Download presentation
Presentation is loading. Please wait.
Published byScot Rich Modified over 9 years ago
1
TAMA binary inspiral event search Hideyuki Tagoshi (Osaka Univ., Japan) 3rd TAMA symposium, ICRR, 2/6/2003
2
Coalescing compact binaries Neutron stars Black holes Inspiral phase of coalescing compact binaries are main target because Expected event rate of NS-NS merger: a few within 200Mpc /year Well known waveform, etc. Possibility of MACHO black holes
3
TAMA Binary inspiral search 1.Neutron star binary search 2.TAMA-LISM coincident event search for mass range (onestep search) 3.Lower mass 4.Higher mass
4
Matched filter Detector outputs: : known gravitational waveform (template) : noise. Outputs of matched filter: noise spectrum density signal to noise ratio Matched filtering is the process to find optimal parameters which realize Post-Newtonian approximation
5
Matched filtering analysis t Read data FFT of data Apply transfer function Conversion to stain equivalent data Evaluate noise spectrum near the data 52 sec Event list
6
TAMA events and Galactic event Test signals selection will produce loss of strong S/N events TAMA events
7
Search Result TAMA DT6
8
Log10[Number of events]
9
Upper limit to the Galactic event rate N: Upper limit to the average number of events over certain threshold T: Length of data [hours] : Detection efficiency
10
Galactic event simulation We perform Galactic event simulation to estimate detection efficiency Assume binary neutron stars distribution in our Galaxy Give a time during DT6 Determine mass, position, inclination angle, phase by random numbers Give a test signal into real data Search Make event lists and estimate detection efficiency Mass : distribute uniformly between
11
Galactic event detection efficiency
12
Upper limit to the event rate: Poisson statistics Threshold ( ) Expected number of fake events over threshold : N bg =0.1 Observed number of events over threshold: N obs =0 Assuming Poisson distribution for the number of real/fake events over the threshold, we obtain upper limit to the expected number of real events from N=2.3 (C.L.=90%)
13
Upper limit to the Galactic event rate threshold=16 ( ~ S/N=11) (fake event rate=0.8/year) Efficiency We also obtain upper limit to the average number of events over threshold by standard Poisson statistics analysis N=2.3 (C.L.=90%) Observation time T = 1039 hours c.f. Caltech 40m : 0.5/hour (C.L.=90%) Allen et al. Phys. Rev. Lett. 83, 1498 (1999).
14
TAMA DT7: 2002.8.31 ~ 2002.9.2 Best Sensitivity: DT7 analysis
15
DT7 event lists These results will be used for TAMA-LIGO coincidence analysis. 23.7 hours data
17
Divide frequency region into bins. Test whether the contribution to from each bins agree with that expected from chirp signal chi square
18
[1.09minutes] TAMA DT6 all 8/1 ~ 9/20/2001 Variation of Noise power (1 minute average)
19
LISM DT6 9/3 ~ 9/17/2001 Variation of Noise power (1 minute average) [1.09minutes]
20
Binary inspiral search : one step search (Tagoshi, Tatsumi,Takahashi) TAMA-LISM coincidence (Takahashi,Tagoshi,Tatsumi) two step search (Tagoshi, Tanaka) Binary inspiral search using Wavelet: (Kanda) Continuous wave from known pulsar: (Soida, Ando) Burst wave search: (Ando) Noise veto analysis: (Kanda) Calibration: (Tatsumi, Telada,…) Interferometer online diagnostic: (Ando,…) BH ringdown search, Stochastic background search, etc. will be done. Two new post-docs (Tsunesasa(NAOJ),Nakano(Osaka)) TAMA data analysis activity
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.