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Title: Signatures for quark matter from multi-messenger observations


In this article we review the prospects for detecting quark matter in neutron star cores. We survey the proposed signatures and emphasize the importance of data from neutron star mergers, which provide access to dynamical properties that operate on short timescales that are not probed by most other neutron star observables.

ORCiD logo [1]; ORCiD logo [2];  [3]
  1. Washington Univ., St. Louis, MO (United States)
  2. Ohio Univ., Athens, OH (United States); Univ. of California, Berkeley, CA (United States)
  3. Istanbul Univ., Istanbul (Turkey)
Publication Date:
Research Org.:
Washington Univ., St. Louis, MO (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP)
OSTI Identifier:
Grant/Contract Number:  
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Physics. G, Nuclear and Particle Physics
Additional Journal Information:
Journal Volume: 46; Journal Issue: 11; Journal ID: ISSN 0954-3899
IOP Publishing
Country of Publication:
United States

Citation Formats

Alford, Mark G., Han, Sophia, and Schwenzer, Kai. Signatures for quark matter from multi-messenger observations. United States: N. p., 2019. Web. doi:10.1088/1361-6471/ab337a.
Alford, Mark G., Han, Sophia, & Schwenzer, Kai. Signatures for quark matter from multi-messenger observations. United States. doi:
Alford, Mark G., Han, Sophia, and Schwenzer, Kai. Fri . "Signatures for quark matter from multi-messenger observations". United States. doi:
title = {Signatures for quark matter from multi-messenger observations},
author = {Alford, Mark G. and Han, Sophia and Schwenzer, Kai},
abstractNote = {In this article we review the prospects for detecting quark matter in neutron star cores. We survey the proposed signatures and emphasize the importance of data from neutron star mergers, which provide access to dynamical properties that operate on short timescales that are not probed by most other neutron star observables.},
doi = {10.1088/1361-6471/ab337a},
journal = {Journal of Physics. G, Nuclear and Particle Physics},
number = 11,
volume = 46,
place = {United States},
year = {2019},
month = {10}

Journal Article:
Free Publicly Available Full Text
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Cited by: 6 works
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Figures / Tables:

Figure 1 Figure 1: Conjectured diagram of phases of matter as a function of baryon chemical potential µ and temperature T . At the highest densities, we expect the color-flavor-locked (CFL) phase of quark matter.

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Works referenced in this record:

Discovery of a Second Transient Low-Mass X-Ray Binary in the Globular Cluster ngc 6440
journal, April 2010

Inhomogeneous superconductivity in condensed matter and QCD
journal, February 2004

Maximum mass and radius of neutron stars, and the nuclear symmetry energy
journal, March 2012

Chandra studies of the globular cluster 47 Tucanae: a deeper X-ray source catalogue, five new X-ray counterparts to millisecond radio pulsars and new constraints to r-mode instability window
journal, September 2017

  • Bhattacharya, Souradeep; Heinke, Craig O.; Chugunov, Andrey I.
  • Monthly Notices of the Royal Astronomical Society, Vol. 472, Issue 3
  • DOI: 10.1093/mnras/stx2241

Masses, Radii, and the Equation of State of Neutron Stars
journal, September 2016

Symmetry Parameter Constraints from a Lower Bound on Neutron-matter Energy
journal, October 2017

  • Tews, Ingo; Lattimer, James M.; Ohnishi, Akira
  • The Astrophysical Journal, Vol. 848, Issue 2
  • DOI: 10.3847/1538-4357/aa8db9

Surface tension of dense matter at the chiral phase transition
journal, January 2019

Phase transitions and the mass-radius curves of relativistic stars
journal, June 1998

Rigidity of crystalline color superconducting quark matter
journal, October 2007

Neutron Skins and Neutron Stars in the Multimessenger Era
journal, April 2018

Constraints on Neutron Star Radii Based on Chiral Effective Field Theory Interactions
journal, October 2010

Constraining the Speed of Sound inside Neutron Stars with Chiral Effective Field Theory Interactions and Observations
journal, June 2018

Implications from GW170817 and I-Love-Q relations for relativistic hybrid stars
journal, April 2018

Strange stars as persistent sources of gravitational waves
journal, December 2002

Binary neutron star mergers: a review of Einstein’s richest laboratory
journal, July 2017

