Gyorgy Wolf

@wigner.hu

Theoretical Department
Wigner RCP



                 

https://researchid.co/wolfgyuri

RESEARCH, TEACHING, or OTHER INTERESTS

Nuclear and High Energy Physics, Astronomy and Astrophysics

105

Scopus Publications

4605

Scholar Citations

32

Scholar h-index

54

Scholar i10-index

Scopus Publications

  • Sensitivity of finite size effects to the boundary conditions and the vacuum term
    Győző Kovács, Péter Kovács, György Wolf, Pok Man Lo, and Krzysztof Redlich
    American Physical Society (APS)
    Finite volume effects are studied both with low-momentum cutoff and with momentum discretization in the framework of an (axial)vector meson extended quark-meson model with Polyakov-loop variables. In the momentum cutoff scenario, the CEP moves to lower temperatures and larger quark chemical potentials as the characteristic system size is reduced, however, the treatment of the vacuum term significantly affects its trajectory. The size dependence of the baryon fluctuations is also studied by the kurtosis and the skewness, both of which show moderate dependence on temperature and some dependence on quark chemical potential. The order of the phase transition is also studied near the chiral limit at finite system size and found to be second-order only at vanishing explicit breaking. The implementation of the finite size effect with momentum discretization is more complicated and shows peculiar behavior due to the different modes dropping below the Fermi surface and strong dependence on the type of the boundary condition chosen. We found that both the different boundary conditions and the treatment of the vacuum term cause significant changes in the trajectory of the CEP as the characteristic system size is changed.

  • What neutron stars tell about the hadron-quark phase transition: A Bayesian study
    János Takátsy, Péter Kovács, György Wolf, and Jürgen Schaffner-Bielich
    American Physical Society (APS)
    The existence of quark matter inside the heaviest neutron stars has been the topic of numerous recent studies, many of them suggesting that a phase transition to strongly interacting conformal matter inside neutron stars is feasible. Here we examine this hybrid star scenario using a soft and a stiff hadronic model, a constituent quark model with three quark flavours, and applying a smooth crossover transition between the two. Within a Bayesian framework, we study the effect of up-to-date constraints from neutron star observations on the equation-of-state parameters and various neutron star observables. Our results show that a pure quark core is only possible if the maximum mass of neutron stars is below $\\sim2.35~M_\\odot$. However, we also find, consistently with other studies, that a peak in the speed of sound, exceeding $1/3$, is highly favoured by astrophysical measurements, which might indicate the percolation of hadrons at $\\sim3-4n_0$. Even though our prediction for the phase transition parameters varies depending on the specific astrophysical constraints utilized, the position of the speed of sound peak only changes slightly, while the existence of pure quark matter below $\\sim4 n_0$, using our parameterization, is disfavoured. On the other hand, the preferred range for the EoS shows signs of conformality above $\\sim4n_0$. Additionally, we present the difference in the upper bounds of radius estimates using the full probability density data and sharp cut-offs, and stress the necessity of using the former.

  • Synthesis of Elements in Compact Stars in Pycnonuclear Reactions with Carbon Isotopes: Quasibound States vs. States of Zero-Points Vibrations
    Sergei P. Maydanyuk, Gyorgy Wolf, and Kostiantyn A. Shaulsky
    MDPI AG
    (1) Purpose: Conditions of formation of compound nuclear systems needed for synthesis of heavy nuclei in pycnonuclear reactions in compact stars are studied on a quantum mechanical basis. (2) Methods: The method of multiple internal reflections is applied for pycnonuclear reactions in compact stars with new calculations of quasibound spectra and spectra of zero-point vibrations. (3) Results: Peculiarities of the method are analyzed for reaction with isotopes of Carbon. The developed method takes into account continuity and conservation of quantum flux (describing pycnonuclear reaction) inside the full spacial region of reaction, including the nuclear region. This gives the appearance of new states (called quasibound states) in which compound nuclear systems of Magnesium are formed with the largest probability. These states have not been studied yet in synthesis of elements in stars. Energy spectra of zero-point vibrations and spectra of quasibound states are estimated with high precision for reactions with isotopes of Carbon. For the first time, the influence of plasma screening on quasibound states and states of zero-point vibrations in pycnonuclear reactions has been studied. (4) Conclusions: The probability of formation of a compound nucleus in quasibound states in pycnonuclear reaction is essentially larger than the probability of formation of this system in states of zero-point vibrations studied by Zel’dovich and followers. Therefore, synthesis of Magnesium from isotopes of Carbon is more probable through the quasibound states than through the states of zero-point vibrations in compact stars. Energy spectra of zero-point vibrations are changed essentially after taking plasma screening into account. Analysis shows that from all studied isotopes of Magnesium, only 24Mg is stable after synthesis at an energy of relative motion of 4.881 MeV of the incident nuclei 12C.

