Spin-orbit precession along eccentric orbits: Improving the knowledge of self-force corrections and of their effective-one-body counterparts (original) (raw)

Linear-in-mass-ratio contribution to spin precession and tidal invariants in Schwarzschild spacetime at very high post-Newtonian order

Physical Review D, 2015

Using black hole perturbation theory and arbitrary-precision computer algebra, we obtain the post-Newtonian (pN) expansions of the linear-in-mass-ratio corrections to the spin-precession angle and tidal invariants for a particle in circular orbit around a Schwarzschild black hole. We extract coefficients up to 20pN order from numerical results that are calculated with an accuracy greater than 1 part in 10 500. These results can be used to calibrate parameters in effective-one-body models of compact binaries, specifically the spin-orbit part of the effective Hamiltonian and the dynamically significant tidal part of the main radial potential of the effective metric. Our calculations are performed in a radiation gauge, which is known to be singular away from the particle. To overcome this irregularity, we define suitable Detweiler-Whiting singular and regular fields in this gauge, and we compute the invariants using mode-sum regularization in combination with averaging from two sides of the particle. The detailed justification of this regularization procedure will be presented in a forthcoming companion paper.

Spin precession in the Schwarzschild spacetime: circular orbits

Classical and Quantum Gravity, 2005

We study the behavior of nonzero rest mass spinning test particles moving along circular orbits in the Schwarzschild spacetime in the case in which the components of the spin tensor are allowed to vary along the orbit, generalizing some previous work.

On gravitomagnetic precession around black holes

Monthly Notices of the Royal Astronomical Society, 1999

We compute exactly the frequency of Lense-Thirring precession for point masses in the Kerr metric, for arbitrary black hole mass and specific angular momentum. We show that this frequency, for point masses at or close to the innermost stable orbit, and for holes with moderate to extreme rotation, is less than, but comparable to the rotation frequency. Thus, if the quasi-periodic oscillations observed in the modulation of the Xray flux from some black holes candidates, BHCs, are due to Lense-Thirring precession of orbiting material, we predict that a separate, distinct QPO ought to be observed in each object.

Geodetic Precession of the Spin in a Non-Singular Gravitational Potential

Using a non-singular gravitational potential which appears in the literature we analytically derived and investigated the equations describing the precession of a body’s spin orbiting around a main spherical body of mass M. The calculation has been performed using a non-exact Schwarzschild solution, and further assuming that the gravitational field of the Earth is more than that of a rotating mass. General theory of relativity predicts that the direction of the gyroscope will change at a rate of 6.6 arcsec/year for a gyroscope in a 650 km high polar orbit. In our case a precession rate of the spin of a very similar magnitude to that predicted by general relativity was calculated resulting to a Sgeo/Sgeo =-5.570^10^-2.

Inspiral of generic black hole binaries: spin, precession and eccentricity

2011

Given the absence of observations of black hole binaries, it is critical that the full range of accessible parameter space be explored in anticipation of future observation with gravitational wave detectors. To this end, we compile the Hamiltonian equations of motion describing the conservative dynamics of the most general black hole binaries and incorporate an effective treatment of dissipation through gravitational radiation, as computed by Will and collaborators. We evolve these equations for systems with orbital eccentricity and precessing spins. We find that, while spinspin coupling corrections can destroy constant radius orbits in principle, the effect is so small that orbits will reliably tend to quasi-spherical orbits as angular momentum and energy are lost to gravitational radiation. Still, binaries that are initially highly eccentric may retain eccentricity as they pass into the detectable bandwidth of ground-based gravitational wave detectors. We also show that a useful set of natural frequencies for an orbit demonstrating both spin precession and periastron precession is comprised of (1) the frequency of angular motion in the orbital plane, (2) the frequency of the plane precession, and (3) the frequency of radial oscillations. These three natural harmonics shape the observed waveform.

Gyroscope precession along unbound equatorial plane orbits around a Kerr black hole

Physical Review D

The precession of a test gyroscope along unbound equatorial plane geodesic orbits around a Kerr black hole is analyzed with respect to a static reference frame whose axes point towards the "fixed stars." The accumulated precession angle after a complete scattering process is evaluated and compared with the corresponding change in the orbital angle. Limiting results for the non-rotating Schwarzschild black hole case are also discussed.