Nucleation of quark matter in protoneutron star matter
journal, June 2010

Constraining the Equation of State with Moment of Inertia Measurements
journal, August 2005

  • Lattimer, James M.; Schutz, Bernard F.
  • The Astrophysical Journal, Vol. 629, Issue 2
  • DOI: 10.1086/431543

QCD and strongly coupled gauge theories: challenges and perspectives
journal, October 2014

Gravitational wave Emission and Spin-Down of Young Pulsars
journal, January 2014

Phase conversion dissipation in multicomponent compact stars
journal, May 2015

Direct URCA process in neutron stars
journal, May 1991

Strange Star Surface: A Crust with Nuggets
journal, January 2006

journal, October 2013

journal, August 2013

Measurement of the Neutron Radius of Pb 208 through Parity Violation in Electron Scattering
journal, March 2012

Stability of strange star crusts and strangelets
journal, June 2006

Holographic compact stars meet gravitational wave constraints
journal, December 2018

  • Annala, Eemeli; Ecker, Christian; Hoyos, Carlos
  • Journal of High Energy Physics, Vol. 2018, Issue 12
  • DOI: 10.1007/JHEP12(2018)078

Characteristics of hybrid compact stars with a sharp hadron-quark interface
journal, March 2016

The Low Quiescent X‐Ray Luminosity of the Neutron Star Transient XTE J2123−058
journal, August 2004

  • Tomsick, John A.; Gelino, Dawn M.; Halpern, Jules P.
  • The Astrophysical Journal, Vol. 610, Issue 2
  • DOI: 10.1086/421865

Minimal color-flavor-locked–nuclear interface
journal, September 2001

Tidal deformations of compact stars with crystalline quark matter
journal, May 2017

Unlocking color and flavor in superconducting strange quark matter
journal, October 1999

GW170817: Joint Constraint on the Neutron Star Equation of State from Multimessenger Observations
journal, January 2018

  • Radice, David; Perego, Albino; Zappa, Francesco
  • The Astrophysical Journal, Vol. 852, Issue 2
  • DOI: 10.3847/2041-8213/aaa402

Saturation of the r ‐Mode Instability
journal, July 2003

  • Arras, Phil; Flanagan, Eanna E.; Morsink, Sharon M.
  • The Astrophysical Journal, Vol. 591, Issue 2
  • DOI: 10.1086/374657

Gravitational radiation from crystalline color-superconducting hybrid stars
journal, April 2009

Crystallography of three-flavor quark matter
journal, November 2006

Color superconductivity in dense quark matter
journal, November 2008

  • Alford, Mark G.; Schmitt, Andreas; Rajagopal, Krishna
  • Reviews of Modern Physics, Vol. 80, Issue 4
  • DOI: 10.1103/RevModPhys.80.1455

Effect of a neutron-star crust on the r-mode instability
journal, September 2000

Viscous damping of r-modes: Small amplitude instability
journal, January 2012

Minimal Cooling of Neutron Stars: A New Paradigm
journal, December 2004

  • Page, Dany; Lattimer, James M.; Prakash, Madappa
  • The Astrophysical Journal Supplement Series, Vol. 155, Issue 2
  • DOI: 10.1086/424844

Tidal Deformability from GW170817 as a Direct Probe of the Neutron Star Radius
journal, April 2018

  • Raithel, Carolyn A.; Özel, Feryal; Psaltis, Dimitrios
  • The Astrophysical Journal, Vol. 857, Issue 2
  • DOI: 10.3847/2041-8213/aabcbf

Approximate universal relations for neutron stars and quark stars
journal, April 2017

Color-flavor locking and chiral symmetry breaking in high density QCD
journal, January 1999

Gravitational Radiation and Rotation of Accreting Neutron Stars
journal, July 1998

  • Bildsten, Lars
  • The Astrophysical Journal, Vol. 501, Issue 1
  • DOI: 10.1086/311440

Phase diagrams of lattice gauge theories with Higgs fields
journal, June 1979

Neutrino Emission from Cooper Pairs and Minimal Cooling of Neutron Stars
journal, December 2009

What the Timing of Millisecond Pulsars Can Teach us about Their Interior
journal, December 2014

Cosmic separation of phases
journal, July 1984

The Nanograv Nine-Year data set: mass and Geometric Measurements of Binary Millisecond Pulsars
journal, December 2016

