1
|
Abstract
A quark-nova is a hypothetical stellar evolution branch where a neutron star converts explosively into a quark star. Here, we discuss the intimate coupling between the micro-physics and macro-physics of the quark-nova and provide a prescription for how to couple the Burn-UD code to the stellar evolution code in order to simulate neutron-star-to-quark-star burning at stellar scales and estimate the resulting energy release and ejecta. Once formed, the thermal evolution of the proto-quark star follows. We found much higher peak neutrino luminosities (>1055 erg/s) and a higher energy neutrino (i.e., harder) spectrum than previous stellar evolution studies of proto-neutron stars. We derived the neutrino counts that observatories such as Super-Kamiokande-III and Halo-II should expect and suggest how these can differentiate between a supernova and a quark-nova. Due to the high peak neutrino luminosities, neutrino pair annihilation can deposit as much as 1052 ergs in kinetic energy in the matter overlaying the neutrinosphere, yielding relativistic quark-nova ejecta. We show how the quark-nova could help us understand many still enigmatic high-energy astrophysical transients, such as super-luminous supernovae, gamma-ray bursts and fast radio bursts.
Collapse
|
2
|
|
3
|
Tan H, Dore T, Dexheimer V, Noronha-Hostler J, Yunes N. Extreme matter meets extreme gravity: Ultraheavy neutron stars with phase transitions. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.105.023018] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
4
|
Bandyopadhyay D. Nuclear astrophysics in our time: supernovae, neutron stars and binary neutron star mergers. THE EUROPEAN PHYSICAL JOURNAL. SPECIAL TOPICS 2021; 230:491-493. [PMID: 34025907 PMCID: PMC8126598 DOI: 10.1140/epjs/s11734-021-00009-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This volume focuses on topical issues in nuclear astrophysics, particularly supernovae, neutron stars, and binary neutron star mergers. An overview of those topics is presented in this editorial. The lasting impact of the Saha equation on astrophysics over the past hundred years is highlighted here.
Collapse
|
5
|
Sun TT, Zheng ZY, Chen H, Burgio GF, Schulze HJ. Equation of state and radial oscillations of neutron stars. Int J Clin Exp Med 2021. [DOI: 10.1103/physrevd.103.103003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
6
|
Hadron–Quark Phase Transition in the SU (3) Local Nambu–Jona-Lasinio (NJL) Model with Vector Interaction. Symmetry (Basel) 2021. [DOI: 10.3390/sym13010124] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We study the hadron–quark hybrid equation of state (EOS) of compact-star matter. The Nambu–Jona-Lasinio (NJL) local SU (3) model with vector-type interaction is used to describe the quark matter phase, while the relativistic mean field (RMF) theory with the scalar-isovector δ-meson effective field is adopted to describe the hadronic matter phase. It is shown that the larger the vector coupling constant GV, the lower the threshold density for the appearance of strange quarks. For a sufficiently small value of the vector coupling constant, the functions of the mass dependence on the baryonic chemical potential have regions of ambiguity that lead to a phase transition in nonstrange quark matter with an abrupt change in the baryon number density. We show that within the framework of the NJL model, the hypothesis on the absolute stability of strange quark matter is not realized. In order to describe the phase transition from hadronic matter to quark matter, Maxwell’s construction is applied. It is shown that the greater the vector coupling, the greater the stiffness of the EOS for quark matter and the phase transition pressure. Our results indicate that the infinitesimal core of the quark phase, formed in the center of the neutron star, is stable.
Collapse
|
7
|
Strong-Interaction Matter under Extreme Conditions from Chiral Quark Models with Nonlocal Separable Interactions. Symmetry (Basel) 2021. [DOI: 10.3390/sym13010121] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We review the current status of the research on effective nonlocal NJL-like chiral quark models with separable interactions, focusing on the application of this approach to the description of the properties of hadronic and quark matter under extreme conditions. The analysis includes the predictions for various hadron properties in vacuum, as well as the study of the features of deconfinement and chiral restoration phase transitions for systems at finite temperature and/or density. We also address other related subjects, such as the study of phase transitions for imaginary chemical potentials, the possible existence of inhomogeneous phase regions, the presence of color superconductivity, the effects produced by strong external magnetic fields and the application to the description of compact stellar objects.
