Observables and open problems for NICA

Bratkovskaya, Elena; Cassing, W.; Moreau, P.; Palmese, A.

doi:10.1140/epja/i2016-16219-6

Cited by 2 publications

(4 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, due to a partial restoration of chiral symmetry close to the hadron-parton transition the ss production threshold is lowered in a dense hadronic medium and strangeness enhancement might also signal chiral symmetry restoration rather than deconfinement as suggested in Refs. [11][12][13][14]. We note that quark confinement and chiral symmetry breaking are not intimately connected at finite µ B [15].…”

Section: Introductionmentioning

confidence: 77%

Baryon-antibaryon annihilation and reproduction in relativistic heavy-ion collisions

Seifert

Cassing

2018

Phys. Rev. C

Self Cite

View full text Add to dashboard Cite

The quark rearrangement model for baryon-antibaryon annihilation and reproduction (BB ↔ 3M)-incorporated in the Parton-Hadron-String Dynamics (PHSD) transport approach-is extended to the strangeness sector. A derivation of the transition probabilities for the three-body processes is presented and a strangeness suppression factor for the invariant matrix element squared is introduced to account for the higher mass of the strange quark compared to the light up and down quarks. In simulations of the baryon-antibaryon annihilation and reformation in a box with periodic boundary conditions, we demonstrate that our numerical implementation fulfills detailed balance on a channel-by-channel basis for more than 2000 individual 2 ↔ 3 channels. Furthermore, we study central Pb+Pb collisions within PHSD from 11.7A GeV to 158A GeV and investigate the impact of the additionally implemented reaction channels in the strangeness sector. We find that the new reaction channels have a visible impact essentially only on the rapidity spectra of antibaryons. The spectra with the additional channels in the strangeness sector are closer to the experimental data than without for all antihyperons. Due to the chemical redistribution between baryons-antibaryons and mesons we find a slightly larger production of antiprotons thus moderately overestimating the available experimental data. We additionally address the question if the antibaryon spectra (with strangeness) from central heavy-ion reactions at these energies provide further information on the issue of chiral symmetry restoration and deconfinement. However, by comparing transport results with and without partonic phase as well as including and excluding effects from chiral symmetry restoration we find no convincing signals in the strange antibaryon sector for either transition due to the strong final-state interactions.

show abstract

Section: Introductionmentioning

confidence: 77%

Baryon-antibaryon annihilation and reproduction in relativistic heavy-ion collisions

Seifert

Cassing

2018

Phys. Rev. C

Self Cite

View full text Add to dashboard Cite

show abstract

“…More recently, it has been also shown to provide a microscopic description of the maximum in the K + /π + ratio in central nucleus-nucleus collisions [9][10][11].…”

Section: Reminder Of the Phsd Transport Approachmentioning

confidence: 99%

“…On the other hand there was no conclusive interpretation of the "horn" from dynamical approaches for HIC, like microscopic transport models [7,8]. Only recently, the Parton-Hadron-String Dynamics (PHSD), a transport approach describing HIC on the basis of partonic, hadronic and string degrees-of-freedom, obtained a striking improvement on this issue when including chiral symmetry restoration (CSR) in the string decay for hadronic particle production [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Signatures of chiral symmetry restoration and its survival throughout the hadronic phase interactions

et al. 2018

Self Cite

View full text Add to dashboard Cite

Abstract. The effect of the chiral symmetry restoration (CSR) on observables from heavy-ion collisions is studied in the energy range √ s NN =3-20 GeV within the PartonHadron-String Dynamics (PHSD) transport approach. The PHSD includes the deconfinement phase transition as well as essential aspects of CSR in the dense and hot hadronic medium, which are incorporated in the Schwinger mechanism for the hadronic particle production. We adopt different parametrizations of the nuclear equation of state from the non-linear σ − ω model, which enter in the computation of the quark scalar density for the CSR mechanism, in order to estimate the uncertainty in our calculations. For the pion-nucleon Σ-term we adopt Σ π ≈ 45 MeV which corresponds to a 'world average'. Our systematic studies show that chiral symmetry restoration plays a crucial role in the description of heavy-ion collisions at √ s NN =3-20 GeV, realizing an increase of the hadronic particle production in the strangeness sector with respect to the non-strange one. We identify particle abundances and rapidity spectra to be suitable probes in order to extract information about CSR, while transverse mass spectra are less sensitive ones. Our results provide a microscopic explanation for the "horn" structure in the excitation function of the K + /π + ratio: the CSR in the hadronic phase produces the steep increase of this particle ratio up to √ s NN ≈ 7 GeV, while the drop at higher energies is associated to the appearance of a deconfined partonic medium.

show abstract

Observables and open problems for NICA

Cited by 2 publications

References 67 publications

Baryon-antibaryon annihilation and reproduction in relativistic heavy-ion collisions

Baryon-antibaryon annihilation and reproduction in relativistic heavy-ion collisions

Signatures of chiral symmetry restoration and its survival throughout the hadronic phase interactions

Contact Info

Product

Resources

About