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Results are presented on the neutron electric dipole moment using an ensemble of $N_f=2+1+1$ twisted mass clover-improved fermions with lattice spacing of $a\simeq 0.08$ fm and physical pion mass ($m_\pi\simeq 139$ MeV). The approach…

High Energy Physics - Lattice · Physics 2021-12-14 Constantia Alexandrou , Andreas Athenodorou , Kyriakos Hadjiannakou , Antonino Todaro

We present results from a lattice QCD study of nucleon matrix elements at vanishing momentum transfer for local and twist-2 isovector operator insertions. Computations are performed on gauge ensembles with non-perturbatively improved…

We present a calculation of the contribution of the $\Theta$-term to the neutron and proton electric dipole moments using seven 2+1+1-flavor HISQ ensembles. We also estimate the topological susceptibility for the 2+1+1 theory to be $\chi_Q…

High Energy Physics - Lattice · Physics 2021-06-16 Tanmoy Bhattacharya , Vincenzo Cirigliano , Rajan Gupta , Emanuele Mereghetti , Boram Yoon

We present preliminary results for the contributions to the neutron EDM arising from the QCD $\theta$-term, the Weinberg three-gluon and the quark chromo-EDM operators from our ongoing lattice calculations using clover valence quarks on the…

High Energy Physics - Lattice · Physics 2020-03-12 Boram Yoon , Tanmoy Bhattacharya , Vincenzo Cirigliano , Rajan Gupta

We present results from our lattice QCD study of the contribution of the isovector quark cEDM (qcEDM) operator to the neutron EDM. The calculation was carried out on four 2+1+1-flavor highly improved staggered quark ensembles (provided to…

High Energy Physics - Lattice · Physics 2024-04-23 Tanmoy Bhattacharya , Vincenzo Cirigliano , Rajan Gupta , Emanuele Mereghetti , Jun-Sik Yoo , Boram Yoon

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…

High Energy Physics - Lattice · Physics 2017-01-17 Tanmoy Bhattacharya , Vincenzo Cirigliano , Saul Cohen , Rajan Gupta , Huey-Wen Lin , Boram Yoon

We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP odd form factor F_3. A novel feature of our…

High Energy Physics - Lattice · Physics 2008-08-15 R. Horsley , T. Izubuchi , Y. Nakamura , D. Pleiter , P. E. L. Rakow , G. Schierholz , J. Zanotti

We briefly discuss the current status of lattice QCD simulations and review selective results on nucleon observables focusing on recent developments in the lattice QCD evaluation of the nucleon form factors and radii, parton distribution…

High Energy Physics - Lattice · Physics 2017-04-05 Constantia Alexandrou

The nucleon tensor charge, $g_T$, is an important quantity in the search for beyond the Standard Model tensor interactions in neutron and nuclear $\beta$-decays as well as the contribution of the quark electric dipole moment (EDM) to the…

High Energy Physics - Lattice · Physics 2021-12-13 R. E. Smail , R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

Using the QCD sum rule approach, we calculate the electric dipole moment of the neutron induced by a vacuum theta--angle to approximately 40-50% precision, d_n = 2.4 x 10^{-16} \theta e.cm. Combined with the new experimental bound, this…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Pospelov , A. Ritz

We present lattice-QCD results on the nucleon isovector axial, scalar and tensor charges, the isovector electromagnetic Dirac and Pauli form factors, and the connected parts of the isoscalar charges. The calculations have been done using…

High Energy Physics - Lattice · Physics 2014-05-14 Tanmoy Bhattacharya , Saul D. Cohen , Rajan Gupta , Anosh Joseph , Huey-Wen Lin , Boram Yoon

We present an update on our calculations of the matrix elements of the CP violating quark and gluon chromo-EDM operators, as well as the operators these mix with, such as the QCD Theta-term. Their contribution to the neutron EDM is obtained…

High Energy Physics - Lattice · Physics 2018-12-18 Tanmoy Bhattacharya , Boram Yoon , Rajan Gupta , Vincenzo Cirigliano

We demonstrate how to make rigorous predictions for electroweak matrix elements in nuclear systems directly from QCD. More precisely, we show how to determine the short-distance contributions to low-momentum transfer electroweak matrix…

High Energy Physics - Lattice · Physics 2009-11-10 William Detmold , Martin J. Savage

Results are presented for the nucleon isovector electromagnetic form factors using 11 ensembles generated by the MILC collaboration using the 2+1+1-flavors HISQ action. They span 4 lattice spacings $a \sim$ 0.06, 0.09, 0.12 and 0.15~fm and…

High Energy Physics - Lattice · Physics 2020-01-29 Yong-Chull Jang , Rajan Gupta , Huey-Wen Lin , Boram Yoon , Tanmoy Bhattacharya

Interpretation of current and future neutrino oscillation and electron scattering experiments requires knowledge of lepton-nucleon and lepton-nucleus interactions at the percent level. We study the exchange of photons between charged…

Nuclear Theory · Physics 2022-10-19 Oleksandr Tomalak , Ivan Vitev

We use the energy-momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon's interpolating…

High Energy Physics - Phenomenology · Physics 2020-03-18 K. Azizi , U. Ozdem

We present a detailed study of the electric dipole moment of the neutron induced by a vacuum theta angle within the framework of QCD sum rules. At next-to-next-to leading order in the operator product expansion, we find the result…

High Energy Physics - Phenomenology · Physics 2009-10-31 Maxim Pospelov , Adam Ritz

Interaction with the axion dark matter (DM) field generates an oscillating nuclear electric dipole moment (EDM) with a frequency corresponding to the axion's Compton frequency. Within an atom, an oscillating EDM can drive electric dipole…

Atomic Physics · Physics 2019-09-12 Victor V. Flambaum , Dmitry Budker , Arne Wickenbrock

In any finite system, the presence of a non-zero permanent electric dipole moment (EDM) would indicate CP violation beyond the small violation predicted in the Standard Model. Here, we use the ab initio no-core shell model (NCSM) framework…

Nuclear Theory · Physics 2021-08-23 Paul Froese , Petr Navratil

Electromagnetic transitions involving nucleons and their resonances are here presented in the fermionic sector of the AdS/QCD soft-wall model, using the differential configurational entropy (DCE) as a measure of information entropy. The DCE…

High Energy Physics - Theory · Physics 2023-05-18 Roldao da Rocha