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Title Hyperon puzzle and the RMF model with scaled hadron masses and coupling constants Author info E. E. Kolomeitsev, K. A. Maslov, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (96%) UMBFP06 - Katedra fyziky
Co-authors Maslov K. A. (2%)
Voskresensky Dmitri (2%)
Source document Journal of Physics: Conference Series. Vol. 668 (2016), pp. 1-6. - Bristol : IOP Publishing, 2016 ; SQM 2015 medzinárodná konferencia Keywords stavová rovnica relativistický model stredného poľa neutrónové hviezdy equation of state relativistic mean-field models neutron stars Language English Country Great Britian systematics 533 Annotation The equation of state of cold baryonic matter is studied within a relativistic mean-field model with hadron masses and coupling constants depending on a scalar field. We demonstrate that if the effective nucleon mass stops to decrease with a density increase at densities n > n > n0, where n0 is the nuclear saturation density, the equation of state stiffens for these densities and the limiting neutron star mass increases. The stabilization of the nucleon mass can be realised if in the equation of motion for the scalar mean-field there appear a term sharply varying in a narrow vicinity of the field value corresponding to the density n . We show several possible realizations of this mechanism getting sufficiently stiff equations of state. The appearance of hyperons in dense neutron star interiors is accounted for. The obtained equations of state remain sufficiently stiff if the reduction of the ϕ meson mass is incorporated. Thereby, the hyperon puzzle can be resolved Public work category AFC No. of Archival Copy 35029 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika 
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Title Scalar quanta in Fermi liquids: zero sounds, instabilities, Bose condensation, and a metastable state in dilute nuclear matter Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (99%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (1%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 52, no. 12 (2016), pp. [1-18]. - Berlin : Springer, 2016 Keywords heavy ion collisions equation of state relativistic mean-field models hydrodynamics Language English Country United States of America systematics 53 Annotation The spectrum of bosonic scalar-mode excitations in a normal Fermi liquid with local scalar interaction is investigated for various values and momentum dependence of the scalar Landau parameter f(0) in the particle-hole channel. For f(0) > 0 the conditions are found when the phase velocity on the spectrum of zero sound acquires a minimum at non-zero momentum. For1 < f(0) < 0 there are only damped excitations, and for f(0) <1 the spectrum becomes unstable against the growth of scalar-mode excitations. An effective Lagrangian for the scalar excitation modes is derived after performing a bosonization procedure. We demonstrate that the instability may be tamed by the formation of a static Bose condensate of the scalar modes. The condensation may occur in a homogeneous or inhomogeneous state relying on the momentum dependence of the scalar Landau parameter. We show that in the isospin-symmetric nuclear matter there may appear a metastable state at subsaturation nuclear density owing to the condensate. Then we consider a possibility of the condensation of the zero-sound-like excitations in a state with a nonzero momentum in Fermi liquids moving with overcritical velocities, provided an appropriate momentum dependence of the Landau parameter f(0)( k) > 0. We also argue that in peripheral heavy-ion collisions the Pomeranchuk instability may occur already for f(0) >1. Public work category ADC No. of Archival Copy 38091 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Making a soft relativistic mean-field equation of state stiffer at high density Author info K. A. Maslov, E. E. Kolomeitsev, D. N. Voskresensky Author Maslov K. A. (25%)
Co-authors Kolomeitsev Evgeni E. 1970- (50%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (25%)
Source document Physical Review C : Nuclear Physics. Vol. 92, no. 5 (2015), pp. [1-5]. - Maryland : American Physical Society, 2015 Keywords neutrónové hviezdy stavová rovnica relativistický model stredného poľa neutron stars equation of state relativistic mean-field models Language English Country United States of America systematics 531 Public work category ADC No. of Archival Copy 34334 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Solution of the hyperon puzzle within a relativistic mean-field model Author info K. A. Maslov, Evgeni E. Kolomeitsev, D. N. Voskresensky Author Maslov K. A. (34%)
Co-authors Kolomeitsev Evgeni E. 1970- (33%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (33%)
Source document Physics Letters B. Vol. 748 (2015), pp. 369-375. - Amsterdam : Elsevier B.V., 2015 Keywords neutrónové hviezdy neutron stars relativistic mean-field models hyperons Language English Country Netherlands Public work category ADC No. of Archival Copy 33613 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised