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Papers by Mohammed Qusailah

Research paper thumbnail of Analytic approximations and perturbation methodsand their applications

The paper summarizes the parallel session B3 analytic approximations, perturbation methods and th... more The paper summarizes the parallel session B3 analytic approximations, perturbation methods and their applications of the GR18 conference. The talks in the session reported notably recent advances in black hole perturbations and post-Newtonian approximations as applied to sources of gravitational waves

Research paper thumbnail of Gravitational Recoil of Inspiraling Black Hole Binaries to Second Post‐Newtonian Order

The Astrophysical Journal, 2005

The loss of linear momentum by gravitational radiation and the resulting gravitational recoil of ... more The loss of linear momentum by gravitational radiation and the resulting gravitational recoil of black-hole binary systems may play an important role in the growth of massive black holes in early galaxies. We calculate the gravitational recoil of nonspinning black-hole binaries at the second post-Newtonian order (2PN) beyond the dominant effect, obtaining, for the first time, the 1.5PN correction term due to tails of waves and the next 2PN term. We find that the maximum value of the net recoil experienced by the binary due to the inspiral phase up to the innermost stable circular orbit (ISCO) is of the order of 22 km s −1. We then estimate the kick velocity accumulated during the plunge from the ISCO up to the horizon by integrating the momentum flux using the 2PN formula along a plunge geodesic of the Schwarzschild metric. We find that the contribution of the plunge dominates over that of the inspiral. For a mass ratio m 2 /m 1 = 1/8, we estimate a total recoil velocity (due to both adiabatic and plunge phases) of 100 ± 20 km s −1. For a ratio 0.38, the recoil is maximum and we estimate it to be 250 ± 50 km s −1. In the limit of small mass ratio, we estimate V /c ≈ 0.043 (1 ± 20%) (m 2 /m 1) 2. Our estimates are consistent with, but span a substantially narrower range than, those of Favata et al. (2004).

Research paper thumbnail of Inspiralling compact binaries in quasi-elliptical orbits: The complete third post-Newtonian energy flux

Physical Review D, 2008

The instantaneous contributions to the third post-Newtonian (3PN) gravitational wave luminosity f... more The instantaneous contributions to the third post-Newtonian (3PN) gravitational wave luminosity from the inspiral phase of a binary system of compact objects moving in a quasi elliptical orbit is computed using the multipolar post-Minkowskian wave generation formalism. The necessary inputs for this calculation include the 3PN accurate mass quadrupole moment for general orbits and the mass octupole and current quadrupole moments at 2PN. Using the recently obtained 3PN quasi-Keplerian representation of elliptical orbits the flux is averaged over the binary's orbit. Supplementing this by the important hereditary contributions arising from tails, tails-of-tails and tails squared terms calculated in a previous paper, the complete 3PN energy flux is obtained. The final result presented in this paper would be needed for the construction of ready-to-use templates for binaries moving on non-circular orbits, a plausible class of sources not only for the space based detectors like LISA but also for the ground based ones.

Research paper thumbnail of Tail effects in the third post-Newtonian gravitational wave energy flux of compact binaries in quasi-elliptical orbits

Physical Review D, 2008

The far-zone flux of energy contains hereditary (tail) contributions that depend on the entire pa... more The far-zone flux of energy contains hereditary (tail) contributions that depend on the entire past history of the source. Using the multipolar post-Minkowskian wave generation formalism, we propose and implement a semi-analytical method in the frequency domain to compute these contributions from the inspiral phase of a binary system of compact objects moving in quasi-elliptical orbits up to third post-Newtonian (3PN) order. The method explicitly uses the quasi-Keplerian representation of elliptical orbits at 1PN order and exploits the doubly periodic nature of the motion to average the 3PN fluxes over the binary's orbit. Together with the instantaneous (non-tail) contributions evaluated in a companion paper, it provides crucial inputs for the construction of ready-to-use templates for compact binaries moving on quasi-elliptic orbits, an interesting class of sources for the ground based gravitational wave detectors such as LIGO and Virgo as well as space based detectors like LISA.