  • Fonseca, Emmanuel; Pennucci, Timothy T.; Ellis, Justin A.
  • The Astrophysical Journal, Vol. 832, Issue 2
  • DOI: 10.3847/0004-637X/832/2/167

Properties of the Binary Neutron Star Merger GW170817
journal, January 2019

The Australia Telescope National Facility Pulsar Catalogue
journal, April 2005

  • Manchester, R. N.; Hobbs, G. B.; Teoh, A.
  • The Astronomical Journal, Vol. 129, Issue 4
  • DOI: 10.1086/428488

Nambu–Jona-Lasinio model of dense three-flavor matter with axial anomaly: The low temperature critical point and BEC-BCS diquark crossover
journal, June 2010

Gravitational Radiation Instability in Hot Young Neutron Stars
journal, June 1998

An introduction to quantum order, string-net condensation, and emergence of light and fermions
journal, March 2005

Cooling of Accretion-Heated Neutron Stars
journal, September 2017

  • Wijnands, Rudy; Degenaar, Nathalie; Page, Dany
  • Journal of Astrophysics and Astronomy, Vol. 38, Issue 3
  • DOI: 10.1007/s12036-017-9466-5

A two-solar-mass neutron star measured using Shapiro delay
journal, October 2010

  • Demorest, P. B.; Pennucci, T.; Ransom, S. M.
  • Nature, Vol. 467, Issue 7319
  • DOI: 10.1038/nature09466

Topological Lifshitz transitions
journal, January 2017

Quark Beta Decay and the Cooling of Neutron Stars
journal, June 1980

Shear viscosity in neutron star cores
journal, September 2008

Thickness of the strangelet-crystal crust of a strange star
journal, October 2008

Crystalline color superconductivity
journal, March 2001

Bulk viscosity of hot neutron-star matter and the maximum rotation rates of neutron stars
journal, June 1989

Static Solutions of Einstein's Field Equations for Spheres of Fluid
journal, February 1939

Are Neutron Stars with Crystalline Color-Superconducting Cores Relevant for the LIGO Experiment?
journal, December 2007

New Constraints on Radii and Tidal Deformabilities of Neutron Stars from GW170817
journal, June 2018

Transport and relaxation in degenerate quark plasmas
journal, September 1993

From hadrons to quarks in neutron stars: a review
journal, March 2018

  • Baym, Gordon; Hatsuda, Tetsuo; Kojo, Toru
  • Reports on Progress in Physics, Vol. 81, Issue 5
  • DOI: 10.1088/1361-6633/aaae14

Signals in the tidal deformability for phase transitions in compact stars with constraints from GW170817
journal, January 2019

  • Christian, Jan-Erik; Zacchi, Andreas; Schaffner-Bielich, Jürgen
  • Physical Review D, Vol. 99, Issue 2
  • DOI: 10.1103/PhysRevD.99.023009

Lower limit on the heat capacity of the neutron star core
journal, February 2017

A Massive Pulsar in a Compact Relativistic Binary
journal, April 2013

Constraining Strangeness in Dense Matter with GW170817
journal, June 2019

Crystalline color superconductors
journal, April 2014

  • Anglani, Roberto; Casalbuoni, Roberto; Ciminale, Marco
  • Reviews of Modern Physics, Vol. 86, Issue 2
  • DOI: 10.1103/RevModPhys.86.509

GW170817: Measurements of Neutron Star Radii and Equation of State
journal, October 2018

Tidal and tidal-resonant effects in coalescing binaries
journal, July 1995

  • Kokkotas, Kostas D.; Schäfer, Gerhard
  • Monthly Notices of the Royal Astronomical Society, Vol. 275, Issue 2
  • DOI: 10.1093/mnras/275.2.301

Hadron–quark crossover and massive hybrid stars
journal, July 2013

  • Masuda, Kota; Hatsuda, Tetsuo; Takatsuka, Tatsuyuki
  • Progress of Theoretical and Experimental Physics, Vol. 2013, Issue 7
  • DOI: 10.1093/ptep/ptt045

Thermal state of transiently accreting neutron stars
journal, August 2003

Equation of state of a dense and magnetized fermion system
journal, December 2010

