English
Related papers

Related papers: QCD sum rules for the $\Delta$ isobar in neutron m…

200 papers

We compute the diagonal isovector axial-vector as well as induced pseudoscalar form factors of nucleon, $\Sigma$ and $\Xi$ baryons by employing the light-cone QCD sum rules to leading order in QCD and including distribution amplitudes up to…

High Energy Physics - Phenomenology · Physics 2011-06-24 Guray Erkol , Altug Ozpineci

The symmetry energy expansion was developed to connect isospin symmetric matter probed in nuclear experiments to asymmetric matter found in neutron stars. Using the isospin asymmetry derived from the Gell-Mann-Nishijima formula, we derive…

Nuclear Theory · Physics 2025-10-29 Isabella Danhoni , Yumu Yang , Mauricio Hippert , Jacquelyn Noronha-Hostler

The QCD sum rule approach is employed in order to study chiral properties of positive- and negative-parity nucleon resonances. It is pointed out that nucleons with an ``exotic'' chiral property, which can be represented by local five-quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Nakamura , P. Gubler , M. Oka

Using a recently developed three-point formalism within the method of QCD Sum Rules we determine the vacuum susceptibilities needed in the two-point formalism for the coupling of axial, vector, tensor and pseudoscalar currents to hadrons.…

High Energy Physics - Phenomenology · Physics 2009-10-31 Leonard S. Kisslinger

A current-current correlator with the quantum numbers of the omega meson is studied in a nuclear medium. Using weighted finite energy sum rules and dispersion relations for the current-nucleon forward scattering amplitude it is shown that…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Leupold

Pseudo-scalar and scalar $D$ mesons are considered within the QCD sum rule approach. We present an analysis of the mass splitting of the pseudo-scalar D - D-bar mesons and the relation to QCD condensates. Weinberg type sum rules are derived…

Nuclear Theory · Physics 2010-02-18 T. Hilger , B. Kampfer

We emphasize the role of the x dependence of the quark condensate <|\bar q(0)q(x)|> originated by the zero fermion modes in the instanton vacuum. The effect is not negligible since the inverse size of the instanton 1/\rho~600MeV is…

High Energy Physics - Phenomenology · Physics 2014-07-21 M. G. Ryskin , V. A. Sadovnikova

Extending a recent suggestion for hyperon form factors to the nucleon case, dispersion theory is used to relate the low-energy vector-isovector form factors of the nucleon to the pion vector form factor. The additionally required input,…

High Energy Physics - Phenomenology · Physics 2018-02-14 Stefan Leupold

In this work we evaluate the imaginary part of the isobar $\Delta$ self-energy $\Sigma_{\Delta}$ from the two-body absorption process $\Delta+N\rightarrow 2N$. This contribution is calculated using a recently developed non-relativistic…

Nuclear Theory · Physics 2008-11-26 M. Hjorth-Jensen , H. Müther , A. Polls

A new QCD calculation of the mass of the nucleon is presented. It makes use of a polynomial kernel in the dispersion integrals tailored to practically eliminate the contribution of the unknown 1/2+ and 1/2- continuum. This approach avoids…

High Energy Physics - Phenomenology · Physics 2010-11-03 N. F. Nasrallah , K. Schilcher

In this article, we assume that the nonet scalar mesons below $1\,\rm{ GeV}$ are the two-quark-tetraquark mixed states and study their masses and pole residues using the QCD sum rules. In calculation, we take into account the vacuum…

High Energy Physics - Phenomenology · Physics 2016-08-02 Zhi-Gang Wang

Working on the framework of Relativistic Mean Field theory, we exposed the effect of nonlinear isoscalar-isovector coupling on G2 parameter set on the density dependence of nuclear symmetry energy in infinite nuclear matter. The observables…

Nuclear Theory · Physics 2015-06-12 S. K. Singh , M. Bhuyan , P. K. Panda , S. K. Patra

The influence of $\Delta$ isobar components on the ground state properties of nuclear systems is investigated for nuclear matter as well as finite nuclei. Many-body wave functions, including isobar configurations, and binding energies are…

Nuclear Theory · Physics 2009-11-07 T. Frick , S. Kaiser , H. Müther , A. Polls , D. R. Entem , R. Machleidt

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 investigate in detail the density dependence of the symmetry energy in a relativistic description by decomposing the iso-vector mean field into contributions with different Lorentz covariant properties. We find important effects of the…

Nuclear Theory · Physics 2008-11-26 T. Gaitanos , M. Di Toro , S. Typel , V. Baran , C. Fuchs , V. Greco , H. H. Wolter

It was found that the isoscalar-scalar and isovector-scalar mesons play significant roles in nuclear matter physics. However, the underlying structures of these resonances are not yet well understood. We construct a three-flavor baryonic…

Nuclear Theory · Physics 2024-04-18 Yao Ma , Yong-Liang Ma

We analyse the calculations of deep inelastic structure functions of free nucleons by QCD sum rules method,carried out by others.We present our results of calculation of the distribution of valence quarks in nucleon placed into the nuclear…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. G. Drukarev

We investigate the static properties of the nucleon in the presence of strong magnetic fields and discuss the consequent changes of the nucleon structure, based on the Skyrme model. The results show that at large values of the magnetic…

High Energy Physics - Phenomenology · Physics 2019-04-03 Ulugbek Yakhshiev , Hyun-Chul Kim , Makoto Oka

It is widely known that the nucleon scalar charge is proportional to the pion-nucleon sigma term as one of the important low energy observables of QCD. Especially interesting to us is the physics of the nucleon scalar charge densities. This…

High Energy Physics - Phenomenology · Physics 2025-02-06 Masashi Wakamatsu

We use QCD sum rules for the three point function of a pseudoscalar and two nucleonic currents in order to estimate the charge dependence of the pion nucleon coupling constant $g_{NN\pi}$ coming from isospin violation in the strong…

Nuclear Theory · Physics 2008-11-26 T. Meissner , E. M. Henley