Orbital evolution of a test particle around a black hole. II. Comparison of contributions of spin-orbit coupling and the self-force

Physical review, 2004

We consider the evolution of the orbit of a spinning compact object in a quasi-circular, planar orbit around a Schwarzschild black hole in the extreme mass ratio limit. We compare the contributions to the orbital evolution of both spin-orbit coupling and the local self force. Making assumptions on the behavior of the forces, we suggest that the decay of the orbit is dominated by radiation reaction, and that the conservative effect is typically dominated by the spin force. We propose that a reasonable approximation for the gravitational waveform can be obtained by ignoring the local self force, for adjusted values of the parameters of the system. We argue that this approximation will only introduce small errors in the astronomical determination of these parameters.

Analysis of spin precession in binary black hole systems including quadrupole-monopole interaction

Physical Review D, 2008

We analyze in detail the spin precession equations in binary black hole systems, when the tidal torque on a Kerr black hole due to quadrupole-monopole coupling is taken into account. We show that completing the precession equations with this term reveals the existence of a conserved quantity at 2PN order when averaging over orbital motion. This quantity allows one to solve the (orbitaveraged) precession equations exactly in the case of equal masses and arbitrary spins, neglecting radiation reaction. For unequal masses, an exact solution does not exist in closed form, but we are still able to derive accurate approximate analytic solutions. We also show how to incorporate radiation reaction effects into our analytic solutions adiabatically, and compare the results to solutions obtained numerically. For various configurations of the binary, the relative difference in the accumulated orbital phase computed using our analytic solutions versus a full numerical solution vary from ∼ 0.3% to ∼ 1.8% over ∼ 80 − 140 orbital cycles accumulated while sweeping over the orbital frequency range ∼ 20 − 300 Hz. This typically corresponds to a discrepancy of order ∼ 5 − 6 radians. While this may not be accurate enough for implementation in LIGO template banks, we still believe that our new solutions are potentially quite useful for comparing numerical relativity simulations of spinning binary black hole systems with post-Newtonian theory. They can also be used to gain more understanding of precession effects, with potential application to the gravitational recoil problem, and to provide semi-analytical templates for spinning, precessing binaries.

Analytic self-force calculations in the post-Newtonian regime: Eccentric orbits on a Schwarzschild background

Physical Review D, 2016

We present a method for solving the first-order Einstein field equations in a post-Newtonian (PN) expansion. Our calculations generalize work of Bini and Damour and subsequently Kavanagh et al., to consider eccentric orbits on a Schwarzschild background. We derive expressions for the retarded metric perturbation at the location of the particle for all-modes. We find that, despite first appearances, the Regge-Wheeler gauge metric perturbation is C 0 at the particle for all. As a first use of our solutions, we compute the gauge-invariant quantity U through 4PN while simultaneously expanding in eccentricity through e 10. By anticipating the e → 1 singular behavior at each PN order, we greatly improve the accuracy of our results for large e. We use U to find 4PN contributions to the effective one body potentialQ through e 10 and at linear order in the mass-ratio.

High-order post-Newtonian fit of the gravitational self-force for circular orbits in the Schwarzschild geometry

Physical Review D, 2010

We continue a previous work on the comparison between the post-Newtonian (PN) approximation and the gravitational self-force (SF) analysis of circular orbits in a Schwarzschild background. We show that the numerical SF data contain physical information corresponding to extremely high PN approximations. We find that knowing analytically determined appropriate PN parameters helps tremendously in allowing the numerical data to be used to obtain higher order PN coefficients. Using standard PN theory we compute analytically the leading 4PN and the next-to-leading 5PN logarithmic terms in the conservative part of the dynamics of a compact binary system. The numerical perturbative SF results support well the analytic PN calculations through first order in the mass ratio, and are used to accurately measure the 4PN and 5PN non-logarithmic coefficients in a particular gauge invariant observable. Furthermore we are able to give estimates of higher order contributions up to the 7PN level. We also confirm with high precision the value of the 3PN coefficient. This interplay between PN and SF efforts is important for the synthesis of template waveforms of extreme mass ratio inspirals to be analysed by the space-based gravitational wave instrument LISA. Our work will also have an impact on efforts that combine numerical results in a quantitative analytical framework so as to generate complete inspiral waveforms for the groundbased detection of gravitational waves by instruments such as LIGO and Virgo.