dielectric slab shielded with infinitely conducting walls. The permittivity of the slab is given by a real Diagonal Tensor; the permeability is a constant scalar quantity. This concept includes particular cases of transverse-electric and transverse-magnetic guided waves as well as novel (more complicated) types of guided waves. The dispersion equation is found and studied. A discussion of possible ways to develop the suggested concept is also given.
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Symmetric guided electromagnetic waves in a shielded slab filled with anisotropic dielectric
2019 Days on Diffraction (DD), 2019Co-Authors: Daria Raschetova, Dmitry ValovikAbstract:In this paper we introduce a concept of symmetric guided electromagnetic waves. The waves are considered in a plane dielectric slab shielded with infinitely conducting walls. The permittivity of the slab is given by a real Diagonal Tensor with positive entries; the permeability is a constant scalar quantity. This concept includes cases of transverse-electric and transverse-magnetic guided waves as well as novel (more complicated) types of guided waves. The dispersion equation is found and its equivalence to the original problem is formulated. Numerical results are presented.
Boram Yoon - One of the best experts on this subject based on the ideXlab platform.
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Flavor Diagonal Tensor charges of the nucleon from (2+1+1)-flavor lattice QCD
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using eleven ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark (HISQ) action with 2+1+1 dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at $M_\pi=135$ MeV. Results for the proton in the $\overline{MS}$ scheme at 2~GeV are: $g_T^u = 0.784(28)(10)$, $g_T^d = -0.204(11)(10)$ and $g_T^s = -0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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flavor Diagonal Tensor charges of the nucleon from 2 1 1 flavor lattice qcd
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using 11 ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark action with $2+1+1$ dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at ${M}_{\ensuremath{\pi}}=135\text{ }\text{ }\mathrm{MeV}$. Results for the proton in the $\overline{\mathrm{MS}}$ scheme at 2 GeV are ${g}_{T}^{u}=0.784(28)(10)$, ${g}_{T}^{d}=\ensuremath{-}0.204(11)(10)$ and ${g}_{T}^{s}=\ensuremath{-}0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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Axial, Scalar and Tensor Charges of the Nucleon from 2+1+1-flavor Lattice QCD
Physical Review D, 2016Co-Authors: Tanmoy Bhattacharya, Rajan Gupta, Vincenzo Cirigliano, Huey-wen Lin, Saul D. Cohen, Boram YoonAbstract:We present results for the isovector axial, scalar and Tensor charges $g^{u-d}_A$, $g^{u-d}_S$ and $g^{u-d}_T$ of the nucleon needed to probe the Standard Model and novel physics. The axial charge is a fundamental parameter describing the weak interactions of nucleons. The scalar and Tensor charges probe novel interactions at the TeV scale in neutron and nuclear $\beta$-decays, and the flavor-Diagonal Tensor charges $g^{u}_T$, $g^{d}_T$ and $g^{s}_T$ are needed to quantify the contribution of the quark electric dipole moment (EDM) to the neutron EDM. The 9 ensembles, generated by the MILC Collaboration using the HISQ action with 2+1+1 dynamical flavors, span three lattice spacings $a \approx 0.06, 0.09$ and 0.12 fm and light-quark masses corresponding to the pion masses $M_\pi \approx 135, 225$ and 315 MeV. High-statistics estimates on five ensembles using the all-mode-averaging method allow us to quantify all systematic uncertainties and perform a simultaneous extrapolation in the lattice spacing, lattice volume and light-quark masses for the connected contributions. Our final estimates, in the $\overline{\text{MS}}$ scheme at 2 GeV, of the isovector charges are $g_A^{u-d} = 1.195(33)(20)$, $g_S^{u-d} = 0.97(12)(6) $ and $g_T^{u-d} = 0.987(51)(20)$. The first error includes statistical and all systematic uncertainties except that due to the extrapolation Ansatz, which is given by the second error estimate. Combining our estimate for $g_S^{u-d}$ with the difference of light quarks masses $(m_d-m_u)^{\rm QCD}=2.67(35)$ MeV given by FLAG, we obtain $(M_N-M_P)^{\rm QCD} = 2.59(49)$ MeV. Estimates of the connected part of the flavor-Diagonal Tensor charges of the proton are $g^{u}_T=0.792(42)$ and $g^{d}_T=-0.194(14)$. Combining our new estimates with precision low-energy experiments, we update constraints on novel scalar and Tensor interactions, $\epsilon_{S,T}$, at the TeV scale.
