Seismology of adolescent neutron stars: Accounting for thermal effects and crust elasticity

Krüger, C.; Ho, Wynn C. G.; Andersson, Nils

doi:10.1103/physrevd.92.063009

Cited by 63 publications

(69 citation statements)

References 90 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We also note that the quadrupolar oscillations of neutron stars taking into account the elasticity of the neutron star crust have been studied by Finn [36] and Krüger et al [38]. We have checked that our final set of perturbation equations for crystalline matter agrees with their relevant equations in the zero-frequency limit.…”

mentioning

confidence: 61%

See 1 more Smart Citation

Tidal deformations of compact stars with crystalline quark matter

2017

View full text Add to dashboard Cite

We study the tidal deformability of bare quark stars and hybrid compact stars composed of a quark matter core in general relativity, assuming that the deconfined quark matter exists in a crystalline color superconducting phase. We find that taking the elastic property of crystalline quark matter into account in the calculation of the tidal deformability can break the universal I-Love relation discovered for fluid compact stars, which connects the moment of inertia and tidal deformability. Our result suggests that measurements of the moment of inertia and tidal deformability can in principle be used to test the existence of solid quark stars, despite our ignorance of the high density equation of state (EOS). Assuming that the moment of inertia can be measured to 10% level, one can then distinguish a 1.4 (1) M⊙ solid quark star described by our quark matter EOS model with a gap parameter ∆ = 25 MeV from a fluid compact star if the tidal deformability can be measured to about 10% (45%) level. On the other hand, we find that the nuclear matter fluid envelope of a hybrid star can screen out the effect of the solid core significantly so that the resulting I-Love relation for hybrid stars still agrees with the universal relation for fluid stars to about 1% level.PACS numbers: 04.30. Db, 25.75.Nq, 97.60.Jd Introduction. The possibility that deconfined quark matter may exist in the ultra-high density cores of compact stars has been of great interest since it was first proposed a few decades ago [1-3]. Our current understanding of the QCD phase diagram also suggests that deconfined quarks at the low-temperature and high-density regime can form a condensate of Cooper pairs driven by the BCS mechanism due to the existence of attractive channels of quark-quark interactions and become color superconducting [4][5][6][7] (see [8] for a review). Soon after their births in supernova explosions, the temperature of compact stars drops quickly below 10 11 K (equivalent to about 10 MeV), the typical transition temperature expected for color superconductivity, and hence it is believed that deconfined quark matter (if exists) inside compact stars can be in a color-superconducting phase.At the core of compact stars, it may be energetically favorable for quark matter to form an inhomogeneous condensate resulting in a crystalline color-superconducting (CCS) phase [9-13] (see [14] for a recent review). If our current understanding of QCD in the high-density (but still nonperturbative) regime is correct, it is then possible that hybrid stars featuring a nuclear-matter envelope on top of a CCS quark matter core can exist [15]. On the other hand, bare solid quark stars composed of CCS quark matter could also be possible if deconfined quark matter is the true ground state of matter [16].One of the special properties of the CCS quark matter is that it is extremely rigid. The shear modulus of this crystalline phase can be at least a factor of 20 to 1000 larger than that in traditional neutron star crusts

show abstract

mentioning

confidence: 61%

“…As the background star is assumed to be in an unstrained state, T shear αβ in fact contributes only at the perturbation level through [36][37][38] δT…”

mentioning

confidence: 99%

Tidal deformations of compact stars with crystalline quark matter

2017

View full text Add to dashboard Cite

show abstract

“…In the bulk of the literature on crustal dynamics, it is naively assumed that the relevant region of the star is the entire region for which ρ < ρcc. However, the outer crust (ρ < ρ nd ) only crystallises for temperatures below around 10 9 K (Haensel & Pichon 1994;Krüger et al 2015) and so all or part of this region will be liquid for young neutron stars, or for those with an internal heating mechanism like magnetars (Kaminker et al 2009). Furthermore, even if parts of the outer crust are formally just cold enough to solidify, the crystalline lattice would presumably be so weak that it would not be able to harbour any significant stress.…”