Collapse
|
8
|
Zha S, O'Connor EP, Chu MC, Lin LM, Couch SM. Gravitational-Wave Signature of a First-Order Quantum Chromodynamics Phase Transition in Core-Collapse Supernovae. PHYSICAL REVIEW LETTERS 2020; 125:051102. [PMID: 32794884 DOI: 10.1103/physrevlett.125.051102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
A first-order quantum chromodynamics (QCD) phase transition (PT) may take place in the protocompact star (PCS) produced by a core-collapse supernova (CCSN). In this work, we study the consequences of such a PT in a nonrotating CCSN with axisymmetric hydrodynamic simulations. We find that the PT leads to the collapse of the PCS and results in a loud burst of gravitational waves (GWs). The amplitude of this GW burst is ∼30 times larger than the postbounce GW signal normally found for nonrotating CCSN. It shows a broad peak at high frequencies (∼2500-4000 Hz) in the spectrum, has a duration of ≲5 ms, and carries ∼3 orders of magnitude more energy than the other episodes. Also, the peak frequency of the PCS oscillation increases dramatically after the PT-induced collapse. In addition to a second neutrino burst, the GW signal, if detected by the ground-based GW detectors, is decisive evidence of the first-order QCD PT inside CCSNe and provides key information about the structure and dynamics of the PCS.
Collapse
Affiliation(s)
- Shuai Zha
- The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - Evan P O'Connor
- The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden
| | - Ming-Chung Chu
- Department of Physics and Institute of Theoretical Physics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong S.A.R., China
| | - Lap-Ming Lin
- Department of Physics and Institute of Theoretical Physics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong S.A.R., China
| | - Sean M Couch
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA; Department of Computational Mathematics, Science, and Engineering, Michigan State University, East Lansing, Michigan 48824, USA; Joint Institute for Nuclear Astrophysics-Center for the Evolution of the Elements, Michigan State University, East Lansing, Michigan 48824, USA and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigian 48824, USA
| |
Collapse
|
9
|
Was GW170817 a Canonical Neutron Star Merger? Bayesian Analysis with a Third Family of Compact Stars. UNIVERSE 2020. [DOI: 10.3390/universe6060081] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We investigate the possibility that GW170817 was not the merger of two conventional neutron stars (NS), but involved at least one if not two hybrid stars with a quark matter core that might even belong to a third family of compact stars. To this end, we develop a Bayesian analysis method for selecting the most probable equation of state (EoS) under a set of constraints from compact star physics, which now also include the tidal deformability from GW170817 and the first result for the mass and radius determination for PSR J0030+0451 by the NICER Collaboration. We apply this method for the first time to a two-parameter family of hybrid EoS based on the DD2 model with nucleonic excluded volume for hadronic matter and the color superconducting generalized nlNJL model for quark matter. The model has a variable onset density for deconfinement and can mimic the effects of pasta phases with the possibility of producing a third family of hybrid stars in the mass-radius diagram. The main findings of this study are that: (1) the presence of multiple configurations for a given mass (twins or even triples) corresponds to a set of disconnected lines in the Λ 1 – Λ 2 diagram of tidal deformabilities for binary mergers, so that merger events from the same mass range may result in a probability landscape with different peak positions; (2) the Bayesian analysis with the above observational constraints favors an early onset of the deconfinement transition, at masses of M onset ≤ 0.8 M ⊙ with an M–R relationship that in the range of observed neutron star masses is almost indistinguishable from that of a soft hadronic Akmal, Pandharipande, and Ravenhall (APR) EoS; (3) a few, yet fictitious measurements of the NICER experiment two times more accurate than the present value and a different mass and radius that would change the posterior likelihood so that hybrid EoS with a phase transition onset in the range M onset = 1.1–1.6 M ⊙ would be favored.
