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Related papers: The $A_y$ Puzzle and the Nuclear Force

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The hyperon puzzle refers to the challenge of reconciling the existence of hyperons in neutron star cores and the observed high masses of neutron stars. The recent discovery of PSR J0952-0607 ($2.35\pm0.17 M_{\odot}$) has intensified this…

Nuclear Theory · Physics 2026-03-10 Hao-Fu Zhu , Guo-Zhu Liu , Xufen Wu , Ye-Fei Yuan

The so-called hyperon puzzle in the theory of neutron stars is considered in the framework of modified $f(R)$ gravity. We show that for simple hyperon equations of state, it is possible to obtain the maximal neutron star mass which…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

Microscopic calculations of four-body collisions become very challenging in the energy regime above the threshold for four free particles. The neutron-${}^3$He scattering is an example of such process with elastic, rearrangement, and…

Nuclear Theory · Physics 2017-06-05 A. Deltuva , A. C. Fonseca

The traditional nuclear shell model approach is extended to include many-body forces. The empirical Hamiltonian with a three-body force is constructed for the identical nucleons on the 0f7/2 shell. Manifestations of the three-body force in…

Nuclear Theory · Physics 2009-08-03 Alexander Volya

We report on a microscopic Refined Resonating Group Model (RRGM) calculation of scattering of $p$ off ${}^3{\rm He}$ employing the Argonne-$v_{14}$ and the Bonn nucleon-nucleon potentials without three-nucleon forces at low energies up to…

Nuclear Theory · Physics 2009-11-10 C. Reiss , H. M. Hofmann

Electro-disintegration of the deuteron at large $Q^2$ currently represents on of the most promising reactions which allows to probe the bound nuclear state at internal momenta comparable to the rest mass of the nucleon. Large internal…

Nuclear Theory · Physics 2024-02-22 Misak M Sargsian

The long-range terms of the subleading chiral three-nucleon force [published in Phys.\,Rev.\,C77, 064004 (2008)] are specified to the case of three neutrons. From these $3n$-interactions an effective density-dependent neutron-neutron…

Nuclear Theory · Physics 2020-12-21 N. Kaiser

A new computational method for solving the nucleon-deuteron breakup scattering problem has been applied to study the elastic neutron- and proton-deuteron scattering on the basis of the configuration-space Faddeev-Noyes-Noble-Merkuriev…

Nuclear Theory · Physics 2010-06-10 V. M. Suslov , M. A. Braun , I. N. Filikhin , B. Vlahovic , I. Slaus

We present measurements of differential cross sections and the analyzing powers A_y, iT11, T20, T21, and T22 at E_c.m.=431.3 keV. In addition, an excitation function of iT11(theta_c.m.=87.8 degrees) for 431.3 <= E_c.m. <= 2000 keV is…

Nuclear Experiment · Physics 2009-10-31 C. R. Brune , W. H. Geist , H. J. Karwowski , E. J. Ludwig , K. D. Veal , M. H. Wood , A. Kievsky , S. Rosati , M. Viviani

Background: Modern ab initio theory combined with high-quality nucleon-nucleon (NN) and three-nucleon (3N) interactions from chiral effective field theory (EFT) can provide a predictive description of low-energy light-nuclei reactions…

An accurate assessment of the hyperon-nucleon interaction is of great interest in view of recent observations of very massive neutron stars. The challenge is to build a realistic interaction that can be used over a wide range of masses and…

Nuclear Theory · Physics 2014-01-22 Diego Lonardoni , Francesco Pederiva , Stefano Gandolfi

As follows from the energies of single-particle states in ^{40}Ca, ^{90}Zr and ^{208}Pb nuclei the contribution of many-particle NN forces to the nuclear single-particle potential is at least the sum of repulsive and attractive parts…

Nuclear Theory · Physics 2007-05-23 B. L. Birbrair , V. I. Ryazanov

The clustering of nucleons is a fundamental phenomenon with broad implications for nuclear physics and astrophysics. In this work, we employ a microscopic in-medium few-body approach to systematically investigate the formation and…

Nuclear Theory · Physics 2026-01-14 Qi Meng , Chang Xu

Lattice QCD is making good progress toward calculating the structure and properties of light nuclei and the forces between nucleons. These calculations will ultimately refine the nuclear forces, particularly in the three- and four-nucleon…

High Energy Physics - Lattice · Physics 2016-11-08 Martin J. Savage

The effective field theory approach is applied to the three-nucleon process of $S=1/2$ neutron-deuteron scattering in the S-wave, including the effective range parameters summed at all orders. This is achieved through a modification of the…

Nuclear Theory · Physics 2007-05-23 F. Gabbiani

The consideration is presented of possible neutron experiments to search for new short-range spin-dependent forces. The spin-dependent nucleon-nucleon interaction between neutron and nuclei may cause different effects: phase shift of a…

Nuclear Experiment · Physics 2015-05-28 Yu. N. Pokotilovski

The three-nucleon system is studied at energies a few hundred keV above the N-d threshold. Measurements of the tensor analyzing powers $T_{20}$ and $T_{21}$ for p-d elastic scattering at $E_{c.m.}=432$ keV are presented together with the…

Nuclear Theory · Physics 2009-10-30 A. Kievsky , S. Rosati , M. Viviani , C. R. Brune , H. J. Karwowski , E. J. Ludwig , M. H. Wood

We explore the effects of a microscopic nuclear three-body force on the threshold baryon density for kaon condensation in chemical equilibrium neutron star matter and on the composition of the kaon condensed phase in the framework of the…

Nuclear Theory · Physics 2008-11-26 W. Zuo , A. Li , Z. H. Li , U. Lombardo

We present a precise measurement of the cross section, proton and $\rm ^3He$ analyzing powers, and spin correlation coefficient $C_{y,y}$ for $p$-$\rm ^3He$ elastic scattering near 65 MeV, and a comparison with rigorous four-nucleon…

We propose a simplified approach to incorporate the long-range proton-proton (pp) Coulomb force in the three-nucleon (3N) scattering calculations, based on exact formulation presented in Eur. Phys. Journal A {\bf{41}}, 369 (2009) and…

Nuclear Theory · Physics 2023-10-06 H. Witała , J. Golak , R. Skibiński