Observational constraints on hyperons in neutron stars
Top Cited Papers
- 23 January 2006
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review D
- Vol. 73 (2), 024021
- https://doi.org/10.1103/physrevd.73.024021
Abstract
The possibility that neutron stars may contain substantial hyperon populations has important implications for neutron-star cooling and, through bulk viscosity, the viability of the -modes of accreting neutron stars as sources of persistent gravitational waves. In conjunction with laboratory measurements of hypernuclei, astronomical observations were used by Glendenning and Moszkowski [Phys. Rev. Lett. 67, 2414 (1991)] to constrain the properties of hyperonic equations of state within the framework of relativistic mean-field theory. We revisit the problem, incorporating recent measurements of high neutron-star masses and a gravitational redshift. We find that only the stiffest of the relativistic hyperonic equations of state commonly used in the literature is compatible with the redshift. However, it is possible to construct stiffer equations of state within the same framework which produce the observed redshift while satisfying the experimental constraints on hypernuclei, and we do this. The stiffness parameter that most affects the redshift is not the incompressibility but rather the hyperon coupling. Nonrelativistic potential-based equations of state with hyperons are not constrained by the redshift, primarily due to a smaller stellar radius.
Keywords
Other Versions
This publication has 21 references indexed in Scilit:
- Twenty-One Millisecond Pulsars in Terzan 5 Using the Green Bank TelescopeScience, 2005
- Neutron Star CoolingAnnual Review of Astronomy and Astrophysics, 2004
- Discovery of the Neutron Star Spin Frequency in EXO 0748-676The Astrophysical Journal, 2004
- Effect of hyperon bulk viscosity on neutron-starr-modesPhysical Review D, 2002
- Bulk viscosity in superfluid neutron star coresAstronomy & Astrophysics, 2002
- The mass of the neutron star in Vela X-1Astronomy & Astrophysics, 2001
- Neutron Star Mass Measurements. I. Radio PulsarsThe Astrophysical Journal, 1999
- A Millisecond Pulsar in a 6 Hour Orbit: PSR J0751+1807The Astrophysical Journal, 1995
- Determining the nuclear equation of state from neutron-star masses and radiiThe Astrophysical Journal, 1992
- Reconciliation of neutron-star masses and binding of the Λ in hypernucleiPhysical Review Letters, 1991