1. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) Results of the search for burst gravitational waves with the TAMA300 detector Masaki Ando (Department of Physics, University of Tokyo) and The TAMA Collaboration

2. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 2 Target of this work … Burst gravitational waves Predicted waveforms of stellar-core collapse TAMA300 data Data Taking 9 Data analysis Excess power filter Fake reduction Galactic simulation Signal injection simulation Introduction Upper limit for Galactic events Galactic event rate GW energy rate

3. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 3 Outline Target waveform TAMA300 data Overview, Observation runs, Noise level Analysis scheme Burst filter, Fake reduction Analysis results Event-trigger rate Galactic simulation Summary and Conclusion

4. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 4 Analysis target - Target waveforms - Targets : Burst waves from stellar-core collapse Common characteristics Short burst waves Spike wave ~1msec Duration time <30msec Not suitable for templates (matched filtering: not available) Numerical simulations … ~100 waveforms are obtained Not cover all initial conditions H.Dimmelmeier et al, Astron. Astrophys. 393 (2002) 523. Amplitude : h rss : 4 x 10 -22 /Hz 1/2 (at Galactic center: 8.5kpc) Energy : E tot : 9 x 10 -8 M o c 2 Reference waveforms Relativistic, axisymmetric simulation by Dimmelmeier et al. 26 waveforms

5. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 5 TAMA300 (1) - Overview - Data : Observation data by TAMA300 National Astronomical Observatory at Mitaka, Japan Baseline 300m TAMA300, an interferometric GW detector in Japan Baseline length : 300m Fabry-Perot-Michelson interferometer with power recycling Placed at National Astronomical Observatory in Japan Sufficient sensitivity for Galactic binary inspirals Automated crewless operation 9 observation runs (Data : ~3000 hours) First obs. run in 1999 (DT1) Upgrade and observation runs

6. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 6 TAMA observation runs TAMA300 (2) - Observation runs - Data TakingObjective Observation time Typical strain noise level Total data (Longest lock) DT1August, 1999Calibration test1 night3x10 -19 /Hz 1/2 10 hours (7.7 hours) DT2 September, 1999 First Observation run3 nights3x10 -20 /Hz 1/2 31 hours DT3April, 2000 Observation with improved sensitivity 3 nights1x10 -20 /Hz 1/2 13 hours DT4 Aug.-Sept., 2000 100 hours' observation data 2 weeks (night-time operation) 1x10 -20 /Hz 1/2 (typical) 167 hours (12.8 hours) DT5March, 2001 100 hours' observation with high duty cycle 1 week (whole-day operation) 1.7x10 -20 /Hz 1/2 (LF improvement) 111 hours DT6 Aug.-Sept., 2001 1000 hours' observation data 50 days5x10 -21 /Hz 1/2 1038 hours (22.0 hours) DT7 Aug.-Sept., 2002 Full operation with Power recycling 2 days25 hours DT8 Feb.-April., 2003 1000 hours Coincidence 2 months3x10 -21 /Hz 1/2 1157 hours (20.5 hours) DT9 Nov. 2003 - Jan., 2004 Automatic operation 6 weeks1.5x10 -21 /Hz 1/2 558 hours (27 hours)

7. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 7 TAMA300 (3) - Data Taking 9 - TAMA DT9 DT9 DT8 DT6 Noise floor level drift Data Taking 9 Nov. 28, 2003 – Jan. 10, 2004 558 hours of data Noise level : 2x10 -21 /Hz 1/2 2 nd half : 200 hours (Christmas, new-year Holiday terms) Better noise level Stable environment This analysis …

8. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 8 TAMA300 (4) - Noise spectrum - Noise spectrum TAMA noise spectrum with Dimmelmeier waveforms Detectable range : ~ 300 pc (optimal direction, polarization)

9. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 9 Burst filter : Excess power filter Burst-wave analysis (1) - Excess power filter - Raw Data (time series) Total power in given T-F region Few assumptions for signal … time-frequency bands Robust for waveform uncertainties Signal !! Evaluate signal power in given time-freqency regions Spectrogram Freq. sum Time- Frequency plane (spectrogram)

10. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 10 Burst-wave analysis (2) - Filter parameters - Filter parameters (time-frequency window)  t = 12.8 [msec]  f = 2300 [Hz] For higher SNR … Short time window ~Signal duration Requires line removal Wide frequency window Limited by worse noise level at low and high freq. Burst GW → Short duration, wide frequency band (c.f. Cont. waves: long duration, narrow freq. band)

11. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 11 Burst-wave analysis (3) - Data conditioning - Data conditioning Line removal Filter freq. resolution : ~80Hz  line removal is required (AC line, Violin mode peak, Calibration peak) Without Line Removal With Line Removal Method FFT 72sec data Reject line freq. components Inverse FFT Normalization Track the drift of noise level  Each spectrum is normalized by averaged noise spectrum Use 30min-averaged spectrum 30min (5.6x10 -4 Hz)

12. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 12 Burst-wave analysis (4) - Fake reduction - Fake reduction, Injection test Veto with monitor channels Burst signal < 100 msec Most detector noises > a few seconds Correlated bursts in intensity monitor channel Effective to long-duration noises Time-scale selection Two veto methods Effective to short spikes Less than 2% Safety check : not to reject real signals Confirm that monitor channel bursts were not caused by real GW signal Hardware and software injections veto threshold Event threshold Hardware injection results DT8 analysis results (before veto) False-dismissal rate estimation Calibration : SNR (filter output)  h rss

13. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 13 TAMA burst analysis - Analysis results - Analysis results Improvement in rates with veto analyses Better in DT9 than DT8 Fake rate : 30 –100 times Sensitivity : 3-6 times Still many fake events Trigger rate with vetoes DT9 DT8 DT6 DT9 (before veto) Much larger than results with Gaussian noise

14. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 14 Galactic simulation (1) - Simulation method - Galactic simulation Monte-Carlo simulation Random events Inject signal to real data Analyze data with same codes Investigate ‘what happens with real signals’  compare with obs. results Position : Somewhere in Galaxy R = (x 2 +y 2 ) 1/2 R d : 3.5 kpc, h d : 325 pc Exponential Disk model Time ： Somewhere in DT9 (200hr) Detector angular depend. Source : 26 Dimmelmeier waveforms Random angle Source angular depend. Effective distance Galactic-event distribution

15. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 15 Galactic simulation (2) - Results - Results of Galactic injection test Event-selection threshold : SNR>2.9 Detection efficiency : 1x10 -5 Observation result : 7x10 -2 events/sec Galactic event rate 6 x 10 –4 M o c 2 /sec GW energy rate 6 x 10 3 events/sec (90% C.L.) Upper limit Assume a Poisson distribution for the observed event number N obs  N ul

16. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 16 Summary Burst-wave analysis with TAMA300 data TAMA300 DT9, 200hours of data Excess Power filter, Fake reduction Galactic event simulation (Simulated-signal injection test) Too large for real events Originate in residual fake triggers Galactic event rate 6 x 10 –4 M o c 2 /sec Galactic GW energy rate 6 x 10 3 events/sec (90% C.L.)

17. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 17 Conclusion Conclusion Current works TAMA detector improvement (Noise hunting, Better isolation) Better filter (Filter tuning, better burst filter) Coincidence analysis (LIGO, ROG) This work … Scheme to set upper limits for Galactic events from observation data We need … More realistic waveform catalog More realistic Galactic model Next-generation detector to cover our Galaxy (Ad-LIGO, LCGT)

18. The 9th Gravitational Wave Data Analysis Workshop (December 15-18, 2004, Annecy, France) 18 End