Section: Materials Properties Of the Crustmentioning

confidence: 99%

Magnetic-field evolution in a plastically failing neutron-star crust

Lander

Gourgouliatos

2019

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Under normal conditions in a neutron-star crust, ions are locked in place in the crustal lattice and only electrons are mobile, and magnetic-field evolution is thus directly related to the electron velocity. The evolution, however, builds magnetic stresses that can become sufficiently large for the crust to exceed its elastic limit, and to flow plastically. We consider the nature of this plastic flow and the back-reaction on the crustal magnetic field evolution. We formulate a plane-parallel model for the local failure, showing that surface motions are inevitable once the crust yields, in the absence of extra dissipative mechanisms. We perform numerical evolutions of the crustal magnetic field under the joint effect of Hall drift and Ohmic decay, tracking the build-up of magnetic stresses, and diagnosing crustal failure with the von Mises criterion. Beyond this point we solve for the coupled evolution of the plastic velocity and magnetic field. Our results suggest that to have a coexistence of a magnetar corona with small-scale magnetic features, the viscosity of the plastic flow must be roughly 10 36 − 10 37 g cm −1 s −1 . We find significant motion at the surface at a rate of 10 − 100 centimetres per year, and that the localised magnetic field is weaker than in evolutions without plastic flow. We discuss astrophysical implications, and how our local simulations could be used to build a global model of field evolution in the neutron-star crust.

show abstract

“…Our work can be seen as a generic study of the relevance of general relativistic surface degrees of freedom induced by perturbations in stars, not well discussed in the literature to the best of our knowledge, which could lead to new insights into seismology of neutron stars (Krüger et al 2015) and their applications. For example, the possibility of surface degrees of freedom induced by perturbations would change boundary 1 Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Avenida dos Estados, 5001-Bangú, CEP 09210-170, Santo André, SP, Brazil 2 Mathematical Sciences and STAG Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom jonas.pereira@ufabc.edu.br; german.lugones@ufabc.edu.br conditions for perturbations in hybrid stars, which might influence quantities such as their tidal deformabilities (Hinderer 2008;Hinderer et al 2010) and nonradial eigenfrequencies (Miniutti et al 2003;Flores and Lugones 2014).…”

Section: Introductionmentioning

confidence: 99%

General Relativistic Surface Degrees of Freedom in Perturbed Hybrid Stars

Pereira

Lugones²

2019

ApJ

View full text Add to dashboard Cite

We study how the nature of a hybrid system (perfect fluid, solid or a mixture of them) could be related to the induction of general relativistic surface degrees of freedom on phase-splitting surfaces upon perturbation of its phases. We work in the scope of phase conversions in the vicinity of sharp phase transition surfaces whose timescales are either much smaller (rapid conversions) or larger (slow conversions) than the ones of the perturbations (ω −1 , where ω is a characteristic frequency of oscillation of the star). In this first approach, perturbations are assumed to be purely radial. We show that surface degrees of freedom could emerge when either the core or the crust of a hybrid star is solid and phase conversions close to a phase-splitting surface are rapid. We also show how this would change the usual stability rule for solid hybrid stars, namely ∂M 0 /∂ρ c ≥ 0, where M 0 is the total mass to the background hybrid star and ρ c its central density. Further consequences of our analysis for asteroseismology are also briefly discussed.

show abstract

Seismology of adolescent neutron stars: Accounting for thermal effects and crust elasticity

Cited by 63 publications

References 90 publications

Tidal deformations of compact stars with crystalline quark matter

Tidal deformations of compact stars with crystalline quark matter

Magnetic-field evolution in a plastically failing neutron-star crust

General Relativistic Surface Degrees of Freedom in Perturbed Hybrid Stars

Contact Info

Product

Resources

About