  • Neutron star properties in the (axial)vector meson extended linear sigma model
    János Takátsy, Péter Kovács, György Wolf, and Jürgen Schaffner‐Bielich
    Wiley
    AbstractThe equation of state provided by effective models of strongly interacting matter should comply with the restrictions imposed by current astrophysical observations on compact stars. We explore the possibility, that there is quark matter in the center of neutron stars. For the equation of state of the neutron star matter, we use a relativistic mean field model for the hadronic one and the (axial‐)vector meson extended linear sigma model for the quark phase. We assume that the transition is a cross‐over between these phases. We connect the two branches in this cross‐over regime continuously by a polynomial. This equation of state should comply with the restrictions imposed by current astrophysical observations on compact stars. Our model has four free parameters that should be fitted to experimental data. By using a Bayesian analysis, we found that our model could explain all the experimental constraints; furthermore, we have obtained the most probable parameter set for our model.

  • Finite volume effects in the extended linear sigma model via low momentum cutoff


  • Hypernuclei production with a modified coalescence model in BUU transport calculations
    Gábor Balassa and György Wolf
    Springer Science and Business Media LLC
    AbstractIn this paper, the usual momentum- and coordinate-space distance criteria for creating nuclear clusters in transport simulations are readdressed by using a dynamical, covariant description in an off-shell Boltzmann-Uehling-Uhlenbeck transport approach. The free parameter of this clustering scheme is the cluster formation time, which is fitted through the FOPI data of low energy charged cluster multiplicities in Au+Au collisions at 150 A MeV, and 400 A MeV incident energies. The coalescence model is used to estimate the yields of the $$^3$$ 3 H$$_\\Lambda $$ Λ , $$^5$$ 5 H$$_{\\Lambda \\Lambda }$$ Λ Λ , $$^6$$ 6 He$$_{\\Lambda \\Lambda }$$ Λ Λ single and double strange hypernuclei in central Au+Au collisions between 2, and 20 A GeV incident energies, giving comparable results to estimations from other methods.

  • Neutron star properties with careful parametrization in the vector and axial-vector meson extended linear sigma model
    Péter Kovács, János Takátsy, Jürgen Schaffner-Bielich, and György Wolf
    American Physical Society (APS)
    The existence of quark matter inside the cores of heavy neutron stars is a possibility which can be probed with modern astrophysical observations. We use an (axial)vector meson extended quarkmeson model to describe quark matter in the core of neutron stars. We discover that an additional parameter constraint is necessary in the quark model to ensure chiral restoration at high densities. By investigating hybrid star sequences with various parameter sets we show that low sigma meson masses are needed to fulfill the upper radius constraints, and that the maximum mass of stable hybrid stars is only slightly dependent on the parameters of the crossover-type phase transition. Using this observation and results from recent astrophysical measurements a constraint of 2.6 < gV < 4.3 is set for the constituent quark – vector meson coupling. The effect of a nonzero bag constant is also investigated and we observe that its effect is small for values adopted in previous works.

  • Production cross sections of tetraquark states in elementary hadronic collisions
    Gábor Balassa and György Wolf
    Springer Science and Business Media LLC
    AbstractInclusive production cross sections of the possible exotic state X(3872) in proton–proton, pion-proton and proton–antiproton collisions are calculated using a statistical based model, which is previously used to describe inclusive charmed and bottomed hadron production cross sections in the low energy region. With the extensions made here the model is capable to include tetraquarks as well, using the diquark picture of tetraquarks. The evaluated cross section ratio of $$\\varPsi (2S)$$ Ψ ( 2 S ) and X(3872) at $$\\sqrt{s}=7$$ s = 7 TeV agrees well with the measured value.