Rajan Gupta - One of the best experts on this subject based on the ideXlab platform.
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Flavor Diagonal Tensor charges of the nucleon from (2+1+1)-flavor lattice QCD
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using eleven ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark (HISQ) action with 2+1+1 dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at $M_\pi=135$ MeV. Results for the proton in the $\overline{MS}$ scheme at 2~GeV are: $g_T^u = 0.784(28)(10)$, $g_T^d = -0.204(11)(10)$ and $g_T^s = -0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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flavor Diagonal Tensor charges of the nucleon from 2 1 1 flavor lattice qcd
Physical Review D, 2018Co-Authors: Rajan Gupta, Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Yong-chull Jang, Huey-wen LinAbstract:We present state-of-the-art results for the matrix elements of flavor Diagonal Tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using 11 ensembles of gauge configurations generated by the MILC Collaboration using the highly improved staggered quark action with $2+1+1$ dynamical flavors. The calculation of the disconnected contributions is done using seven (six) ensembles for the strange (light) quarks. These high-statistics simulations allowed us to address various systematic uncertainties. A simultaneous fit in the lattice spacing and the light-quark mass is used to extract the Tensor charges in the continuum limit and at ${M}_{\ensuremath{\pi}}=135\text{ }\text{ }\mathrm{MeV}$. Results for the proton in the $\overline{\mathrm{MS}}$ scheme at 2 GeV are ${g}_{T}^{u}=0.784(28)(10)$, ${g}_{T}^{d}=\ensuremath{-}0.204(11)(10)$ and ${g}_{T}^{s}=\ensuremath{-}0.0027(16)$. Implications of these results for constraining the quark electric dipole moments and their contributions to the neutron electric dipole moment are discussed.
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Axial, Scalar and Tensor Charges of the Nucleon from 2+1+1-flavor Lattice QCD
Physical Review D, 2016Co-Authors: Tanmoy Bhattacharya, Rajan Gupta, Vincenzo Cirigliano, Huey-wen Lin, Saul D. Cohen, Boram YoonAbstract:We present results for the isovector axial, scalar and Tensor charges $g^{u-d}_A$, $g^{u-d}_S$ and $g^{u-d}_T$ of the nucleon needed to probe the Standard Model and novel physics. The axial charge is a fundamental parameter describing the weak interactions of nucleons. The scalar and Tensor charges probe novel interactions at the TeV scale in neutron and nuclear $\beta$-decays, and the flavor-Diagonal Tensor charges $g^{u}_T$, $g^{d}_T$ and $g^{s}_T$ are needed to quantify the contribution of the quark electric dipole moment (EDM) to the neutron EDM. The 9 ensembles, generated by the MILC Collaboration using the HISQ action with 2+1+1 dynamical flavors, span three lattice spacings $a \approx 0.06, 0.09$ and 0.12 fm and light-quark masses corresponding to the pion masses $M_\pi \approx 135, 225$ and 315 MeV. High-statistics estimates on five ensembles using the all-mode-averaging method allow us to quantify all systematic uncertainties and perform a simultaneous extrapolation in the lattice spacing, lattice volume and light-quark masses for the connected contributions. Our final estimates, in the $\overline{\text{MS}}$ scheme at 2 GeV, of the isovector charges are $g_A^{u-d} = 1.195(33)(20)$, $g_S^{u-d} = 0.97(12)(6) $ and $g_T^{u-d} = 0.987(51)(20)$. The first error includes statistical and all systematic uncertainties except that due to the extrapolation Ansatz, which is given by the second error estimate. Combining our estimate for $g_S^{u-d}$ with the difference of light quarks masses $(m_d-m_u)^{\rm QCD}=2.67(35)$ MeV given by FLAG, we obtain $(M_N-M_P)^{\rm QCD} = 2.59(49)$ MeV. Estimates of the connected part of the flavor-Diagonal Tensor charges of the proton are $g^{u}_T=0.792(42)$ and $g^{d}_T=-0.194(14)$. Combining our new estimates with precision low-energy experiments, we update constraints on novel scalar and Tensor interactions, $\epsilon_{S,T}$, at the TeV scale.