1. 15-18 Dec 2004Spinning Black Hole Binaries1 Search for Spinning Black Hole Binaries in LIGO/GEO data: The First Steps Speaker: Gareth Jones LSC Inspiral Group GWDAW 9: 15-18/12/2004

2. 15-18 Dec 2004Spinning Black Hole Binaries2 Overview Goal: Detection of Spinning Black Hole Binaries in LIGO/GEO data Matched-filter algorithm within framework of LIGO Algorithm Library (LAL) “BCVSpin” Detection Template Family Testing of filter code Template bank Conclusion

3. 15-18 Dec 2004Spinning Black Hole Binaries3 Post-Newtonian waveforms describes generic GW emission by SBBH using 17 physical parameters: L totalm 1, m 2, L total, s 1, s 2, N, t c, φ c, e Precession of orbital plane modulates GW phase and amplitude Motivation: due to modulations SBBH may be undetectable with existing “filters” used to search for non-spinning BBH’s Too many parameters s1s1 L total Time (s) Strain Without spin With spin s2s2 N Detector m1m1 m2m2

4. 15-18 Dec 2004Spinning Black Hole Binaries4 BCVSpin Template Family Describes generic GW emitted by SBBH using 11 phenomenological parameters ψ 0, ψ 3, β, f final, α 1, α 2, α 3, α 4, α 5, α 6, t c Frequency domain templates Adiabatic-inspiral regime Detection rather than parameter estimation Fitting factor ≥ 0.97 for BH-BH Implemented in LAL as 6 orthonormal filters Buonanno, Chen & Vallisneri, Phys. rev. D 104025, gr-qc 0211087 AmplitudePhase Template bank Maximisation time Strain BCVSpin waveform

5. 15-18 Dec 2004Spinning Black Hole Binaries5 Gaussian white noise –Expect SNR 2 to follow a χ 2 distribution 2 d.o.f. when β = 0 6 d.o.f. when β ≠ 0 –Setting threshold based upon estimated false alarm rate –Different thresholds required for β=0 and β≠0 scenario SNR 2 β ≠ 0, 6 d.o.f Testing the BCVSpin filters β = 0, 2 d.o.f Median estimator for PSD Mean estimator for PSD Expected distribution of SNR 2

6. 15-18 Dec 2004Spinning Black Hole Binaries6 Testing the BCVSpin filters (2) Create “target” BCVSpin waveform with known parameters: ψ 0 =210594, ψ 3 =-1636, β=1000, random choice of α values –~ (5-5) M sol Create a template bank containing a range of equally spaced ψ 0, ψ 3, β values Measure overlap between each template and “target” waveform –Ellipse of ambiguity –Observe the reduction in overlap due to mismatch between template and “target” waveforms parameters time Strain Injected BCVspin waveform

7. 15-18 Dec 2004Spinning Black Hole Binaries7 Peak: Overlap = 1 ΔΨ 3 (template – injected) ΔΨ 0 (template – injected) Red indicates a good match (large overlap value) between the template and injected waveform, blue indicates a poor match Overlap Δβ = -500 ΔΨ 3 (template – injected) Δβ = +500 Δβ = 0 ΔΨ 0 (template – injected)

8. 15-18 Dec 2004Spinning Black Hole Binaries8 Composite map “Maximise” over β Choose highest overlap value for each (ψ 0, ψ 3 ) Ellipse shape Ψ 3 (template – injected) Ψ 0 (template – injected) Overlap

9. 15-18 Dec 2004Spinning Black Hole Binaries9 BCVSpin template bank ψ 0, ψ 3, β, f final Currently we have 3-dimensional template bank (ψ 0, ψ 3, β) for NS- BH m 1 = (1-3)M sol, m 2 = (6-14)M sol M 1 (M solar ) M 2 (M solar ) NS-BH BH-BH 1 3 6 12 14

10. 15-18 Dec 2004Spinning Black Hole Binaries10 BCVSpin template bank (2) 1255 templates (2048s L1) Static metric ψ3ψ3 β β ψ0ψ0 ψ0ψ0 ψ3ψ3 0 400,000 800,000 -5,000 -3,500 -2,000 -2,000 -5,000 600 0 0

11. 15-18 Dec 2004Spinning Black Hole Binaries11 Conclusion BCVSpin filter code for SBBH search ready Template bank for NS-BH currently in use, bank for BH-BH in near future Bank generation and filtering techniques have been tested Beginning to filter S2 data