Gravitational waves from galaxy encounters

Abstract

We discuss the emission of gravitational radiation produced in encounters of dark matter galactic halos. To this aim we perform a number of numerical simulations of typical galaxy mergers, computing the associated gravitational radiation waveforms as well as the energy released in the processes. Our simulations yield dimensionless gravitational wave amplitudes of the order of $10^{-13}$ and gravitational wave frequencies of the order of $10^{-16}$ Hz, when the galaxies are located at a distance of 10 Mpc. These values are of the same order as those arising in the gravitational radiation originated by strong variations of the gravitational field in the early Universe, and therefore, such gravitational waves cannot be directly observed by ground-based detectors. We discuss the feasibility of an indirect detection by means of the B-mode polarization of the Cosmic Microwave Background (CMB) induced by such waves. Our results show that the gravitational waves from encounters of dark matter galactic halos leave much too small an imprint on the CMB polarization to be actually observed with ongoing and future missions.

9 pages with revtex style, 3 ps figures; to be published in Physical Review D

References in corpus (14)

• Using gravitational-wave standard sirens
• Massive Black Hole Binary Evolution
• The influence of gas on the structure of merger remnants
• The gravitational wave signal from massive black hole binaries and its contribution to the LISA data stream
• On the Origin of Isophotal Shapes in Elliptical Galaxies
• Dynamics of galaxy cores and supermassive black holes
• Imprints of Relic Gravitational Waves in Cosmic Microwave Background Radiation
• Elliptical galaxies from mergers of discs
• Encounters between spherical galaxies II: systems with dark halo
• Encounters between spherical galaxies I: systems without dark halo
• The Surprising Anisotropy of Fast Rotating, Disky Elliptical Galaxies
• Stochastic gravitational wave background from cold dark matter halos
• Evolution of polarization orientations in a flat universe with vector perturbations: CMB and quasistellar objects
• Merging of Elliptical Galaxies as Possible Origin of the Intergalactic Stellar Population

Cited by in corpus (4)

• Computing General Relativistic effects from Newtonian N-body simulations: Frame dragging in the post-Friedmann approach
• Stable vortex structures in colliding self-gravitating Bose-Einstein condensates
• Revealing turbulent Dark Matter via merging of self-Gravitating condensates
• Systematic Study of Gravitational Waves from Galaxy Merger