skip to main content

Title: BREAKDOWN OF I-LOVE-Q UNIVERSALITY IN RAPIDLY ROTATING RELATIVISTIC STARS

It was shown recently that normalized relations between the moment of inertia (I), the quadrupole moment (Q), and the tidal deformability (Love number) exist and for slowly rotating neutron stars they are almost independent of the equation of state (EOS). We extend the computation of the I-Q relation to models rotating up to the mass-shedding limit and show that the universality of the relations is lost. With increasing rotation rate, the normalized I-Q relation departs significantly from its slow-rotation limit, deviating up to 40% for neutron stars and up to 75% for strange stars. The deviation is also EOS dependent and for a broad set of hadronic and strange matter EOSs the spread due to rotation is comparable to the spread due to the EOS, if one considers sequences with fixed rotational frequency. Still, for a restricted sample of modern realistic EOSs one can parameterize the deviations from universality as a function of rotation only. The previously proposed I-Love-Q relations should thus be used with care, because they lose their universality in astrophysical situations involving compact objects rotating faster than a few hundred Hz.
Authors:
; ;  [1] ;  [2]
  1. Theoretical Astrophysics, Eberhard Karls University of Tübingen, Tübingen 72076 (Germany)
  2. Department of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)
Publication Date:
OSTI Identifier:
22364039
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 781; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CALCULATION METHODS; COMPACTS; COMPARATIVE EVALUATIONS; EQUATIONS OF STATE; GRAVITATION; MASS; MOMENT OF INERTIA; NEUTRON STARS; NEUTRONS; QUADRUPOLE MOMENTS; RELATIVISTIC RANGE; ROTATION