Collapse
|
10
|
Weih LR, Hanauske M, Rezzolla L. Postmerger Gravitational-Wave Signatures of Phase Transitions in Binary Mergers. PHYSICAL REVIEW LETTERS 2020; 124:171103. [PMID: 32412268 DOI: 10.1103/physrevlett.124.171103] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/03/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
With the first detection of gravitational waves from a binary system of neutron stars GW170817, a new window was opened to study the properties of matter at and above nuclear-saturation density. Reaching densities a few times that of nuclear matter and temperatures up to 100 MeV, such mergers also represent potential sites for a phase transition (PT) from confined hadronic matter to deconfined quark matter. While the lack of a postmerger signal in GW170817 has prevented us from assessing experimentally this scenario, two theoretical studies have explored the postmerger gravitational-wave signatures of PTs in mergers of a binary system of neutron stars. We here extend and complete the picture by presenting a novel signature of the occurrence of a PT. More specifically, using fully general-relativistic hydrodynamic simulations and employing a suitably constructed equation of state that includes a PT, we present the occurrence of a "delayed PT," i.e., a PT that develops only some time after the merger and produces a metastable object with a quark-matter core, i.e., a hypermassive hybrid star. Because in this scenario, the postmerger signal exhibits two distinct fundamental gravitational-wave frequencies-before and after the PT-the associated signature promises to be the strongest and cleanest among those considered so far, and one of the best signatures of the production of quark matter in the present Universe.
Collapse
Affiliation(s)
- Lukas R Weih
- Institut für Theoretische Physik, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - Matthias Hanauske
- Institut für Theoretische Physik, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
- Frankfurt Institute for Advanced Studies, Ruth-Moufang-Straße 1, 60438 Frankfurt, Germany
| | - Luciano Rezzolla
- Institut für Theoretische Physik, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
- School of Mathematics, Trinity College, Dublin 2, Ireland
| |
Collapse
|
11
|
Abstract
We study a specific model of neutron star matter that supports a phase transition to quark matter at high density and examine parameter ranges for consistency with the mass-weighted tidal deformability of Λ ˜ = 300 − 230 + 420 for a mass ratio of q ∈ [ 0.73 , 1.0 ] , as inferred from observations of gravitational waves from the binary neutron star merger event GW170817. By using this observation to restrict the parameter space for the equation of state (EoS) model used throughout this study, we aim to assess the possibility of a potential solution to the masquerade and flavor camouflage problems for hybrid EoS models. Assuming the two stars have the same EoS, in which the Dirac-Brueckner-Hartree Fock (DBHF) nuclear model transitions to the vBag quark model, we see if the parameter space of these hybrid model stars are restricted due to the adherence to the reported Λ 1.4 ∈ 70 , 580 and M m a x ∈ [ 2.01 , 2.16 ] M ⊙ constraints. Upon completion, we find that, while the parameter space for our model does get restricted, it does not ultimately resolve the masquerade and flavor camouflage problems.
Collapse
|
12
|
Abstract
In the first part of this paper, we investigate the possible existence of a structured hadron-quark mixed phase in the cores of neutron stars. This phase, referred to as the hadron-quark pasta phase, consists of spherical blob, rod, and slab rare phase geometries. Particular emphasis is given to modeling the size of this phase in rotating neutron stars. We use the relativistic mean-field theory to model hadronic matter and the non-local three-flavor Nambu–Jona-Lasinio model to describe quark matter. Based on these models, the hadron-quark pasta phase exists only in very massive neutron stars, whose rotational frequencies are less than around 300 Hz. All other stars are not dense enough to trigger quark deconfinement in their cores. Part two of the paper deals with the quark-hadron composition of hot (proto) neutron star matter. To this end we use a local three-flavor Polyakov–Nambu–Jona-Lasinio model which includes the ’t Hooft (quark flavor mixing) term. It is found that this term leads to non-negligible changes in the particle composition of (proto) neutron stars made of hadron-quark matter.
Collapse
|
13
|
The Structure of Cold Neutron Star With a Quark Core Within the MIT and NJL Models. IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY, TRANSACTIONS A: SCIENCE 2019. [DOI: 10.1007/s40995-019-00731-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
14
|
McLerran L, Reddy S. Quarkyonic Matter and Neutron Stars. PHYSICAL REVIEW LETTERS 2019; 122:122701. [PMID: 30978062 DOI: 10.1103/physrevlett.122.122701] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 02/19/2019] [Indexed: 06/09/2023]
Abstract
We consider quarkyonic matter to naturally explain the observed properties of neutron stars. We argue that such matter might exist at densities close to that of nuclear matter, and at the onset, the pressure and the sound velocity in quarkyonic matter increase rapidly. In the limit of large number of quark colors N_{c}, this transition is characterized by a discontinuous change in pressure as a function of baryon number density. We make a simple model of quarkyonic matter and show that generically the sound velocity is a nonmonotonic function of density-it reaches a maximum at relatively low density, decreases, and then increases again to its asymptotic value of 1/sqrt[3].