  • Observation of charmonium mass modification in antiproton induced reactions
    GYORGY WOLF, GABOR BALASSA, and SU HOUNG LEE
    WORLD SCIENTIFIC

  • Hybrid star properties from an extended linear sigma model
    János Takátsy, Péter Kovács, and György Wolf
    Wiley
    AbstractThe equation of state provided by effective models of strongly interacting matter should comply with the restrictions imposed by current astrophysical observations on compact stars. Using the equation of state given by the (axial‐)vector meson extended linear sigma model, we determine the mass–radius relation and study whether these restrictions are satisfied under the assumption that most of the star is filled with quark matter. We study the dependence of the mass–radius relation on the parameters of the model.

  • CBM Collaboration
    T. Ablyazimov, R.P. Adak, A. Adler, A. Agarwal, K. Agarwal, Z. Ahammed, A. Ahmad, F. Ahmad, N. Ahmad, A. Akindinov,et al.
    Elsevier BV

  • Charmed and bottomed hadronic cross sections from a statistical model
    Gábor Balassa and György Wolf
    Springer Science and Business Media LLC
    AbstractIn this work, we extended our statistical model with charmed and bottomed hadrons, and fit the quark creational probabilities for the heavy quarks, using low energy inclusive charmonium and bottomonium data. With the finalized fit for all the relevant types of quarks (up, down, strange, charm, bottom) at the energy range from a few GeV up to a few tens of GeV’s, the model is now considered complete. Some examples are also given for proton–proton, pion–proton, and proton–antiproton collisions with charmonium, bottomonium, and open charm hadrons in the final state.

  • A statistical model to calculate inclusive hadronic cross sections
    Gábor Balassa and György Wolf
    Springer Science and Business Media LLC
    AbstractHadronic cross sections are important ingredients in many of the ongoing research methods in high energy nuclear physics, and it is always important to measure and/or calculate the probabilities of different types of reactions. In heavy-ion transport simulations at a few GeV energies, these hadronic cross sections are essential and so far mostly the exclusive processes are used, however, if one interested in total production rates the inclusive cross sections are also necessary to know. In this paper, we introduce a statistical-based method, which is able to give good estimates to exclusive and inclusive cross sections as well in the energy range of a few GeV. The method and its estimates for not well-known cross sections, will be used in a Boltzmann-Uehling-Uhlenbeck (BUU) type off-shell transport code to explain charmonium and bottomonium mass shifts in heavy-ion collisions.

  • Compact star properties from an extended linear sigma model
    János Takátsy, Péter Kovács, Zsolt Szép, and György Wolf
    MDPI AG
    The equation of state provided by effective models of strongly interacting matter should comply with the restrictions imposed by current astrophysical observations of compact stars. Using the equation of state given by the (axial-)vector meson extended linear sigma model, we determine the mass–radius relation and study whether these restrictions are satisfied under the assumption that most of the star is filled with quark matter. We also compare the mass–radius sequence with those given by the equations of state of somewhat simpler models.


  • Singularities in Einstein–conformally coupled Higgs cosmological models
    László B. Szabados and György Wolf
    Springer Science and Business Media LLC

  • Mass shift of charmonium states in p¯A collision
    György Wolf, Gábor Balassa, Péter Kovács, Miklós Zétényi, and Su Houng Lee
    Elsevier BV

  • Subthreshold Ξ<sup>-</sup> Production in proton-nucleus collisions in a BUU model
    Miklós Zétényi and György Wolf
    EDP Sciences
    We study the production of the doubly strange Ξ baryon in subthreshold p + A collisions using a BUU type transport model. We propose a new mechanism for Ξ creation in a two-step process via hyperon-nucleon collisions. We study the influence of the anisotropy of hyperon production in N + N collisions on the Ξ multiplicity. Applying reasonable assumptions on the unknown elementary cross sections, we are able to reconstruct the Ξ yield observed by the HADES collaboration (GSI, Darmstadt) in subthreshold p+Nb collisions.

