scholarly journals In-Medium Strangeness Production and Hyperon-Potentials

2019 ◽  
Vol 26 ◽  
pp. 83
Author(s):  
T. Gaitanos ◽  
A. Violaris ◽  
L. Fabbietti ◽  
M. Steffen ◽  
J. Wirth

A hot topic of current research concerns the Equation of State (EoS) of nucleons and, in particular, of hyperons in dense nucleonic media. The study of the EoS at nucleon densities far beyond saturation has been initiated several decades ago, however, the behavior of the EoS for strangeness particles is still an open issue. The strangeness part of the EoS is very important not only for the physics of exotic (hyper)nuclei, but also crucial for nuclear astrophysics, e.g., neutron star physics.Here we present our recent investigations related to the theoretical treatment of in-medium hyperon-interactions as well as first preliminary experimental results from pion-induced reactions. The theoretical study is based on the well-established Non-Linear Derivative (NLD) model, which is extended to the strangeness sector via SU(6) symmetry arguments. It turns out that the NLD-predictions are consistent with microscopic models based on the chiral-EFT theory. On the other hand, recent experimental HADES-data on hyperon and kaon production from pion-induced reactions indicate sensitivities on the underlying in-medium hyperon potentials. We thus conclude that, the recent experimental data from pion-induced reactions will definitely set stringent constraints on the still less understood hyperon-potentials in nucleonic matter.

2010 ◽  
Vol 20 (3) ◽  
pp. 193
Author(s):  
Doan Nhat Quang ◽  
Nguyen Huyen Tung ◽  
Nguyen Trung Hong ◽  
Tran Thi Hai

We present a theoretical study of the effects from symmetric modulation of the envelop wave function on quantum transport in square quantum wells (QWs). Within the variational approach we obtain analytic expressions for the carrier distribution and their scattering in symmetric two-side doped square QWs. Roughness-induced scattering are found significantly weaker than those in the asymmetric one-side doped counterpart. Thus, we propose symmetric modulation of the wave function as an efficient method for enhancement of the roughness-limited QW mobility. Our theory is able to well reproduce the recent experimental data about low-temperature transport of electrons and holes in two-side doped square QWs, e.g., the mobility dependence on the channel width, which have not been explained so far.


Author(s):  
Shun Yao

Chiral stationary phases (CSPs) and molecular structure of enantiomers are two independent but related aspects in enantioseparation, which are discussed on the basis of the experimental data from the previous study. Two enantioseparation experiments are performed to illustrate the relationship between enantiomer structures and chiral stationary phases, one is the resolution of mandelic acid derivatives and the other is about prasugrel. Thermodynamic mechanism and theoretical study with computational chemistry method is helpful to understand the interactions of enantiomer and CSPs.


2015 ◽  
Vol 11 (2) ◽  
pp. 2972-2978
Author(s):  
Fouad A. Majeed ◽  
Yousif A. Abdul-Hussien

In this study the calculations of the total fusion reaction cross section have been performed for fusion reaction systems 17F + 208Pb and 15C + 232Th which involving halo nuclei by using a semiclassical approach.The semiclassical treatment is comprising the WKB approximation to describe the relative motion between target and projectile nuclei, and Continuum Discretized Coupled Channel (CDCC) method to describe the intrinsic motion for both target and projectile nuclei. For the same of comparsion a full quantum mechanical clacualtions have been preforemd using the (CCFULL) code. Our theorticalrestuls are compared with the full quantum mechaincialcalcuations and with the recent experimental data for the total fusion reaction  checking the stability of the distancesThe coupled channel calculations of the total fusion cross section σfus, and the fusion barrier distribution Dfus. The comparsion with experiment proves that the semiclassiacl approach adopted in the present work reproduce the experimental data better that the full quantal mechanical calcautions. 


Author(s):  
Antony N. Beris ◽  
Brian J. Edwards

This much-needed monograph presents a systematic, step-by-step approach to the continuum modeling of flow phenomena exhibited within materials endowed with a complex internal microstructure, such as polymers and liquid crystals. By combining the principles of Hamiltonian mechanics with those of irreversible thermodynamics, Antony N. Beris and Brian J. Edwards, renowned authorities on the subject, expertly describe the complex interplay between conservative and dissipative processes. Throughout the book, the authors emphasize the evaluation of the free energy--largely based on ideas from statistical mechanics--and how to fit the values of the phenomenological parameters against those of microscopic models. With Thermodynamics of Flowing Systems in hand, mathematicians, engineers, and physicists involved with the theoretical study of flow behavior in structurally complex media now have a superb, self-contained theoretical framework on which to base their modeling efforts.


2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Wen Qin ◽  
Ling-Yun Dai ◽  
Jorge Portolés

Abstract A coherent study of e+e− annihilation into two (π+π−, K+K−) and three (π+π−π0, π+π−η) pseudoscalar meson production is carried out within the framework of resonance chiral theory in energy region E ≲ 2 GeV. The work of [L.Y. Dai, J. Portolés, and O. Shekhovtsova, Phys. Rev. D88 (2013) 056001] is revisited with the latest experimental data and a joint analysis of two pseudoscalar meson production. Hence, we evaluate the lowest order hadronic vacuum polarization contributions of those two and three pseudoscalar processes to the anomalous magnetic moment of the muon. We also estimate some higher-order additions led by the same hadronic vacuum polarization. Combined with the other contributions from the standard model, the theoretical prediction differs still by (21.6 ± 7.4) × 10−10 (2.9σ) from the experimental value.


2004 ◽  
Vol 18 (09) ◽  
pp. 1351-1368
Author(s):  
ANDREI DOLOCAN ◽  
VOICU OCTAVIAN DOLOCAN ◽  
VOICU DOLOCAN

Using a new Hamiltonian of interaction we have calculated the cohesive energy in three-dimensional structures. We have found the news dependences of this energy on the distance between the atoms. The obtained results are in a good agreement with experimental data in ionic, covalent and noble gases crystals. The coupling constant γ between the interacting field and the atoms is somewhat smaller than unity in ionic crystals and is some larger than unity in covalent and noble gases crystals. The formulae found by us are general and may be applied, also, to the other types of interactions, for example, gravitational interactions.


2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Eduard Amromin

According to several known experiments, an increase of the incoming flow air content can increase the hydrofoil lift coefficient. The presented theoretical study shows that such increase is associated with the decrease of the fluid density at the cavity surface. This decrease is caused by entrainment of air bubbles to the cavity from the surrounding flow. The theoretical results based on such explanation are in a good agreement with the earlier published experimental data for NACA0015.


2011 ◽  
Vol 78 (2) ◽  
pp. 165-174 ◽  
Author(s):  
C. L. XAPLANTERIS ◽  
E. D. FILIPPAKI ◽  
I. S. MISTAKIDIS ◽  
L. C. XAPLANTERIS

AbstractMany experimental data along with their theoretical interpretations on the rf low-temperature cylindrical plasma have been issued until today. Our Laboratory has contributed to that research by publishing results and interpretative mathematical models. With the present paper, two issues are being examined; firstly, the estimation of electron drift caused by the rf field gradient, which is the initial reason for the plasma behaviour, and secondly, many new experimental results, especially the electron-neutral collision frequency effect on the other plasma parameters and quantities. Up till now, only the plasma steady state was taken into consideration when a theoretical elaboration was carried out, regardless of the cause and the effect. This indicates the plasma's complicated and chaotic configuration and the need to simplify the problem. In the present work, a classification about the causality of the phenomena is attempted; the rf field gradient electron drift is proved to be the initial cause.


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