Quark deconfinement transition in hyperonic matter
journal, January 2008

Sound Velocity Bound and Neutron Stars
journal, January 2015

Models of pulsar glitches
journal, February 2015

  • Haskell, Brynmor; Melatos, Andrew
  • International Journal of Modern Physics D, Vol. 24, Issue 03
  • DOI: 10.1142/S0218271815300086

Third family of compact stars within a nonlocal chiral quark model equation of state
journal, March 2019

  • Alvarez-Castillo, D. E.; Blaschke, D. B.; Grunfeld, A. G.
  • Physical Review D, Vol. 99, Issue 6
  • DOI: 10.1103/PhysRevD.99.063010

Constraining the mass and radius of neutron stars in globular clusters
journal, January 2018

  • Steiner, A. W.; Heinke, C. O.; Bogdanov, S.
  • Monthly Notices of the Royal Astronomical Society, Vol. 476, Issue 1
  • DOI: 10.1093/mnras/sty215

Neutrino emissivities of neutron stars
journal, September 1979

  • Friman, B. L.; Maxwell, O. V.
  • The Astrophysical Journal, Vol. 232
  • DOI: 10.1086/157313

Measuring Neutron star Radii via Pulse Profile Modeling with Nicer
journal, November 2016

  • Özel, Feryal; Psaltis, Dimitrios; Arzoumanian, Zaven
  • The Astrophysical Journal, Vol. 832, Issue 1
  • DOI: 10.3847/0004-637X/832/1/92

Region of a hadron-quark mixed phase in hybrid stars
journal, June 2011

Rapid Neutrino Cooling in the Neutron Star MXB 1659-29
journal, April 2018

Effects of Strong Magnetic Fields on Neutron Star Structure
journal, June 2001

  • Cardall, Christian Y.; Prakash, Madappa; Lattimer, James M.
  • The Astrophysical Journal, Vol. 554, Issue 1
  • DOI: 10.1086/321370

Phase transitions in dense matter and the maximum mass of neutron stars
journal, April 2013

Quarkyonic Matter and Neutron Stars
journal, March 2019

Two-layer compact stars with crystalline quark matter: Screening effect on the tidal deformability
journal, January 2019

Signatures of Quark-Hadron Phase Transitions in General-Relativistic Neutron-Star Mergers
journal, February 2019

Identifying a First-Order Phase Transition in Neutron-Star Mergers through Gravitational Waves
journal, February 2019

Continuity of Quark and Hadron Matter
journal, May 1999

Breaking Strain of Neutron Star Crust and Gravitational Waves
journal, May 2009

Constraining twin stars with GW170817
journal, May 2019

Quasi-Normal Modes of Stars and Black Holes
journal, September 1999

  • Kokkotas, Kostas D.; Schmidt, Bernd G.
  • Living Reviews in Relativity, Vol. 2, Issue 1
  • DOI: 10.12942/lrr-1999-2

Surface tension and curvature energy of quark matter in the Nambu–Jona-Lasinio model
journal, October 2013

Strange stars
journal, November 1986

  • Alcock, Charles; Farhi, Edward; Olinto, Angela
  • The Astrophysical Journal, Vol. 310
  • DOI: 10.1086/164679

Tidal deformabilities and neutron star mergers
journal, September 2018

X-ray bounds on the r-mode amplitude in millisecond pulsars
journal, December 2016

  • Schwenzer, Kai; Boztepe, Tuğba; Güver, Tolga
  • Monthly Notices of the Royal Astronomical Society, Vol. 466, Issue 3
  • DOI: 10.1093/mnras/stw3201

On Massive Neutron Cores
journal, February 1939

Signatures of hadron-quark mixed phase in gravitational waves
journal, January 2011

Constraints on the hybrid equation of state with a crossover hadron-quark phase transition in the light of GW170817
journal, October 2018

Crustal Heating and Quiescent Emission from Transiently Accreting Neutron Stars
journal, September 1998

  • Brown, Edward F.; Bildsten, Lars; Rutledge, Robert E.
  • The Astrophysical Journal, Vol. 504, Issue 2
  • DOI: 10.1086/311578

Tidal deformability and other global parameters of compact stars with strong phase transitions
journal, February 2019

Gravitational wave emission from oscillating millisecond pulsars
journal, December 2014

  • Alford, Mark G.; Schwenzer, Kai
  • Monthly Notices of the Royal Astronomical Society, Vol. 446, Issue 4
  • DOI: 10.1093/mnras/stu2361