Collapse
Affiliation(s)
- Larry McLerran
- Institute for Nuclear Theory and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Sanjay Reddy
- Institute for Nuclear Theory and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
15
|
Abstract
First-order phase transitions, such as the liquid-gas transition, proceed via formation of structures, such as bubbles and droplets. In strongly interacting compact star matter, at the crust-core transition but also the hadron-quark transition in the core, these structures form different shapes dubbed “pasta phases”. We describe two methods to obtain one-parameter families of hybrid equations of state (EoS) substituting the Maxwell construction that mimic the thermodynamic behaviour of pasta phase in between a low-density hadron and a high-density quark matter phase without explicitly computing geometrical structures. Both methods reproduce the Maxwell construction as a limiting case. The first method replaces the behaviour of pressure against chemical potential in a finite region around the critical pressure of the Maxwell construction by a polynomial interpolation. The second method uses extrapolations of the hadronic and quark matter EoS beyond the Maxwell point to define a mixing of both with weight functions bounded by finite limits around the Maxwell point. We apply both methods to the case of a hybrid EoS with a strong first order transition that entails the formation of a third family of compact stars and the corresponding mass twin phenomenon. For both models, we investigate the robustness of this phenomenon against variation of the single parameter: the pressure increment at the critical chemical potential that quantifies the deviation from the Maxwell construction. We also show sets of results for compact star observables other than mass and radius, namely the moment of inertia and the baryon mass.
Collapse
|
16
|
|
17
|
|
18
|
Bai Z, Chen H, Liu YX. Revisiting the equation of state of hybrid stars in the Dyson-Schwinger equation approach to QCD. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.97.023018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
19
|
Lavagno A. Nuclear phase transition and thermodynamic instabilities in dense nuclear matter. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201818203007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We study the presence of thermodynamic instabilities in a nuclear medium at finite temperature and density where nuclear phase transitions can take place. Such a phase transition is characterized by pure hadronic matter with both mechanical instability (fluctuations on the baryon density) that by chemical-diffusive instability (fluctuations on the electric charge concentration). Similarly to the liquid-gas phase transition, the nucleonic and the Δ-matter phase have a different isospin density in the mixed phase. In the liquid-gas phase transition, the process of producing a larger neutron excess in the gas phase is referred to as isospin fractionation. A similar effects can occur in the nucleon-Δ matter phase transition due essentially to a Δ- excess in the Δ-matter phase in asymmetric nuclear matter. In this context we also discuss the relevance of Δ-isobar and hyperon degrees of freedom in the bulk properties of the protoneutron stars at fixed entropy per baryon, in the presence and in the absence of trapped neutrinos.
Collapse
|
20
|
|
21
|
Shao G, Tang Z, Di Toro M, Colonna M, Gao X, Gao N, Zhao Y. Entanglement interaction and the phase diagram of strongly interacting matter. Int J Clin Exp Med 2015. [DOI: 10.1103/physrevd.92.114027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
22
|
Moreira J, Morais J, Hiller B, Osipov A, Blin A. Strange quark matter in the presence of explicit symmetry breaking interactions. Int J Clin Exp Med 2015. [DOI: 10.1103/physrevd.91.116003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
23
|
Zhao T, Yan Y, Luo XL, Zong HS. Study of rotational quark stars and hybrid stars based on the latest equation of state and observation data. Int J Clin Exp Med 2015. [DOI: 10.1103/physrevd.91.034018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
24
|
Wang H, Liu G, Wu Y, Xu Y, Zhu M, Bao T. The third family of compact stars with the color-flavor locked quark core. CHINESE SCIENCE BULLETIN-CHINESE 2013. [DOI: 10.1007/s11434-013-5983-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
25
|
