Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userBaryonic matter and the medium modification of the baryon masses
81
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We investigate the properties of baryonic matter within the framework of the in-medium modified chiral soliton model by taking into account the effects of surrounding baryonic environment on the properties of in-medium baryons. The internal parameters of the model are determined based on nuclear phenomenology at nonstrange sector and fitted by reproducing nuclear matter properties near the saturation point. We discuss the equations of state in different nuclear environments such as symmetric nuclear matter, neutron and strange matters. We show that the results for the equations of state are in good agreement with the phenomenology of nuclear matter. We also discuss how the SU(3) baryons masses undergo changes in these various types of nuclear matter.
rate research
Read More
Exploiting certain robust topological inputs from the skyrmion description of compressed baryonic matter with a scale-chiral symmetric Lagrangian, we predict the equation of state that is consistent with the properties of nuclear matter at the equilibrium density, supports the maximum mass of massive compact star $sim 2 M_odot$ and surprisingly gives the sound velocity close to the conformal velocity $1/sqrt{3}$ at densities $gtrsim 3 n_0$. At the core of this result is the observation that parity-doubling occurs in the nucleon structure as density goes above $sim 2n_0$ with a chiral-singlet mass $m_0 sim (0.6-0.9) m_N$, hinting at a possible up-to-date unsuspected source of proton mass and an emergence at high density of scale symmetry and flavor local symmetry, both hidden in the QCD vacuum.
We report an analysis of the octet baryon masses using the covariant baryon chiral perturbation theory up to next-to-next-to-next-to-leading order with and without the virtual decuplet contributions. Particular attention is paid to the finite-volume corrections and the finite lattice spacing effects on the baryon masses. A reasonable description of all the publicly available $n_f=2+1$ lattice QCD data is achieved.Utilyzing the Feynman-Hellmann theorem, we determine the nucleon sigma terms as $sigma_{pi N}=55(1)(4)$ MeV and $sigma_{sN}=27(27)(4)$ MeV.
We report on a recent study of the ground-state octet baryon masses and sigma terms in covariant baryon chiral perturbation theory with the extended-on-mass-shell scheme up to next-to-next-to-next-to-leading order. To take into account lattice QCD artifacts, the finite-volume corrections and finite lattice spacing discretization effects are carefully examined. We performed a simultaneous fit of all the $n_f = 2+1$ lattice octet baryon masses and found that the various lattice simulations are consistent with each other. Although the finite lattice spacing discretization effects up to $mathcal{O}(a^2)$ can be safely ignored, but the finite volume corrections cannot even for configurations with $M_phi L>4$. As an application, we predicted the octet baryon sigma terms using the Feynman-Hellmann theorem. In particular, the pion- and strangeness-nucleon sigma terms are found to be $sigma_{pi N} = 55(1)(4)$ MeV and $sigma_{sN} = 27(27)(4)$ MeV, respectively.
We perform statistically rigorous uncertainty quantification (UQ) for chiral effective field theory ($chi$EFT) applied to infinite nuclear matter up to twice nuclear saturation density. The equation of state (EOS) is based on high-order many-body perturbation theory calculations with nucleon-nucleon and three-nucleon interactions up to fourth order in the $chi$EFT expansion. From these calculations our newly developed Bayesian machine-learning approach extracts the size and smoothness properties of the correlated EFT truncation error. We then propose a novel extension that uses multitask machine learning to reveal correlations between the EOS at different proton fractions. The inferred in-medium $chi$EFT breakdown scale in pure neutron matter and symmetric nuclear matter is consistent with that from free-space nucleon-nucleon scattering. These significant advances allow us to provide posterior distributions for the nuclear saturation point and propagate theoretical uncertainties to derived quantities: the pressure and incompressibility of symmetric nuclear matter, the nuclear symmetry energy, and its derivative. Our results, which are validated by statistical diagnostics, demonstrate that an understanding of truncation-error correlations between different densities and different observables is crucial for reliable UQ. The methods developed here are publicly available as annotated Jupyter notebooks.
The published theoretical data of few models (PHSD/HSD both with and without chiral symmetry restoration) applied to experimental data from collisions of nuclei from SIS to LHC energies, have been analised by using of the meta-analysis what allowed to localize a possible phase singularities of nuclear matter created in the central nucleus-nucleus collisions: The ignition of the Quark-Gluon Plasmas (QGP) drop begins already at top SIS/BEVALAC energies. This drop of QGP occupies small part, 15$%$ (an averaged radius about 5.3 fm if radius of fireball is 10 fm), of the whole volume of a fireball created at top SIS energies. The drop of exotic matter goes through a split transition (separated boundaries of sharp (1-st order) crossover and chiral symmetry restoration) between QGP and Quarkyonic matter at energy around $sqrt{s_{NN}},=,$3.5 GeV. The boundary of transition between Quarkyonic and Hadronic matter was localized between $sqrt{s_{NN}},=,$4.4 and 5.3 GeV and it is not being intersected by the phase trajectory of that drop. Critical endpoint has been localized at around $sqrt{s_{NN}},=,$9.3 GeV and a triple point - at around 12 GeV, the boundary of smooth (2-nd order) crossover transition with chiral symmetry restoration between Quarkyonic matter and QGP was localized between $sqrt{s_{NN}},=,$9.3 and 12 GeV. The phase trajectory of a hadronic corona, enveloping the drop, stays always in the hadronic phase.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
