Searcharxiv⌕ Search

arXiv · nucl-th/0311089

Dispersion Relation Constrained Partial Wave Analysis of piN Elastic and piN\to\etaN Scattering Data: The Baryon Spectrum

Abstract

We present results from a comprehensive partial-wave analysis of pi+-p elastic scattering and charge-exchange data, covering the region from threshold to 2.1 GeV in the lab pion kinetic energy, employing a coupled-channel formalism to simultaneously fit pi-p\toηn data to 0.8 GeV. Our main result, solution FA02, utilizes a complete set of forward and fixed-t dispersion relation constraints, from threshold to 1 GeV, and from t = 0 to -0.4 (GeV/c)^2, applied to the piN elastic amplitude. A large number of systematic checks have been performed, including fits with no charge-exchange data and other database changes, fits with few or no dispersion relation constraints, and changes to the Coulomb correction scheme. We have also reexamined methods used to extract Breit-Wigner resonance parameters. The quality of fit to both data and dispersion relation constraints is superior to our earlier work. The results of these analyses are compared with previous solutions in terms of their resonance spectra and preferred values for couplings and low-energy parameters, including the piNN coupling constant.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R. A. Arndt, W. J. Briscoe, I. I. Strakovsky, R. L. Workman, M. M. Pavan. 2004-01-23. Dispersion Relation Constrained Partial Wave Analysis of piN Elastic and piN\to\etaN Scattering Data: The Baryon Spectrum. https://doi.org/10.1103/physrevc.69.035213

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Bayesian inference of the dense matter equation of state built upon extended Skyrme interactions: A generalization

The nonrelativistic theory of nuclear matter (NM) based on Brussels-Skyrme interactions is employed to develop models for dense and neutron-rich matter within a Bayesian framework. We employ the following set of constraints: the four best-known nuclear empirical parameters, the density dependence of the energy per particle in pure neutron matter (PNM), the density dependence of the Landau effective mass ($m_\mathrm{eff}$) of neutrons in PNM and symmetric NM, and a lower limit on the maximum gravitational mass that neutron stars (NSs) can support. In addition, a number of ``sanity checks'' are added: the values of the speed of sound, neutron and proton Landau effective masses, and Fermi velocities are constrained up to the central density of the most massive NS configuration and for isospin asymmetries $δ=(n_n-n_p)/(n_n+n_p)$ ranging from 0 to 1. Our ensemble of models \emph{fully} explores the capacity of nonrelativistic Brussels-Skyrme effective interactions to describe NM at densities exceeding several times the nuclear saturation density. This is a necessary step toward a better understanding of the properties of dense matter and possible correlations between the parameters of NSs and the parameters of NM. Due to the pronounced U-shaped density dependencies of $m_\mathrm{eff}$, which qualitatively agree with the predictions of ab initio calculations featuring three-body forces, all our models exhibit a non-monotonic ``rise-and-fall'' behavior of the thermal pressure ($p_\mathrm{th}$) as a function of density, which in extreme cases leads to $p_\mathrm{th} < 0$. This work is a generalization of [Beznogov and Raduta, Phys. Rev. C 110, 035805 (2024)].

nucl-th↗

Is XTE J1814-338 a dark matter-admixed neutron star?

We explore the possibility that the ultracompact object XTE J1814-338 is a dark matter-admixed neutron star (DNS) based on a general-relativistic two-fluid approach, in which one fluid describes ordinary nuclear matter and the other dark matter. The equations of state of nuclear matter and dark matter are described by the Brueckner-Hartree-Fock (BHF) theory with realistic three-body forces and a generic bosonic self-interacting dark matter model, respectively. Based on the observational data, we determine the parameter space for XTE J1814-338 as a DNS, and find that only a halo stellar configuration with a high dark matter fraction is allowed. Furthermore, we predict other observable properties of XTE J1814-338 and provide robust lower bounds for these quantities.

nucl-th↗

The role of spin polarization in event-by-event fluctuations

The event-by-event initial state fluctuations constitute a critical physical quantity for understanding the dynamics of high-energy heavy-ion collisions. Due to the extremely limited available experimental data of such fluctuations, it is difficult to constrain or direct the characterization of the underlying initial state properties. This work constrains the correlation function between the initial eccentricity and the asymmetry by employing a parton distribution function that incorporates spin polarization induced by thermal vorticity and thermal shear. Based on the kinetic theory calculations, we found that the asymmetry fluctuations considering spin polarization have a significant splitting effect compared to those without spin polarization. These splitting exhibit pronounced system size and energy dependence. Moreover, the ratios of correlation function display similar system size and energy dependence--particularly in the low-temperature regime ($T \lesssim$ 0.12 GeV). These results suggest that spin polarization may serve as a useful constraint method for the event-by-event initial state fluctuations of heavy-ion collisions.

nucl-th↗