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Title Relativistic mean-field models with scaled hadron masses and couplings Subtitle hyperons and maximum neutron star mass Author info K. A. Maslov, E. E. Kolomeitsev, D. N. Voskresensky Author Maslov K. A. (1%)
Co-authors Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (1%)
Source document Nuclear Physics A. Vol. 950 (2016), pp. 64-109. - Amsterdam : Elsevier B.V., 2016 Keywords stavová rovnica equation of state neutrónové hviezdy neutron stars fyzika - physics Language English Country Netherlands systematics 53 Public work category ADC No. of Archival Copy 36997 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika 
unrecognised
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 unrecognised
Title Viscosity of neutron star matter and r-modes in rotating pulsars Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (80%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (20%)
Source document Physical Review C : Nuclear Physics. Vol. 91, no. 2 (2015), pp. [1-35]. - Maryland : American Physical Society, 2015 Keywords neutrónové hviezdy neutron stars r-modes shear viscosity bulk viscosity superconductivity superfluidity Language English Country United States of America systematics 539.1 Annotation We study viscosity of the neutron star matter and $r$-mode instability in rotating neutron stars. Contributions to the shear and bulk viscosities from various processes are calculated accounting for in-medium modifications of the nucleon-nucleon interaction. A softening of the pion mode at densities larger than the nuclear saturation density $n_0$ and a possibility of the pion condensation at densities above $3/,n_0$ are included. The neutron-neutron and proton-proton pairings are incorporated, where necessary. In the shear viscosity we include the lepton contribution calculated taking into account the Landau damping in the photon exchange, the nucleon contribution described by the medium-modified one pion exchange, and some other terms, such as the novel phonon contribution in the 1S$_0$ superfluid neutron phase, and the neutrino term in the neutrino opacity region. The nucleon shear viscosity depends on the density rather moderately and proves to be much less than the lepton term. On the contrary, among the terms contributing to the bulk viscosity, induced by the delay of the relaxation of lepton concentrations in the star matter perturbed by the $r$-modes, the term from the two-nucleon medium modified Urca reactions possesses strongest density dependence (rising by several orders of magnitude for massive stars) because of the pion softening. Also, contributions to the bulk viscosity arising from other reactions induced by charged weak currents, e.g., in the Urca processes on a pion condensate and in direct Urca processes, are included. The radiative bulk viscosity induced by charged and neutral weak currents in the region of the neutrino transparency of the star is also calculated accounting for in-medium effects. We exploit the equation of state, which is similar to the Akmal-Pandharipande-Ravenhall equation of state up to $4/,n_0$, but is stiffer at higher densities, producing the maximum neutron star mass compatible with observations. The direct Urca processes do not appear up to $5/,n_0$ (corresponding to the star mass $M/simeq 1.9 M_{/odot}$). Computed with account of in-medium effects, the frequency boundary of the $r$-mode stability for the stars with the mass $/gsim 1.8 M_{/odot}$ proves to be above the frequencies of all rotating young pulsars. However, none of the conventional contributions to the viscosity are able to explain the stability of rapid rotation of old recycled pulsars in X-ray binaries. To solve this problem we propose a novel efficient mechanism associated with the appearance of condensates of low-lying modes of bosonic excitations with finite momentum and/or with an enhancement of the inhomogeneous pion/kaon condensates in some parts of the star, if the angular velocity exceeds a critical value Public work category ADC No. of Archival Copy 32975 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
Title Neutron stars Subtitle equation of state and structure Document part 1 Author info P. Haensel ... [et al.] Author Haensel P.
Issue data Berlin : Springer , 2007. - xxiii; 619 s. : ilustr., 24 cm Issue [1st ed.] Edition Astrophysics and space science library , 326 ISBN 978-0-387-33543-8, 0-387-33543-9 Note Bibliografia s. 543-595. Register Keywords astrofyzika - astrophysics neutrónové hviezdy vesmír - universe neutron stars priestor - space Language English Country Germany systematics 52 524.3 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xkni - BOOKS Copy count 1, currently available 0, at library only 1 
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Call number Location Sublocation Umiestnenie Info 341777 Univerzita Mateja Bela Department of physics In-Library Use Only