所属领域：
空间引力波探测领域
资源类型：
引力波探测
/ 双星绕转
文献作者：
Morsink, SM; Stergioulas, N; Blattnig, SR
文献发表年份：
1999
文献期刊：
ASTROPHYSICAL JOURNAL
文献摘要：We compute zero-frequency (neutral) quasi-normal f-modes of fully relativistic and rapidly rotating neutron stars using several realistic equations of state (EOSs) for neutron star matter. The zero-frequency modes signal the onset of the gravitational radiation-driven instability. We find that the I = m = 2 (bar) f-mode is unstable for stars with gravitational mass as low as 1.0-1.2 M-., depending on the EOS. For 1.4 M-. neutron stars, the bar mode becomes unstable at 83%-93% of the maximum allowed rotation rate. For a wide range of EOSs, the bar mode becomes unstable at a ratio of rotational to gravitational energies T/W similar to 0.07-0.09 for 1.4 M-. stars, and T/W similar to 0.06 for maximum mass stars. This is to be contrasted with the Newtonian value of TIW similar to 0.14. We construct the following empirical formula for the critical value of T/W for the bar mode, (T/W)(2) =0.115 - 0.048M/M-max(sph), which is insensitive to the EOS to within 4%-6%. This formula yields an estimate for the neutral mode sequence of the bar mode as a function only of the: star's mass M, given the maximum allowed mass M-max(sph), of a nonrotating neutron star. The recent discovery of the fast millisecond pulsar in the supernova remnant N157B supports the suggestion that a fraction of proto-neutron stars are born in a supernova collapse with very large initial angular momentum. If some neutron stars are born in an accretion-induced collapse of a white dwarf, then they will also have very large angular momentum at birth. Thus in a fraction of newly born neutron stars the instability is a promising source of continuous gravitational waves,It could also play a major role in the rotational evolution (through the emission of angular momentum) of merged binary neutron stars if their postmerger angular momentum exceeds the maximum allowed to form a Kerr black hole.
文献类型： Article
文献语种： English
关键词： DRIVEN SECULAR INSTABILITY; NEWTONIAN STELLAR MODELS; GRAVITATIONAL-RADIATION; COWLING APPROXIMATION; OSCILLATIONS; PULSATIONS; EQUILIBRIUM; POLYTROPES; VISCOSITY
文献作者地址： Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA; Max Planck Inst Gravitat Phys, Albert Einstein Inst, D-14473 Potsdam, Germany; Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA
