Polycrystalline Crusts in Accreting Neutron Stars
Abstract
The crust of accreting neutron stars plays a central role in many different observational phenomena. In these stars, heavy elements produced by H–He burning in the rapid proton capture (rp-) process continually freeze to form new crust. Here, we investigate the expected composition of the solid phase. We first demonstrate using molecular dynamics that two distinct types of chemical separations occur, depending on the composition of the rp-process ashes. We then calculate phase diagrams for three-component mixtures and use them to determine the allowed crust compositions. We show that, for the large range of atomic numbers produced in the rp-process (Z ~ 10–50), the solid that forms has only a small number of available compositions. We conclude that accreting neutron star crusts should be polycrystalline, with domains of distinct composition. Our findings motivate further work on the size of the compositional domains and have implications for crust physics and accreting neutron star phenomenology.
- Authors:
-
- McGill Univ., Montreal, QC (Canada). Dept of Physics
- Indiana Univ., Bloomington, IN (United States)
- Univ. of Toronto, ON (Canada)
- Publication Date:
- Research Org.:
- Indiana Univ., Bloomington, IN (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Nuclear Physics (NP)
- OSTI Identifier:
- 1542026
- Grant/Contract Number:
- FG02-87ER40365; SC0008808
- Resource Type:
- Accepted Manuscript
- Journal Name:
- The Astrophysical Journal (Online)
- Additional Journal Information:
- Journal Name: The Astrophysical Journal (Online); Journal Volume: 860; Journal Issue: 2; Journal ID: ISSN 1538-4357
- Publisher:
- Institute of Physics (IOP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTRONOMY AND ASTROPHYSICS; accretion; accretion disks; dense matter; stars: interiors; stars: neutron; X-rays: binaries; X-rays: bursts
Citation Formats
Caplan, Matthew E., Cumming, Andrew, Berry, D. K., Horowitz, C. J., and Mckinven, R. Polycrystalline Crusts in Accreting Neutron Stars. United States: N. p., 2018.
Web. doi:10.3847/1538-4357/aac2d2.
Caplan, Matthew E., Cumming, Andrew, Berry, D. K., Horowitz, C. J., & Mckinven, R. Polycrystalline Crusts in Accreting Neutron Stars. United States. https://doi.org/10.3847/1538-4357/aac2d2
Caplan, Matthew E., Cumming, Andrew, Berry, D. K., Horowitz, C. J., and Mckinven, R. Thu .
"Polycrystalline Crusts in Accreting Neutron Stars". United States. https://doi.org/10.3847/1538-4357/aac2d2. https://www.osti.gov/servlets/purl/1542026.
@article{osti_1542026,
title = {Polycrystalline Crusts in Accreting Neutron Stars},
author = {Caplan, Matthew E. and Cumming, Andrew and Berry, D. K. and Horowitz, C. J. and Mckinven, R.},
abstractNote = {The crust of accreting neutron stars plays a central role in many different observational phenomena. In these stars, heavy elements produced by H–He burning in the rapid proton capture (rp-) process continually freeze to form new crust. Here, we investigate the expected composition of the solid phase. We first demonstrate using molecular dynamics that two distinct types of chemical separations occur, depending on the composition of the rp-process ashes. We then calculate phase diagrams for three-component mixtures and use them to determine the allowed crust compositions. We show that, for the large range of atomic numbers produced in the rp-process (Z ~ 10–50), the solid that forms has only a small number of available compositions. We conclude that accreting neutron star crusts should be polycrystalline, with domains of distinct composition. Our findings motivate further work on the size of the compositional domains and have implications for crust physics and accreting neutron star phenomenology.},
doi = {10.3847/1538-4357/aac2d2},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 860,
place = {United States},
year = {2018},
month = {6}
}
Web of Science
Works referenced in this record:
Gravitational Radiation and Rotation of Accreting Neutron Stars
journal, July 1998
- Bildsten, Lars
- The Astrophysical Journal, Vol. 501, Issue 1
The Ocean and Crust of a Rapidly Accreting Neutron Star: Implications for Magnetic Field Evolution and Thermonuclear Flashes
journal, April 1998
- Brown, Edward F.; Bildsten, Lars
- The Astrophysical Journal, Vol. 496, Issue 2
Mapping Crustal Heating with the Cooling Light Curves of Quasi-Persistent Transients
journal, May 2009
- Brown, Edward F.; Cumming, Andrew
- The Astrophysical Journal, Vol. 698, Issue 2
Rapid Neutrino Cooling in the Neutron Star MXB 1659-29
journal, April 2018
- Brown, Edward F.; Cumming, Andrew; Fattoyev, Farrukh J.
- Physical Review Letters, Vol. 120, Issue 18
Monte Carlo Study of a One‐Component Plasma. I
journal, September 1966
- Brush, S. G.; Sahlin, H. L.; Teller, E.
- The Journal of Chemical Physics, Vol. 45, Issue 6
Colloquium : Astromaterial science and nuclear pasta
journal, October 2017
- Caplan, M. E.; Horowitz, C. J.
- Reviews of Modern Physics, Vol. 89, Issue 4
Lower limit on the heat capacity of the neutron star core
journal, February 2017
- Cumming, Andrew; Brown, Edward F.; Fattoyev, Farrukh J.
- Physical Review C, Vol. 95, Issue 2
Validity of the linear mixing rule for strongly coupled ionic fluids
journal, October 2003
- DeWitt, H.; Slattery, W.
- Contributions to Plasma Physics, Vol. 43, Issue 56
First-order anharmonic correction to the free energy of a Coulomb crystal in periodic boundary conditions
journal, October 1990
- Dubin, Daniel H. E.
- Physical Review A, Vol. 42, Issue 8
Nuclear composition and heating in accreting neutron-star crusts
journal, June 2003
- Haensel, P.; Zdunik, J. L.
- Astronomy & Astrophysics, Vol. 404, Issue 2
Discovery of a Second Transient Low-Mass X-Ray Binary in the Globular Cluster ngc 6440
journal, April 2010
- Heinke, C. O.; Altamirano, D.; Cohn, H. N.
- The Astrophysical Journal, Vol. 714, Issue 1
Structure of accreted neutron star crust
journal, June 2009
- Horowitz, C. J.; Berry, D. K.
- Physical Review C, Vol. 79, Issue 6
Phase separation in the crust of accreting neutron stars
journal, June 2007
- Horowitz, C. J.; Berry, D. K.; Brown, E. F.
- Physical Review E, Vol. 75, Issue 6
Thermal conductivity and phase separation of the crust of accreting neutron stars
journal, February 2009
- Horowitz, C. J.; Caballero, O. L.; Berry, D. K.
- Physical Review E, Vol. 79, Issue 2
Fusion of neutron-rich oxygen isotopes in the crust of accreting neutron stars
journal, April 2008
- Horowitz, C. J.; Dussan, H.; Berry, D. K.
- Physical Review C, Vol. 77, Issue 4
Direct molecular dynamics simulation of liquid-solid phase equilibria for a three-component plasma
journal, December 2012
- Hughto, J.; Horowitz, C. J.; Schneider, A. S.
- Physical Review E, Vol. 86, Issue 6
Electrical and thermal conductivities of dense matter in the crystalline lattice phase. II - Impurity scattering
journal, February 1993
- Itoh, Naoki; Kohyama, Yasuharu
- The Astrophysical Journal, Vol. 404
Elastic properties of polycrystalline dense matter
journal, March 2015
- Kobyakov, D.; Pethick, C. J.