Bhattacharyya A, Ghosh SK, Majumder S, Ray R. Study of beta equilibrated2+1flavor quark matter in the Polyakov-Nambu-Jona-Lasinio model. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.86.096006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
26
|
Yasutake N, Maruyama T, Tatsumi T. Amorphous state in the mixed phase of hadron-quark phase transition in protoneutron stars. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.86.101302] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
27
|
Shao GY, Colonna M, Di Toro M, Liu B, Matera F. Influence of vector interactions on the hadron-quark/gluon phase transition. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.114017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
28
|
Banik S, Bandyopadhyay D. Effect of shear viscosity on the nucleation of antikaon condensed matter in neutron stars. Int J Clin Exp Med 2010. [DOI: 10.1103/physrevd.82.123010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
29
|
Pagliara G, Schaffner-Bielich J. Hadron-quark phase transition at nonzero isospin density: The effect of quark pairing. Int J Clin Exp Med 2010. [DOI: 10.1103/physrevd.81.094024] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
30
|
Pagliara G, Hempel M, Schaffner-Bielich J. New possible quark-hadron mixed phase in protoneutron stars. PHYSICAL REVIEW LETTERS 2009; 103:171102. [PMID: 19905743 DOI: 10.1103/physrevlett.103.171102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Indexed: 05/28/2023]
Abstract
The transition from hadronic to quark matter at high density is a strong first order phase transition if the surface tension between the two phases is large. While this implies a constant-pressure mixed phase in cold neutron star matter this is not the case for the hot and lepton rich matter of protoneutron stars. By considering the global conservation of lepton number during the stage of neutrino trapping, we show that a new mixed phase with non-constant pressure could appear in protoneutron stars and it would gradually disappear during deleptonization. We discuss the peculiar properties of this mixed phase and its possible significant effects on the evolution of protoneutron stars and their neutrino emission.
Collapse
Affiliation(s)
- G Pagliara
- Institut für Theoretische Physik, Ruprecht-Karls-Universität, Philosophenweg 16, D-69120, Heidelberg, Germany
| | | | | |
Collapse
|
31
|
Burgio GF, Plumari S. Structure of hybrid protoneutron stars within the Nambu–Jona-Lasinio model. Int J Clin Exp Med 2008. [DOI: 10.1103/physrevd.77.085022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
32
|
Bonanno L, Drago A, Lavagno A. Softening of the equation of state of matter at large densities and temperatures: chiral-symmetry restoration versus quark deconfinement. PHYSICAL REVIEW LETTERS 2007; 99:242301. [PMID: 18233442 DOI: 10.1103/physrevlett.99.242301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 09/20/2007] [Indexed: 05/25/2023]
Abstract
We discuss two models in which a softening of the equation of state takes place due to the appearance of new degrees of freedom. The first is a hadronic model in which the softening is due to chiral symmetry restoration. In the second model the softening is associated with the formation of clusters of quarks in the mixed phase. We show that in the first case the bulk modulus is mainly dependent on the density, while in the mixed-phase model the bulk modulus strongly depends on the temperature and it is not vanishing due to the presence of two conserved charges, the baryon and the isospin one.
Collapse
Affiliation(s)
- Luca Bonanno
- Dipartimento di Fisica, Università di Ferrara and INFN, Sezione di Ferrara, 44100 Ferrara, Italy
| | | | | |
Collapse
|
33
|
Jaikumar P, Reddy S, Steiner AW. Strange star surface: a crust with nuggets. PHYSICAL REVIEW LETTERS 2006; 96:041101. [PMID: 16486800 DOI: 10.1103/physrevlett.96.041101] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Indexed: 05/06/2023]
Abstract
We reexamine the surface composition of strange stars. Strange quark stars are hypothetical compact stars which could exist if strange quark matter was absolutely stable. It is widely accepted that they are characterized by an enormous density gradient (10(26) g/cm4) and large electric fields at the surface. By investigating the possibility of realizing a heterogeneous crust, comprised of nuggets of strange quark matter embedded in an uniform electron background, we find that the strange star surface has a much reduced density gradient and negligible electric field. We comment on how our findings will impact various proposed observable signatures for strange stars.