Research paper thumbnail of Probing the nonlinear structure of general relativity with black hole binaries

Physical Review D, 2006

Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Spac... more Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Space Antenna (LISA) and stellar mass binary black holes in the European Gravitational Wave Observatory (EGO) offer an unique opportunity to test the nonlinear structure of general relativity. For a binary composed of two nonspinning black holes, the nonlinear general relativistic effects depend only on the masses of the constituents. In a recent paper, we explored the possibility of a test to determine all the post-Newtonian coefficients in the gravitational wave phasing. However, mutual covariances dilute the effectiveness of such a test. In this paper, we propose a more powerful test in which the various post-Newtonian coefficients in the gravitational wave phasing are systematically measured by treating three of them as independent parameters and demanding their mutual consistency. LISA (EGO) will observe BBH inspirals with a signal-to-noise ratio of more than 1000 (100) and thereby test the self-consistency of each of the nine post-Newtonian coefficients that have so-far been computed, by measuring the lower order coefficients to a relative accuracy of 10 ÿ5 (respectively, 10 ÿ4) and the higher order coefficients to a relative accuracy in the range 10 ÿ4 ÿ 0:1 (respectively, 10 ÿ3 ÿ 1).

Research paper thumbnail of Testing post-Newtonian theory with gravitational wave observations

Classical and Quantum Gravity, 2006

The Laser Interferometric Space Antenna (LISA) will observe supermassive black hole binary merger... more The Laser Interferometric Space Antenna (LISA) will observe supermassive black hole binary mergers with amplitude signal-to-noise ratio of several thousands. We investigate the extent to which such observations afford high-precision tests of Einstein's gravity. We show that LISA provides a unique opportunity to probe the non-linear structure of post-Newtonian theory both in the context of general relativity and its alternatives.

Research paper thumbnail of The 2.5PN gravitational wave polarizations from inspiralling compact binaries in circular orbits

Classical and Quantum Gravity, 2004

Using the multipolar post-Minkowskian and matching formalism we compute the gravitational wavefor... more Using the multipolar post-Minkowskian and matching formalism we compute the gravitational waveform of inspiralling compact binaries moving in quasi-circular orbits at the second and a half post-Newtonian (2.5PN) approximation to general relativity. The inputs we use include notably the mass-type quadrupole at the 2.5PN order, the mass octupole and current quadrupole at the 2PN order, the mass 2 5-pole and current 2 4-pole at 1PN. The non-linear hereditary terms come from the monopole-quadrupole multipole interactions or tails, present at the 1.5PN, 2PN and 2.5PN orders, and the quadrupole-quadrupole interaction arising at the 2.5PN level. In particular, the specific effect of non-linear memory is computed using a simplified model of binary evolution in the past. The "plus" and "cross" wave polarisations at the 2.5PN order are obtained in ready-to-use form, extending the 2PN results calculated earlier by Blanchet, Iyer, Will and Wiseman.

Research paper thumbnail of Summary of session B3: analytic approximations, perturbation methods and their applications

Classical and Quantum Gravity, 2008

The paper summarizes the parallel session B3 Analytic approximations, perturbation methods, and t... more The paper summarizes the parallel session B3 Analytic approximations, perturbation methods, and their applications of the GR18 conference. The talks in the session reported notably recent advances in black hole perturbations and post-Newtonian approximations as applied to sources of gravitational waves.

Research paper thumbnail of Generation of gravitational waves from inspiralling compact binaries: 3PN luminosity, 2PN linear momentum flux and applications

This is to certify that the thesis entitled Generation of Gravitational Waves from Inspiralling C... more This is to certify that the thesis entitled Generation of Gravitational Waves from Inspiralling Compact Binaries: 3PN Luminosity, 2PN Linear Momentum Flux and Applications submitted by Mohammed Saleh Saleh Qusailah for the award of the segree of Doctor of Philosophy of Jawaharlal Nehru University is his original work. This has not been published or submitted to any other University for any other Degree or Diploma.

