Searcharxiv⌕ Search

arXiv · gr-qc/0404029

IIR Adaptive Filters for Detection of Gravitational Waves from Coalescing Binaries

Abstract

In this paper we propose a new strategy for gravitational waves detection from coalescing binaries, using IIR Adaptive Line Enhancer (ALE) filters. This strategy is a classical hierarchical strategy in which the ALE filters have the role of triggers, used to select data chunks which may contain gravitational events, to be further analyzed with more refined optimal techniques, like the the classical Matched Filter Technique. After a direct comparison of the performances of ALE filters with the Wiener-Komolgoroff optimum filters (matched filters), necessary to discuss their performance and to evaluate the statistical limitation in their use as triggers, we performed a series of tests, demonstrating that these filters are quite promising both for the relatively small computational power needed and for the robustness of the algorithms used. The performed tests have shown a weak point of ALE filters, that we fixed by introducing a further strategy, based on a dynamic bank of ALE filters, running simultaneously, but started after fixed delay times. The results of this global trigger strategy seems to be very promising, and can be already used in the present interferometers, since it has the great advantage of requiring a quite small computational power and can easily run in real-time, in parallel with other data analysis algorithms.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

F. Acernese, F. Barone, R. De Rosa, A. Eleuteri, L. Giordano, L. Milano. 2004-06-15. IIR Adaptive Filters for Detection of Gravitational Waves from Coalescing Binaries. https://doi.org/10.1117/12.553016

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Photon propagation and black hole imaging in Kruglov nonlinear electrodynamics

Nonlinear electrodynamics (NLED) modifies photon propagation through an effective optical geometry, allowing optical phenomena to deviate from those predicted solely by the underlying spacetime metric. In this work, we revisit the Kruglov model, which generalizes Born--Infeld electrodynamics, and investigate the corresponding null geodesics in theeffective geometry through direct numerical integration, without relying on strong-field analytical approximations. We analyze the resulting photon spheres, gravitational lensing, black-hole shadows, and thin accretion-disk images, together with their dependence on the parameter $q$. For sufficiently small positive $q$, the effective angular metric develops a pole that generates stable photon orbits outside the event horizon and locally reverses the azimuthal evolution of photon trajectories, producing a distinctive bending pattern that resembles, although does not originate from, frame dragging. Conversely, negative $q$ introduces a zero of the effective correction factor, which acts as a turning point for photon trajectories and prevents them from entering the region where the background metric becomes complex. It produces measurable changes in light deflection, shadow radius, photon-ring morphology, and relativistic images. In particular, smaller positive values of $q$ produce thinner photon rings and enlarged shadow radii, whereas negative values generally lead to broader photon rings and smaller shadows. Comparison with the current Event Horizon Telescope constraints on Sgr~A* shows that a substantial region of the Kruglov parameter space remains compatible with present observations.

gr-qc↗

Parity-dependent wave absorption and optical characteristics of a cored magnetic black hole

We study light propagation and coupled gravitational--electromagnetic waves around a black hole supported by a nonlinear magnetic field. The same field action fixes the geometry, the mass--charge relation, and the wave potentials. We calculate two critical impact parameters for light and solve the coupled scattering equations in both parity sectors. In eight solutions of one action, the two optical scales differ by $3.6$--$7.2\%$. The wave absorption also depends on parity. For $\ell=2$, the gap between the larger absorption eigenvalues reaches about $9.0$ percentage points. A wider frequency scan reveals a stronger effect in the second eigenchannel. The difference between the two absorption traces reaches $24.3$ percentage points. The trace equals twice the absorption of an equal incoherent mixture of incoming gravitational and electromagnetic fields. A controlled test of the wave operator shows that the nonlinear electromagnetic factor $κ$ plays an important role in the parity gap. We also examine four $\ell=3$ cases and use charge-matched Reissner--Nordström black holes as a separate control. The optical and wave calculations provide two complementary properties of the same magnetic source.

gr-qc↗

Perturbative dynamics and relativistic effects of a dyonic Kalb-Ramond black hole

We investigate perturbative dynamics, tidal effects, and relativistic frequency shifts in a dyonic Kalb-Ramond black hole generated by a Lorentz-violating antisymmetric tensor background. The geometry is controlled by the mass $M$, the electric charge $Q$, the magnetic charge $p$, and the Lorentz-violating parameter $\ell$, with the dyonic sector entering through the effective combination $P_{\ell}^{2}=Q^{2}/(1-\ell)^{2}+p^{2}/(1-2\ell)$. First, we analyze the gravitational Doppler effect for radial signal exchange between freely falling and static observers, showing how the dyonic charges weaken the redshift by shifting the frequency ratio toward unity. We then compute the radial and angular tidal forces in a freely falling frame and determine the characteristic radii at which the usual stretching and compression patterns are reversed. The gravitational time delay is also evaluated for null trajectories, showing that the electric and magnetic sectors reduce the delay relative to the reference configuration. In the perturbative sector, we study massless scalar, vector, and spinor test fields together with an effective axial metric model, computing sixth-order WKB spectra and independently checking selected modes using the asymptotic iteration method. At fixed mass and charges, increasing the Lorentz-violating parameter raises the tabulated oscillation frequencies and damping rates in the original time coordinate; their interpretation accounts for time normalization and changes in effective parameters. The independent comparisons support the tested higher-multipole fundamental modes. Time-domain evolutions exhibit damped ringdown followed by power-law tails, whose exponents are estimated through fits incorporating finite time corrections and numerical sensitivity checks.

gr-qc↗