Collapse
Affiliation(s)
- Prashanth Jaikumar
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | | | | |
Collapse
|
34
|
Owen BJ. Maximum elastic deformations of compact stars with exotic equations of state. PHYSICAL REVIEW LETTERS 2005; 95:211101. [PMID: 16384127 DOI: 10.1103/physrevlett.95.211101] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2004] [Revised: 04/13/2005] [Indexed: 05/05/2023]
Abstract
I make the first estimates of maximum elastic quadrupole deformations sustainable by alternatives to conventional neutron stars. Solid strange quark stars might sustain maximum ellipticities (dimensionless quadrupoles) up to a few times rather than a few times for conventional neutron stars, and hybrid quark-baryon or meson-condensate stars might sustain up to . Most of the difference is due to the shear modulus, which can be up to rather than in the inner crust of a conventional neutron star. Maximum solid strange star ellipticities are comparable to upper limits obtained for several known pulsars in a recent gravitational-wave search by LIGO. Maximum ellipticities of the more robust hybrid model will be detectable by LIGO at initial design sensitivity. A large shear modulus also strengthens the case for starquakes as an explanation for frequent pulsar glitches.
Collapse
Affiliation(s)
- Benjamin J Owen
- Center for Gravitational Wave Physics, Institute for Gravitational Physics and Geometry, and Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802-6300, USA
| |
Collapse
|
35
|
Lattimer JM, Prakash M. Ultimate energy density of observable cold baryonic matter. PHYSICAL REVIEW LETTERS 2005; 94:111101. [PMID: 15903841 DOI: 10.1103/physrevlett.94.111101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Indexed: 05/02/2023]
Abstract
We demonstrate that the largest measured mass of a neutron star establishes an upper bound to the energy density of observable cold baryonic matter. An equation of state-independent expression satisfied by both normal neutron stars and self-bound quark matter stars is derived for the largest energy density of matter inside stars as a function of their masses. The largest observed mass sets the lowest upper limit to the density. Implications from existing and future neutron star mass measurements are discussed.
Collapse
Affiliation(s)
- James M Lattimer
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| | | |
Collapse
|
36
|
Abstract
Neutron stars are some of the densest manifestations of massive objects in the universe. They are ideal astrophysical laboratories for testing theories of dense matter physics and provide connections among nuclear physics, particle physics, and astrophysics. Neutron stars may exhibit conditions and phenomena not observed elsewhere, such as hyperon-dominated matter, deconfined quark matter, superfluidity and superconductivity with critical temperatures near 10(10) kelvin, opaqueness to neutrinos, and magnetic fields in excess of 10(13) Gauss. Here, we describe the formation, structure, internal composition, and evolution of neutron stars. Observations that include studies of pulsars in binary systems, thermal emission from isolated neutron stars, glitches from pulsars, and quasi-periodic oscillations from accreting neutron stars provide information about neutron star masses, radii, temperatures, ages, and internal compositions.
Collapse
Affiliation(s)
- J M Lattimer
- Department of Physics and Astronomy, State University of New York, Stony Brook, NY 11794-3800, USA.
| | | |
Collapse
|
37
|
Bedaque PF, Caldas H, Rupak G. Phase separation in asymmetrical fermion superfluids. PHYSICAL REVIEW LETTERS 2003; 91:247002. [PMID: 14683148 DOI: 10.1103/physrevlett.91.247002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Indexed: 05/24/2023]
Abstract
Motivated by recent developments on cold atom traps and high density QCD we consider fermionic systems composed of two particle species with different densities. We argue that a mixed phase composed of normal and superfluid components is the energetically favored ground state. We suggest how this phase separation can be used as a probe of fermion superfluidity in atomic traps.
Collapse
Affiliation(s)
- Paulo F Bedaque
- Lawrence-Berkeley Laboratory, Berkeley, California 94720, USA
| | | | | |
Collapse
|
38
|
Prakash M, Lattimer JM, Pons JA, Steiner AW, Reddy S. Evolution of a Neutron Star from Its Birth to Old Age. ACTA ACUST UNITED AC 2001. [DOI: 10.1007/3-540-44578-1_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
|
39
|
Pons JA, Steiner AW, Prakash M, Lattimer JM. Evolution of proto-neutron stars with quarks. PHYSICAL REVIEW LETTERS 2001; 86:5223-5226. [PMID: 11384463 DOI: 10.1103/physrevlett.86.5223] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2001] [Indexed: 05/23/2023]
Abstract
Neutrino fluxes from proto-neutron stars with and without quarks are studied. Observable differences become apparent after 10-20 s of evolution. Sufficiently massive stars containing negatively charged, strongly interacting, particles collapse to black holes during the first minute of evolution. Since the neutrino flux vanishes when a black hole forms, this is the most obvious signal that quarks (or other types of strange matter) have appeared. The metastability time scales for stars with quarks are intermediate between those containing hyperons and kaon condensates.