Research paper thumbnail of Analytic approximations and perturbation methodsand their applications

The paper summarizes the parallel session B3 analytic approximations, perturbation methods and th... more The paper summarizes the parallel session B3 analytic approximations, perturbation methods and their applications of the GR18 conference. The talks in the session reported notably recent advances in black hole perturbations and post-Newtonian approximations as applied to sources of gravitational waves

Research paper thumbnail of Gravitational Recoil of Inspiraling Black Hole Binaries to Second Post‐Newtonian Order

The Astrophysical Journal, 2005

The loss of linear momentum by gravitational radiation and the resulting gravitational recoil of ... more The loss of linear momentum by gravitational radiation and the resulting gravitational recoil of black-hole binary systems may play an important role in the growth of massive black holes in early galaxies. We calculate the gravitational recoil of nonspinning black-hole binaries at the second post-Newtonian order (2PN) beyond the dominant effect, obtaining, for the first time, the 1.5PN correction term due to tails of waves and the next 2PN term. We find that the maximum value of the net recoil experienced by the binary due to the inspiral phase up to the innermost stable circular orbit (ISCO) is of the order of 22 km s −1. We then estimate the kick velocity accumulated during the plunge from the ISCO up to the horizon by integrating the momentum flux using the 2PN formula along a plunge geodesic of the Schwarzschild metric. We find that the contribution of the plunge dominates over that of the inspiral. For a mass ratio m 2 /m 1 = 1/8, we estimate a total recoil velocity (due to both adiabatic and plunge phases) of 100 ± 20 km s −1. For a ratio 0.38, the recoil is maximum and we estimate it to be 250 ± 50 km s −1. In the limit of small mass ratio, we estimate V /c ≈ 0.043 (1 ± 20%) (m 2 /m 1) 2. Our estimates are consistent with, but span a substantially narrower range than, those of Favata et al. (2004).

Research paper thumbnail of Inspiralling compact binaries in quasi-elliptical orbits: The complete third post-Newtonian energy flux

Physical Review D, 2008

The instantaneous contributions to the third post-Newtonian (3PN) gravitational wave luminosity f... more The instantaneous contributions to the third post-Newtonian (3PN) gravitational wave luminosity from the inspiral phase of a binary system of compact objects moving in a quasi elliptical orbit is computed using the multipolar post-Minkowskian wave generation formalism. The necessary inputs for this calculation include the 3PN accurate mass quadrupole moment for general orbits and the mass octupole and current quadrupole moments at 2PN. Using the recently obtained 3PN quasi-Keplerian representation of elliptical orbits the flux is averaged over the binary's orbit. Supplementing this by the important hereditary contributions arising from tails, tails-of-tails and tails squared terms calculated in a previous paper, the complete 3PN energy flux is obtained. The final result presented in this paper would be needed for the construction of ready-to-use templates for binaries moving on non-circular orbits, a plausible class of sources not only for the space based detectors like LISA but also for the ground based ones.

Research paper thumbnail of Tail effects in the third post-Newtonian gravitational wave energy flux of compact binaries in quasi-elliptical orbits

Physical Review D, 2008

The far-zone flux of energy contains hereditary (tail) contributions that depend on the entire pa... more The far-zone flux of energy contains hereditary (tail) contributions that depend on the entire past history of the source. Using the multipolar post-Minkowskian wave generation formalism, we propose and implement a semi-analytical method in the frequency domain to compute these contributions from the inspiral phase of a binary system of compact objects moving in quasi-elliptical orbits up to third post-Newtonian (3PN) order. The method explicitly uses the quasi-Keplerian representation of elliptical orbits at 1PN order and exploits the doubly periodic nature of the motion to average the 3PN fluxes over the binary's orbit. Together with the instantaneous (non-tail) contributions evaluated in a companion paper, it provides crucial inputs for the construction of ready-to-use templates for compact binaries moving on quasi-elliptic orbits, an interesting class of sources for the ground based gravitational wave detectors such as LIGO and Virgo as well as space based detectors like LISA.

