We calculate the kaonic contribution to the shear viscosity of quark matter in the kaon-condensed color-flavor locked phase (CFL-K0). This contribution comes from a light pseudo-Goldstone boson which arises from the spontaneous breaking of the flavor symmetry by the kaon condensate. The other contribution, from the exactly massless superfluid 'phonon", has been calculated previously. We specialize to a particular form of the interaction lagrangian, parameterized by a single coupling. We find that if we make reasonable guesses for the values of the parameters of the effective theory, the kaons have a much smaller shear viscosity than the superfluid phonons, but also a much shorter mean free path, so they could easily provide the dominant contribution to the shear viscosity of CFL-K0 quark matter in a neutron star in the temperature range 0.01 to 1 MeV (10^8 to 10^10 K).
Coexistence of kaon condensation and hyperons, which may be realized in neutron stars, is investigated on the basis of the relativistic mean-field theory combined with the effective chiral Lagrangian. It is shown that kaon-condensed phase in hyperon-mixed matter is plausible, but it leads to significant softening of the equation of state (EOS).We discuss indispensable effects which make the EOS stiffer so as to be consistent with recent neutron-star observations.
The recent measurement of the mass of neutron stars (PSR J1614 - 2230, PSR J0348 + 0432, MSP J0740 + 6620) restricts the lower limit $\sim 2M_{\odot}$ of the maximum mass of such compact stars, making it possible for dense matter to exist in massive stars. The relativistic mean field theory with parameter sets FSUGold including Kaon condensation is used to describe the properties of neutron stars in $β$ equilibrium. Through careful choice of the parameter of the $σ$-cut $c_σ$, we are able to produce a maximum mass neutron star with Kaon condensation heavier than $2M_{\odot}$, and we find that …
Functional renormalisation group approach is applied to a system of kaons with finite chemical potential. A set of approximate flow equations for the effective couplings is derived and solved. At high scale the system is found to be at the normal phase whereas at some critical value of the running scale it undergoes the phase transition (PT) to the phase with a spontaneously broken symmetry with the kaon condensate as an order parameter. The value of the condensate turns out to be quite sensitive to the kaon-kaon scattering length.
本文结合了作者的两次演讲，并基于与GE合作完成的工作。布朗和D.-用手征微扰理论处理重子介质中的K介子凝聚。除最近发表的文献外，还包括Brown和Bethe讨论的K介子凝聚的天体物理背景，以及与H. K.李和S.- J. Sin和K. M. Westerberg在Skyrme模型的束缚态方法中。预计带负电荷的K介子会在一个临界密度$2\lsim ρ/ρ_0\lsim 4$下凝聚，这个临界密度的范围允许布朗和贝特预测的有趣的新现象在致密的恒星物质中发生。
We investigate nuclear matter equations of state in neutron star with kaon condensation. It is generally known that the existence of kaons in neutron star makes the equation of state soft so that the maximum mass of neutron star is not likely to be greater than 2.0 $M_{\odot}$, the maximum mass constrained by current observations. With existing Skyrme force model parameters, we calculate nuclear equations of state and check the possibility of kaon condensation in the core of neutron stars. The results show that even with the kaon condensation, the nuclear equation of state satisfies both the m…
Possibility of kaon-condensed phase in hyperon-mixed matter is considered on the basis of chiral symmetry for kaon-baryon and kaon-kaon interactions, being combined with the relativistic mean-field theory for two-body baryon interaction. In addition, universal three-baryon repulsive force in the string-junction model and phenomenological three-nucleon attractive force are introduced. It is shown that softening of the equation of state stemming from both kaon condensation and mixing of hyperons is compensated with the repulsive effect of the three-baryon force and the relativistic effect for tw…
Possible coexistence of kaon condensation and hyperons in highly dense matter [the ($Y+K$) phase] is investigated on the basis of the relativistic mean-field theory combined with the effective chiral Lagrangian. Two coupling schemes for the $s$-wave kaon-baryon interaction are compared regarding the onset density of kaon condensation in the hyperon-mixed matter and equation of state for the developed ($Y+K$) phase: One is the contact interaction scheme related to the nonlinear effective chiral Lagrangian. The other is the meson-exchange scheme, where the interaction vertices between the kaon f…
It is argued that a well measured double neutron star binary in which the two neutron stars are more than 4% different from each other in mass or a massive neutron star with mass M > 2 M_sun would put in serious doubt or simply falsify the following chain of predictions: (1) nearly vanishing vector meson mass at chiral restoration, (2) kaon condensation at a density n ~ 3 n_0, (3) the Brown-Bethe maximum neutron star mass M_max ~ 1.5 M_sun and (4) Smolin's `Cosmological Natural Selection' hypothesis.
S-wave kaon condensation in neutron-star matter within a chiral model framework with dynamical meson masses
Center for Nuclear Research, Department of Physics, Kent State University（肯特州立大学核研究中心物理系）；Department of Physics, Kent State University（肯特州立大学物理系）；Department of Physics, MRPD Government College Talwara（塔尔瓦拉MRPD政府学院物理系）；Department of Physics, University of Houston（休斯顿大学物理系）；Department of Physics, Catholic Institute of Technology（天主教理工学院物理系）；Universidade Federal Fluminense（弗鲁米嫩塞联邦大学）；ICRANet（国际相对论天体物理中心网络）
Recent observations of several massive pulsars, with masses near and above $2~M_\odot$, point towards the existence of matter at very high densities, compared to normal matter that we are familiar with in our terrestrial world. This leads to the possibility of appearance of exotic degrees of freedom other than nucleons inside the core of the neutrons stars (NS). Another significant property of NSs is the presence of high surface magnetic field, with highest range of the order of $\sim~10^{16}$ G. We study the properties of highly dense matter with the possibility of appearance of heavier stran…