  • A statistical method to estimate low-energy hadronic cross sections
    Gábor Balassa, Péter Kovács, and György Wolf
    Springer Science and Business Media LLC

  • Charmonium excitation functions in pA collisions
    Gy. Wolf, G. Balassa, P. Kovács, M. Zétényi, and S.H. Lee
    Jagiellonian University
    We study the excitation function of the low-lying charmonium state: $\\Psi$(3686) in $\\bar p$ Au collisions taking into account their in-medium propagation. The time evolution of the spectral functions of the charmonium state is studied with a BUU type transport model. We calculated the excitation function of $\\Psi$(3686) production and show that it is strongly effected by the medium. The energy regime will be available for the PANDA experiment.

  • Challenges in QCD matter physics --The scientific programme of the Compressed Baryonic Matter experiment at FAIR
    T. Ablyazimov, A. Abuhoza, R. P. Adak, M. Adamczyk, K. Agarwal, M. M. Aggarwal, Z. Ahammed, F. Ahmad, N. Ahmad, S. Ahmad,et al.
    Springer Science and Business Media LLC

  • Charmonium spectral functions in pA collision
    Gy. Wolf, G. Balassa, P. Kovács, M. Zétényi, and S.H. Lee
    Jagiellonian University
    We study the in-medium propagation of low-lying charmonium states: $J/\\Psi$, $\\Psi$(3686), and $\\Psi$(3770) in a $\\bar p$ Au $10$ GeV collision. This energy regime will be available for the PANDA experiment. The time evolution of the spectral functions of the charmonium states is studied with a BUU type transport model. We observe a substantial effect of the medium in the dilepton spectrum.

  • Phase diagram and isentropic curves from the vector meson extended polyakov quark meson model
    P. Kovács and Gy. Wolf
    Jagiellonian University
    In the framework of the $N_f = 2+1$ flavor (axial)vector meson extended Polyakov quark meson model we investigate the QCD phase diagram at finite temperature and density. We use a $\\chi^2$ minimization procedure to parameterize the model based on tree\\,-\\,level decay widths and vacuum scalar and pseudoscalar curvature masses which incorporate the contribution of the constituent quarks. Using a hybrid approximation (mesons at tree level, fermions at one\\,-\\,loop level) for the grand potential we determine the phase boundary both on the $\\mu_B-T$ and $\\rho-T$ planes. We also determine the location of the critical end point of the phase diagram. Moreover by calculating the pressure and other thermodynamical quantities derived from it, we determine a set of isentropic curves in the crossover region. We show that the curves behave very similarly as their counterparts obtained from the lattice in the crossover regime.

  • The phase diagram in the vector meson extended linear sigma model
    Gy. Wolf and P. Kovács
    Jagiellonian University
    We investigate the chiral phase transition of the strongly interacting matter at nonzero temperature and baryon chemical potential $\\mu_B$ within an extended (2+1) flavor Polyakov constituent quark-meson model which incorporates the effect of the vector and axial vector mesons. The parameters of the model are determined by comparing masses and tree-level decay widths with experimental values. We examine the restoration of the chiral symmetry by monitoring the temperature evolution of condensates. We study the $T-\\rho_B$ phase diagram of the model and find that a critical end point exists, although at very low density.

  • Dilepton and φ meson production in elementary and nuclear collisions at the NICA fixed-target experiment
    György Wolf and Miklós Zétényi
    Springer Science and Business Media LLC

RECENT SCHOLAR PUBLICATIONS

  • Structure of nuclei in dileptons production in proton-nucleus scattering
    SP Maydanyuk, G Wolf
    arXiv preprint arXiv:2410.14162 2024

  • Incoherent processes in dileptons production in proton-nucleus scattering at high energies
    SP Maydanyuk, G Wolf
    arXiv preprint arXiv:2312.07372 2023