Research paper thumbnail of Probing the nonlinear structure of general relativity with black hole binaries

Physical Review D, 2006

Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Spac... more Observations of the inspiral of massive binary black holes (BBH) in the Laser Interferometer Space Antenna (LISA) and stellar mass binary black holes in the European Gravitational Wave Observatory (EGO) offer an unique opportunity to test the nonlinear structure of general relativity. For a binary composed of two nonspinning black holes, the nonlinear general relativistic effects depend only on the masses of the constituents. In a recent paper, we explored the possibility of a test to determine all the post-Newtonian coefficients in the gravitational wave phasing. However, mutual covariances dilute the effectiveness of such a test. In this paper, we propose a more powerful test in which the various post-Newtonian coefficients in the gravitational wave phasing are systematically measured by treating three of them as independent parameters and demanding their mutual consistency. LISA (EGO) will observe BBH inspirals with a signal-to-noise ratio of more than 1000 (100) and thereby test the self-consistency of each of the nine post-Newtonian coefficients that have so-far been computed, by measuring the lower order coefficients to a relative accuracy of 10 ÿ5 (respectively, 10 ÿ4) and the higher order coefficients to a relative accuracy in the range 10 ÿ4 ÿ 0:1 (respectively, 10 ÿ3 ÿ 1).

Research paper thumbnail of Testing post-Newtonian theory with gravitational wave observations

Classical and Quantum Gravity, 2006

The Laser Interferometric Space Antenna (LISA) will observe supermassive black hole binary merger... more The Laser Interferometric Space Antenna (LISA) will observe supermassive black hole binary mergers with amplitude signal-to-noise ratio of several thousands. We investigate the extent to which such observations afford high-precision tests of Einstein's gravity. We show that LISA provides a unique opportunity to probe the non-linear structure of post-Newtonian theory both in the context of general relativity and its alternatives.

Research paper thumbnail of The 2.5PN gravitational wave polarizations from inspiralling compact binaries in circular orbits

Classical and Quantum Gravity, 2004

Using the multipolar post-Minkowskian and matching formalism we compute the gravitational wavefor... more Using the multipolar post-Minkowskian and matching formalism we compute the gravitational waveform of inspiralling compact binaries moving in quasi-circular orbits at the second and a half post-Newtonian (2.5PN) approximation to general relativity. The inputs we use include notably the mass-type quadrupole at the 2.5PN order, the mass octupole and current quadrupole at the 2PN order, the mass 2 5-pole and current 2 4-pole at 1PN. The non-linear hereditary terms come from the monopole-quadrupole multipole interactions or tails, present at the 1.5PN, 2PN and 2.5PN orders, and the quadrupole-quadrupole interaction arising at the 2.5PN level. In particular, the specific effect of non-linear memory is computed using a simplified model of binary evolution in the past. The "plus" and "cross" wave polarisations at the 2.5PN order are obtained in ready-to-use form, extending the 2PN results calculated earlier by Blanchet, Iyer, Will and Wiseman.

Research paper thumbnail of Summary of session B3: analytic approximations, perturbation methods and their applications

Classical and Quantum Gravity, 2008

The paper summarizes the parallel session B3 Analytic approximations, perturbation methods, and t... more The paper summarizes the parallel session B3 Analytic approximations, perturbation methods, and their applications of the GR18 conference. The talks in the session reported notably recent advances in black hole perturbations and post-Newtonian approximations as applied to sources of gravitational waves.

Research paper thumbnail of Generation of gravitational waves from inspiralling compact binaries: 3PN luminosity, 2PN linear momentum flux and applications

This is to certify that the thesis entitled Generation of Gravitational Waves from Inspiralling C... more This is to certify that the thesis entitled Generation of Gravitational Waves from Inspiralling Compact Binaries: 3PN Luminosity, 2PN Linear Momentum Flux and Applications submitted by Mohammed Saleh Saleh Qusailah for the award of the segree of Doctor of Philosophy of Jawaharlal Nehru University is his original work. This has not been published or submitted to any other University for any other Degree or Diploma.