- Monthly Notices of the Royal Astronomical Society: Letters, Vol. 449, Issue 1
Magnetic Fields of Neutron Stars
journal, September 2017
- Konar, Sushan
- Journal of Astrophysics and Astronomy, Vol. 38, Issue 3
A Survey of Chemical Separation in Accreting Neutron Stars
journal, May 2016
- Mckinven, Ryan; Cumming, Andrew; Medin, Zach
- The Astrophysical Journal, Vol. 823, Issue 2
Crystallization of classical multicomponent plasmas
journal, March 2010
- Medin, Zach; Cumming, Andrew
- Physical Review E, Vol. 81, Issue 3
Equations of state and phase diagrams for dense multi-ionic mixture plasmas
journal, August 1993
- Ogata, Shuji; Iyetomi, Hiroshi; Ichimaru, Setsuo
- Physical Review E, Vol. 48, Issue 2
Equation of state of fully ionized electron-ion plasmas. II. Extension to relativistic densities and to the solid phase
journal, December 2000
- Potekhin, Alexander Y.; Chabrier, Gilles
- Physical Review E, Vol. 62, Issue 6
Nuclear physics in normal X-ray bursts and superblasts
journal, May 2003
- Schatz, Hendrik; Bildsten, Lars; Cumming, Andrew
- Nuclear Physics A, Vol. 718
The Rapid Proton Process Ashes from Stable Nuclear Burning on an Accreting Neutron Star
journal, October 1999
- Schatz, Hendrik; Bildsten, Lars; Cumming, Andrew
- The Astrophysical Journal, Vol. 524, Issue 2
Neutron star cooling after deep crustal heating in the X-ray transient KS 1731-260
journal, November 2007
- Shternin, P. S.; Yakovlev, D. G.; Haensel, P.
- Monthly Notices of the Royal Astronomical Society: Letters, Vol. 382, Issue 1
Bond-orientational order in liquids and glasses
journal, July 1983
- Steinhardt, Paul J.; Nelson, David R.; Ronchetti, Marco
- Physical Review B, Vol. 28, Issue 2
Accretion and evolution of the neutron star magnetic field
journal, August 1995
- Urpin, V.; Geppert, U.
- Monthly Notices of the Royal Astronomical Society, Vol. 275, Issue 4
Melting of icosahedral gold nanoclusters from molecular dynamics simulations
journal, June 2005
- Wang, Yanting; Teitel, S.; Dellago, Christoph
- The Journal of Chemical Physics, Vol. 122, Issue 21
Detecting gravitational wave emission from the known accreting neutron stars
journal, September 2008
- Watts, Anna L.; Krishnan, Badri; Bildsten, Lars
- Monthly Notices of the Royal Astronomical Society, Vol. 389, Issue 2
Fusion reactions in multicomponent dense matter
journal, September 2006
- Yakovlev, D. G.; Gasques, L. R.; Afanasjev, A. V.
- Physical Review C, Vol. 74, Issue 3
Works referencing / citing this record:
Nuclear physics of the outer layers of accreting neutron stars
journal, July 2018
- Meisel, Zach; Deibel, Alex; Keek, Laurens
- Journal of Physics G: Nuclear and Particle Physics, Vol. 45, Issue 9
Breaking properties of neutron star crust
journal, August 2018
- Baiko, D. A.; Chugunov, A. I.
- Monthly Notices of the Royal Astronomical Society, Vol. 480, Issue 4
Elastic properties of binary crystals in neutron stars and white dwarfs
journal, April 2019
- Kozhberov, A. A.
- Monthly Notices of the Royal Astronomical Society, Vol. 486, Issue 4
General Relativistic Surface Degrees of Freedom in Perturbed Hybrid Stars
journal, January 2019
- Pereira, Jonas P.; Lugones, Germán
- The Astrophysical Journal, Vol. 871, Issue 1
Nuclear Physics of the Outer Layers of Accreting Neutron Stars
text, January 2018
- Meisel, Zach; Deibel, Alex; Keek, Laurens
- arXiv
General relativistic surface degrees of freedom in perturbed hybrid stars
text, January 2018
- Pereira, Jonas P.; Lugones, Germán
- arXiv