The spin Parameter of Uniformly Rotating Compact Stars
journal, January 2011

GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
journal, October 2017

A New Class of Unstable Modes of Rotating Relativistic Stars
journal, August 1998

  • Andersson, Nils
  • The Astrophysical Journal, Vol. 502, Issue 2
  • DOI: 10.1086/305919

The Quarkyonic star
journal, February 2016

Hybrid Stars in the Light of GW170817
journal, April 2018

Viscous Dissipation and Heat Conduction in Binary Neutron-Star Mergers
journal, January 2018

Cold equation of state in a strong magnetic field - Effects of inverse beta-decay
journal, December 1991

  • Lai, Dong; Shapiro, Stuart L.
  • The Astrophysical Journal, Vol. 383
  • DOI: 10.1086/170831

Phase structure, collective modes, and the axial anomaly in dense QCD
journal, October 2007

Structure of neutron star envelopes
journal, September 1983

  • Gudmundsson, E. H.; Pethick, C. J.; Epstein, R. I.
  • The Astrophysical Journal, Vol. 272
  • DOI: 10.1086/161292

Moment of inertia, quadrupole moment, Love number of neutron star and their relations with strange-matter equations of state
journal, February 2018

  • Bandyopadhyay, Debades; Bhat, Sajad A.; Char, Prasanta
  • The European Physical Journal A, Vol. 54, Issue 2
  • DOI: 10.1140/epja/i2018-12456-y

Are Gravitational Waves Spinning Down PSR J 1023 + 0038 ?
journal, October 2017

Full band all-sky search for periodic gravitational waves in the O1 LIGO data
journal, May 2018

Compact Stars with Sequential QCD Phase Transitions
journal, October 2017

Resonant Shattering of Neutron Star Crusts
journal, January 2012

Constraining the physics of the r-mode instability in neutron stars with X-ray and ultraviolet observations: Constraining the physics of the r-mode instability
journal, June 2012

  • Haskell, Brynmor; Degenaar, Nathalie; Ho, Wynn C. G.
  • Monthly Notices of the Royal Astronomical Society, Vol. 424, Issue 1
  • DOI: 10.1111/j.1365-2966.2012.21171.x

Interface tension and interface entropy in the 2 + 1 flavor Nambu–Jona-Lasinio model
journal, April 2014

Probing dense matter in compact star cores with radio pulsar data
journal, November 2014

Gravitational Waves from F-modes Excited by the Inspiral of Highly Eccentric Neutron Star Binaries
journal, March 2017

  • Chirenti, Cecilia; Gold, Roman; Miller, M. Coleman
  • The Astrophysical Journal, Vol. 837, Issue 1
  • DOI: 10.3847/1538-4357/aa5ebb

Are Small Radii of Compact Stars Ruled out by GW170817/AT2017gfo?
journal, June 2018

Hybrid Stars that Masquerade as Neutron Stars
journal, August 2005

  • Alford, Mark; Braby, Matt; Paris, Mark
  • The Astrophysical Journal, Vol. 629, Issue 2
  • DOI: 10.1086/430902

Critical examination of constraints on the equation of state of dense matter obtained from GW170817
journal, October 2018

Breakdown of i -Love- q Universality in Rapidly Rotating Relativistic Stars
journal, December 2013

  • Doneva, Daniela D.; Yazadjiev, Stoytcho S.; Stergioulas, Nikolaos
  • The Astrophysical Journal, Vol. 781, Issue 1
  • DOI: 10.1088/2041-8205/781/1/L6

Neutron Star Cooling
journal, September 2004

Generic conditions for stable hybrid stars
journal, October 2013

Tidal deformability with sharp phase transitions in binary neutron stars
journal, April 2019

Neutron star collapse and gravitational waves with a non-convex equation of state
journal, January 2019

  • Aloy, Miguel A.; Ibáñez, José M.; Sanchis-Gual, Nicolas
  • Monthly Notices of the Royal Astronomical Society, Vol. 484, Issue 4
  • DOI: 10.1093/mnras/stz293

Covariant representations of the relativistic Brueckner T-matrix and the nuclear matter problem
journal, March 1999

Maximum elastic deformations of relativistic stars
journal, August 2013

    Works referencing / citing this record:

    Treating quarks within neutron stars
    journal, November 2019

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