  • Synthesis of Elements in Compact Stars in Pycnonuclear Reactions with Carbon Isotopes: Quasibound States vs. States of Zero-Points Vibrations
    SP Maydanyuk, G Wolf, KA Shaulsky
    Universe 9 (8), 354 2023

  • Observation of charmonium mass modification in antiproton induced reactions
    G Wolf, G Balassa, SH Lee
    GRIBOV-90 MEMORIAL VOLUME: FIELD THEORY, SYMMETRY, AND RELATED TOPICS 2021

  • CBM Collaboration
    T Ablyazimov, RP Adak, A Adler, A Agarwal, K Agarwal, Z Ahammed, ...
    Nuclear Physics A 1005, 122089 2021

  • A statistical model to calculate inclusive hadronic cross sections
    G Balassa, G Wolf
    The European Physical Journal A 56 (6), 174 2020

  • Charmonium Excitation functions in A Collisions
    G Wolf, G Balassa, P Kovcs, M Ztnyi, SH Lee
    arXiv preprint arXiv:1901.09910 2019

  • Observation of charmonium mass modification in proton induced reactions
    G Wolf, G Balassa, P Kovacs, M Zetenyi, SH Lee
    Proceedings of the 8th International Conference on Quarks and Nuclear 2019

  • The phase diagram in the vector meson extended linear sigma model
    G Wolf, P Kovcs
    arXiv preprint arXiv:1711.10879 2017

  • Charmonium spectral functions in collision
    G Wolf, G Balassa, P Kovcs, M Ztnyi, SH Lee
    arXiv preprint arXiv:1711.10372 2017

  • Challenges in QCD matter physics--The scientific programme of the Compressed Baryonic Matter experiment at FAIR
    T Ablyazimov, A Abuhoza, RP Adak, M Adamczyk, K Agarwal, ...
    The European Physical Journal A 53, 1-14 2017

  • Existence of the critical endpoint in the vector meson extended linear sigma model
    P Kovcs, Z Szp, G Wolf
    Physical Review D 93 (11), 114014 2016

  • Existence of the critical endpoint in the vector meson extended linear sigma model
    G Wolf
     2016

  • Thermal, chemical and spectral equilibration in heavy-ion collisions
    GA Almsi, G Wolf
    Nuclear Physics A 943, 117-136 2015

  • Angular distributions in πN→ Ne"+ e"-
    E Speranza, B Friman, G Wolf, M Zetenyi
    Verhandlungen der Deutschen Physikalischen Gesellschaft 2015

  • Chiral phase transition in an extended linear sigma model: initial results
    G Wolf, P Kovcs, Z Szp
    arXiv preprint arXiv:1411.5539 2014

  • Zero temperature properties of mesons and baryons from an extended linear sigma-model
    P Kovacs, G Wolf
    Journal of Physics: Conference Series 503 (1), 012035 2014

  • Baryon octet and decuplet phenomenology in a three-flavor extended linear sigma model
    P Kovcs, Lukcs, J Vrczy, G Wolf, M Ztnyi
    Physical Review D 89 (5), 054004 2014

  • Baryon and meson phenomenology in the extended Linear Sigma Model
    F Giacosa, A Habersetzer, K Teilab, W Eshraim, F Divotgey, L Olbrich, ...
    Verhandlungen der Deutschen Physikalischen Gesellschaft 2014

  • Effects of (axial) vector mesons on the chiral phase transition: initial results
    P Kovcs, Z Szp, G Wolf
    EPJ Web of Conferences 81, 05017 2014

MOST CITED SCHOLAR PUBLICATIONS

  • Challenges in QCD matter physics--The scientific programme of the Compressed Baryonic Matter experiment at FAIR
    T Ablyazimov, A Abuhoza, RP Adak, M Adamczyk, K Agarwal, ...
    The European Physical Journal A 53, 1-14 2017
    Citations: 413

  • Direct Measurements of Charmed--Meson Hadronic Branching Fractions
    RM Baltrusaitis, JJ Becker, GT Blaylock, JS Brown, KO Bunnell, ...
    Physical review letters 56 (20), 2140 1986
    Citations: 367