Collapse
Affiliation(s)
- J A Pons
- Department of Physics and Astronomy, SUNY at Stony Brook, Stony Brook, New York 11794-3800, USA
| | | | | | | |
Collapse
|
40
|
Rajagopal K, Wilczek F. Enforced electrical neutrality of the color-flavor locked phase. PHYSICAL REVIEW LETTERS 2001; 86:3492-3495. [PMID: 11328006 DOI: 10.1103/physrevlett.86.3492] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2000] [Indexed: 05/23/2023]
Abstract
We demonstrate that quark matter in the color-flavor locked phase of QCD is rigorously electrically neutral, despite the unequal quark masses, and even in the presence of an electron chemical potential. As long as the strange quark mass and the electron chemical potential do not preclude the color-flavor locked phase, quark matter is automatically neutral. No electrons are required and none are admitted.
Collapse
Affiliation(s)
- K Rajagopal
- Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | |
Collapse
|
41
|
Epsztein Grynberg S, Nemes MC, Rodrigues H, Chiapparini M, Duarte SB, Blin AH, Hiller B. Neutrino trapping and hybrid protoneutron star formation. Int J Clin Exp Med 2000. [DOI: 10.1103/physrevd.62.123003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
42
|
Page D, Prakash M, Lattimer JM, Steiner AW. Prospects of detecting baryon and quark superfluidity from cooling neutron stars. PHYSICAL REVIEW LETTERS 2000; 85:2048-2051. [PMID: 10970460 DOI: 10.1103/physrevlett.85.2048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2000] [Indexed: 05/23/2023]
Abstract
Baryon and quark superfluidity in the cooling of neutron stars are investigated. Future observations will allow us to constrain combinations of the neutron or Lambda-hyperon pairing gaps and the star's mass. However, in a hybrid star with a mixed phase of hadrons and quarks, quark gaps larger than a few tenths of an MeV render quark matter virtually invisible for cooling. If the quark gap is smaller, quark superfluidity could be important, but its effects will be nearly impossible to distinguish from those of other baryonic constituents.
Collapse
Affiliation(s)
- D Page
- Instituto de Astronomia, UNAM, Mexico D.F. 04510, Mexico
| | | | | | | |
Collapse
|
43
|
Heiselberg H, Hjorth-Jensen M. Phase Transitions in Neutron Stars and Maximum Masses. THE ASTROPHYSICAL JOURNAL 1999; 525:L45-L48. [PMID: 10511510 DOI: 10.1086/312321] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Using the most recent realistic effective interactions for nuclear matter with a smooth extrapolation to high densities including causality, we constrain the equation of state and calculate maximum masses of rotating neutron stars. First- and second-order phase transitions to, e.g., quark matter at high densities are included. If neutron star masses of approximately 2.3 M middle dot in circle from quasi-periodic oscillations in low-mass X-ray binaries are confirmed, a soft equation of state as well as strong phase transitions can be excluded in neutron star cores.
Collapse
|
44
|
Bandyopadhyay D, Chakrabarty S, Dey P, Pal S. Rapid cooling of magnetized neutron stars. Int J Clin Exp Med 1998. [DOI: 10.1103/physrevd.58.121301] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
45
|
Müller H, Serot BD. Phase transitions in warm, asymmetric nuclear matter. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1995; 52:2072-2091. [PMID: 9970723 DOI: 10.1103/physrevc.52.2072] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
46
|
Glendenning NK, Pei S. Crystalline structure of the mixed confined-deconfined phase in neutron stars. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1995; 52:2250-2253. [PMID: 9970744 DOI: 10.1103/physrevc.52.2250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
47
|
Prakash M, Cooke JR, Lattimer JM. Quark-hadron phase transition in protoneutron stars. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1995; 52:661-665. [PMID: 10019287 DOI: 10.1103/physrevd.52.661] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
48
|
|
49
|
Madsen J. Shell model versus liquid drop model for strangelets. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 50:3328-3331. [PMID: 10017968 DOI: 10.1103/physrevd.50.3328] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
50
|
Heiselberg H. Screening in quark droplets. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1993; 48:1418-1423. [PMID: 10016374 DOI: 10.1103/physrevd.48.1418] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|