English
Related papers

Related papers: Bulk viscosity in superfluid neutron star cores. I…

200 papers

We study the bulk viscosity in neutron star cores due to modified Urca processes involving nucleons, electrons and muons and analize its reduction by singlet-state or triplet-state superfluidity of nucleons. In combination with the results…

Astrophysics · Physics 2009-11-06 P. Haensel , K. P. Levenfish , D. G. Yakovlev

The bulk viscosity of the neutron star matter due to the direct Urca processes involving nucleons, electrons and muons is studied taking into account possible superfluidity of nucleons in the neutron star cores. The cases of singlet-state…

Astrophysics · Physics 2009-05-13 P. Haensel , K. P. Levenfish , D. G. Yakovlev

Neutron stars are expected to contain a significant number of hyperons in addition to protons and neutrons in the highest density portions of their cores. Following the work of Jones, we calculate the coefficient of bulk viscosity due to…

Astrophysics · Physics 2009-11-07 Lee Lindblom , Benjamin J. Owen

We calculated bulk viscosity due to non-equilibrium weak processes in superfluid nucleon-hyperon matter of neutron stars. For that, the dissipative relativistic hydrodynamics, formulated in paper [1] for superfluid mixtures, was extended to…

Astrophysics · Physics 2008-11-26 M. E. Gusakov , E. M. Kantor

We discuss bulk viscosity due to non-leptonic processes involving hyperons and Bose-Einstein condensate of negatively charged kaons in neutron stars. It is noted that the hyperon bulk viscosity coefficient is a few order of magnitude larger…

Astrophysics · Physics 2008-12-31 Debarati Chatterjee , Debades Bandyopadhyay

In order to establish whether the unstable r-modes in a rotating neutron star provide a detectable source of gravitational waves, we need to understand the details of the many dissipative processes that tend to counteract the instability.…

Solar and Stellar Astrophysics · Physics 2015-05-18 Brynmor Haskell , Nils Andersson

We investigate the hyperon bulk viscosity due to the non-leptonic process $n + p \rightleftharpoons p + \Lambda $ in $K^-$ condensed matter and its effect on the r-mode instability in neutron stars. We find that the hyperon bulk viscosity…

Astrophysics · Physics 2011-02-11 Debarati Chatterjee , Debades Bandyopadhyay

The bulk viscosity due to the non-leptonic process involving hyperons in $K^-$ condensed matter is discussed here. We find that the bulk viscosity is modified in a superconducting phase. Further, we demonstrate how the exotic bulk viscosity…

Astrophysics · Physics 2009-11-13 Debarati Chatterjee , Debades Bandyopadhyay

The contribution from hyperons to the bulk viscosity of neutron star matter is calculated. Compared to previous works we use for the weak interaction the one-pion exchange model rather than a current-current interaction, and include the…

Nuclear Theory · Physics 2009-11-10 E. N. E. van Dalen , A. E. L. Dieperink

It is well-known that r-mode oscillations of rotating neutron stars may be unstable with respect to the gravitational wave emission. It is highly unlikely to observe a neutron star with the parameters within the instability window, a domain…

High Energy Astrophysical Phenomena · Physics 2019-11-22 D. D. Ofengeim , M. E. Gusakov , P. Haensel , M. Fortin

We study the bulk viscosity of neutron star matter including $\Lambda$ hyperons in the presence of quantizing magnetic fields. Relaxation time and bulk viscosity due to both the non-leptonic weak process involving $\Lambda$ hyperons and…

Astrophysics · Physics 2009-06-30 Monika Sinha , Debades Bandyopadhyay

We calculate the coefficient of bulk viscosity by considering the non-leptonic weak interactions in the cores of hybrid stars with both hyperons and quarks. We first determine the dependence of the production rate of neutrons on the…

Astrophysics · Physics 2009-11-11 Nana Pan , Xiaoping Zheng , Jiarong Li

We discuss the effects of superfluidity on the shear viscosity in a neutron star core. Our study combines existing theoretical results for the viscosity coefficients with data for the various superfluid energy gaps into a consistent…

Astrophysics · Physics 2009-11-10 N. Andersson , G. L. Comer , K. Glampedakis

We study the heat capacity and neutrino emission reactions (direct and modified Urca processes, nucleon-nucleon bremsstrahlung, Cooper pairing of nucleons) in matter of supranuclear density of the neutron star cores with superfluid neutrons…

Astrophysics · Physics 2011-02-16 D. G. Yakovlev , K. P. Levenfish , Yu. A. Shibanov

We calculate the three bulk viscosity coefficients as arising from the collisions among phonons in superfluid neutron stars. We use effective field theory techniques to extract the allowed phonon collisional processes, written as a function…

High Energy Astrophysical Phenomena · Physics 2013-07-03 Cristina Manuel , Jaume Tarrus , Laura Tolos

We investigate the effect of $K^-$ condensed matter on bulk viscosity and r-mode instability in neutron stars. The bulk viscosity coefficient due to the non-leptonic process $n \rightleftharpoons p + K^-$ is studied here. In this…

Astrophysics · Physics 2008-11-26 Debarati Chatterjee , Debades Bandyopadhyay

We investigate the effect of antikaon condensed matter on bulk viscosity in rotating neutron stars. We use relativistic field theoretical models to construct the equation of state of neutron stars with the condensate, where the phase…

Astrophysics · Physics 2007-12-31 Debarati Chatterjee , Debades Bandyopadhyay

Superfluidity of $\Lambda$ and $\Sigma^-$ admixed in neutron star (NS) cores is investigated realistically for hyperon ($Y$)-mixed NS models obtained using a $G$-matrix-based effective interaction approach. Numerical results for the…

Nuclear Theory · Physics 2009-11-11 Tatsuyuki Takatsuka , Shigeru Nishizaki , Yasuo Yamamoto , Ryozo Tamagaki

We investigate the effect of hyperon matter including hyperon-hyperon interaction on bulk viscosity. Equations of state are constructed within the framework of a relativistic field theoretical model where baryon-baryon interaction is…

Astrophysics · Physics 2009-11-11 Debarati Chatterjee , Debades Bandyopadhyay

We consider a rotating neutron star with the presence of hyperons in its core, using an equation of state in an effective chiral model within the relativistic mean field approximation. We calculate the hyperonic bulk viscosity coefficient…

High Energy Physics - Phenomenology · Physics 2014-11-20 T. K. Jha , H. Mishra , V. Sreekanth
‹ Prev 1 2 3 10 Next ›