  • Dilepton production in heavy-ion collisions
    G Wolf, G Batko, W Cassing, U Mosel, K Niita, M Schfer
    Nuclear Physics A 517 (3-4), 615-638 1990
    Citations: 310

  • Pion-production in heavy-ion collisions at SIS energies
    S Teis, W Cassing, M Effenberger, A Hombach, U Mosel, G Wolf
    Zeitschrift fr Physik A Hadrons and Nuclei 356, 421-435 1996
    Citations: 303

  • Observation of a narrow KK state in J/ψ radiative decays
    RM Baltrusaitis, JJ Becker, GT Blaylock, T Bolton, JS Brown, KO Bunnell, ...
    Physical Review Letters 56 (2), 107 1986
    Citations: 283

  • Scattering of vector mesons off nucleons
    MFM Lutz, G Wolf, B Friman
    Nuclear Physics A 706 (3-4), 431-496 2002
    Citations: 235

  • Meson vacuum phenomenology in a three-flavor linear sigma model with (axial-) vector mesons
    D Parganlija, P Kovacs, G Wolf, F Giacosa, DH Rischke
    Physical Review D—Particles, Fields, Gravitation, and Cosmology 87 (1), 014011 2013
    Citations: 222

  • Nuc!. Phys, A517 (1990) 615; Gy. Wolf, W. Cassing and U. Mosel
    G Wolf, G Batko
    Nucl. Phys. A 552, 549 1993
    Citations: 219

  • Study of the radiative decay J/ψ→γρρ
    RM Baltrusaitis, D Coffman, J Hauser, DG Hitlin, JD Richman, JJ Russell, ...
    Physical Review D 33 (5), 1222 1986
    Citations: 126

  • Radiative decays of the J/ψ into γ and γ
    RM Baltrusaitis, D Coffman, G Dubois, G Eigen, J Hauser, DG Hitlin, ...
    Physical Review D 35 (7), 2077 1987
    Citations: 119

  • Subthreshold K+-production in proton-nucleus reactions
    W Cassing, G Batko, U Mosel, K Niita, O Schult, G Wolf
    Physics Letters B 238 (1), 25-30 1990
    Citations: 113

  • Eta and dilepton production in heavy-ion reactions
    G Wolf, W Cassing, U Mosel
    Nuclear Physics A 545 (1-2), 139-150 1992
    Citations: 109

  • Existence of the critical endpoint in the vector meson extended linear sigma model
    P Kovcs, Z Szp, G Wolf
    Physical Review D 93 (11), 114014 2016
    Citations: 102

  • Resonance properties in nuclear matter
    W Ehehalt, W Cassing, A Engel, U Mosel, G Wolf
    Physical Review C 47 (6), R2467 1993
    Citations: 95

  • Transport theories for heavy-ion collisions in the 1 A GeV regime
    EE Kolomeitsev, C Hartnack, HW Barz, M Bleicher, E Bratkovskaya, ...
    Journal of Physics G: Nuclear and Particle Physics 31 (6), S741 2005
    Citations: 91

  • Leptonic Branching Ratios and a Search for Goldstone-Boson Decay
    RM Baltrusaitis, JJ Becker, GT Blaylock, JS Brown, KO Bunnell, ...
    Physical review letters 55 (18), 1842 1985
    Citations: 91

  • Antiproton production in p-nucleus and nucleus-nucleus collisions
    G Batko, W Cassing, U Mosel, K Niita, G Wolf
    Physics Letters B 256 (3-4), 331-336 1991
    Citations: 78

  • From meson-nucleon scattering to vector mesons in nuclear matter
    B Friman, M Lutz, G Wolf
    arXiv preprint nucl-th/0003012 2000
    Citations: 69

  • Effects of pion and delta selfenergies in nucleus-nucleus reactions
    W Ehehalt, W Cassing, A Engel, U Mosel, G Wolf
    Physics Letters B 298 (1-2), 31-35 1993
    Citations: 69

  • Pion-nucleus reactions in a microscopic transport model
    A Engel, W Cassing, U Mosel, M Schfer, G Wolf
    Nuclear Physics A 572 (3-4), 657-681 1994
    Citations: 62