Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 1405.1997

Particle production in antiproton induced nuclear reactions

Zhao-Qing Feng·Horst Lenske
View original source ↗Read source document ↗Export metadata ↓

Abstract

The quantum molecular dynamics model has been improved to investigate the reaction dynamics induced by antiprotons. The reaction channels of elastic scattering, annihilation, charge exchange and inelastic collisions have been included in the model. Dynamics on particle production, in particular pions, kaons, antikaons and hyperons, is investigated in collisions of $\overline{p}$ on $^{12}$C, $^{20}$Ne, $^{40}$Ca, $^{112}$Sn, $^{181}$Ta, $^{197}$Au and $^{238}$U from a low to high incident momentum. The rapidity and momentum distributions of $π^{+}$ and protons from the LEAR measurements can be well reproduced. The impacts of system size and incident momentum on particle emissions are investigated from the inclusive spectra, transverse momentum and rapidity distributions. It is found that the annihilations of $\overline{p}$ on nucleons are of importance on the particle production. Hyperons are mainly produced via meson induced reactions on nucleons and strangeness exchange collisions when the incident momentum is below the threshold value of annihilation reaction. A higher nuclear temperature is obtained from the kaon emission, but it has a lower value for hyperon production.

Explore related subjects

nucl-th

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Zhao-Qing Feng, Horst Lenske. 2014-05-07. Particle production in antiproton induced nuclear reactions. https://doi.org/10.1103/physrevc.89.044617

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

KEEP EXPLORING

Related papers

arXiv2026

Reformulation of the pionless effective field theory for practical few- and many-body applications

The effective field theory (EFT) of contact forces which describes few-nucleon systems at distance scales larger than the pion Compton wavelength ${\rm EFT}({π\hskip-0.54em /})$ can be defined in terms of momentum-dependent potentials that contain a fixed number of simple poles and generate the effective-range expansion to a given fixed order. These potentials provide a practical generalization of the standard ${\rm EFT}({π\hskip-0.54em /})$ power-counting scheme which, for instance, naturally accounts for the large effective ranges in the s-wave channels. Nucleon-nucleon phase shifts computed in this formulation of ${\rm EFT}({π\hskip-0.54em /})$ are compared to modern phase-shift analyses, and effective-range parameters are tabulated. The ${\rm EFT}({π\hskip-0.54em /})$ potentials, which provide a rational approximation of the S-matrix, are easily extended into the regime of pion physics through the inclusion of additional S-matrix poles and zeros, and provide an accurate description of data up to pion-production threshold. The potentials in this scheme are in an important sense weak over all relevant distance scales, and are therefore of utility for systematic calculations of many-nucleon observables.

nucl-th↗
arXiv2026

Spatial asymmetry of neutron pairing:A distance-resolved study of $^{46}\mathrm{Ti}$

Distance integration can conceal the spatial organization of neutron pairing in a reflection-asymmetric intrinsic configuration. We resolve the spin-singlet pairing tensor by relative distance and signed pair-center position along a prescribed $α$+$^{42}$Ca-like path in $^{46}$Ti, using density-constrained Skyrme Hartree--Fock plus Bardeen--Cooper--Schrieffer calculations. Compact and extended components have oppositely signed shifts relative to the normal-density product conditioned on the same distance interval. At a reference center separation of 6 fm, the distance-integrated difference is 0.010, whereas the compact--extended contrast is 0.439. For the baseline surface-pairing prescription, this contrast increases between reference center separations of 6 and 7 fm while the extended anomalous weight decreases and the average neutron gap increases. Endpoint partitions locate an excess of extended neutron weight with both nucleons on the core side. An interference-retaining analysis in the stored canonical representation links the anomalous redistribution to $f_{7/2}$-weighted branches gaining core-side support with distinct amplitude responses. Changes in the normal-density reference contribute separately to the growing contrast. The conditional neutron pattern persists under the tested functional and pairing variations. Distance-conditioned distributions thus reveal intrinsic pairing structure hidden by scalar measures and distance integration.

nucl-th↗
arXiv2026

Hybrid Stars with a Crossover Equation of State

The possible occurrence of a phase transition in superdense nuclear matter remains an open problem in nuclear physics. In particular, the transition from purely hadronic matter to the hypothesized deconfined quark matter is a subject of considerable interest. Beyond its fundamental significance, this transition has important implications for the physics of compact objects, including neutron stars, quark stars, and hybrid stars. The conventional approaches to this problem involve the Maxwell and Gibbs constructions, both of which have been extensively studied and applied. In the present study, we focus on a third, alternative approach based on a smooth transition from hadronic to quark matter through the so-called switching function. More specifically, the present work focuses on two main objectives. The first is to systematically investigate the influence of the symmetry energy on the transition densities and chemical potentials associated with the transition to quark matter. Subsequently, we attempt to physically constrain and parametrize the two parameters characterizing the switching function, ensuring that the transition from hadronic to quark matter is not merely continuous but also consistent with relevant physical requirements. The main conclusion is that, with an appropriate choice of the aforementioned parameters, the phenomenological model becomes more physically motivated and can serve as a useful tool for investigating the structure and properties of hybrid compact objects. Moreover, this approach offers the flexibility to predict the properties of compact objects that lie beyond the scope of standard neutron-star theory, such as objects characterized by relatively low masses and small radii, which have recently attracted considerable attention in observational studies.

nucl-th↗