1. LIGO-G040319-01-Z Status of the LIGO-TAMA Joint Bursts Search Patrick Sutton LIGO Laboratory, Caltech, for the LIGO-TAMA Joint Working Group

2. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/052 Outline l Background l Science with LIGO-TAMA l Analysis Status l Upper Limits from the Playground l Remaining Tasks and Outlook

3. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/053 Un-triggered Bursts Analysis l The LIGO S2 un-triggered search for generic GWBs at high frequencies is being carried out jointly with TAMA. »LIGO-only search: 64-1100Hz »LIGO-TAMA search: 700-2000Hz l Philosophy of LIGO-TAMA: Use machinery and techniques common with the LIGO-only low- frequency search »ETGs, coincidence, r-statistic, time lags, MDC simulation frames, low false rate (<<1/S2), rate vs strength upper limits, … l Seek optimal ways to combine LIGO and TAMA for best science.

4. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/054 LIGO-TAMA in S2/DT8 LIGO and TAMA look with best sensitivity at different frequencies: l Tune for signals near minimum of envelope, [700-2000]Hz. l Complementary to LIGO- only bursts search in [64,1100]Hz. Duty cycles: H174% H258% L137% T181%

5. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/055 Science with TAMA l TAMA-LIGO 4X search has several interesting features: »4X coincidence allows for searches with very low false rates (nanoHz). »Extra time lags allow much more accurate background estimates –LIGO 2-site network = 47 lags in (-115s,+115s) –LIGO-TAMA 3-site network = 47 2 = 2209 lags in (-115s,+115s). »Extra non-aligned site with long baseline: exploit for sky direction? polarization information? (Not yet explored). l But 3X searches also valuable: »Can use TAMA as substitute for a missing LIGO detector. »Eg: H1-H2-T1 coincidence allows us to use the large amount of H1-H2 data that would otherwise be lost because of poor L1 duty cycle (Cadonati, also done in joint inspiral search).

6. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/056 Data Sets l TAMA doubles total usable data set »Better chance of “getting lucky” in a search »Cut rate upper limits in half »Cost: some loss in efficiency (minor effect) l Response: Analyze all H1-H2-(L1 or T1) data »H1-L1-T1, H2-L1-T1: small amount of data, much higher false rate. Ignore. H1-H2-L1-T1250hr H1-H2-  L1-T1 325hr H1-H2-L1-  T1 62hr total LIGO-TAMA637hr total LIGO-only312hr  L1  L1 not operating  T1  T1 not operating

7. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/057 l Event Generation separately by each collaboration: »BlockNormal, Power, TFClusters, WaveBurst for LIGO, Power for TAMA »Single tuning for all data sets: maximize efficiencies while keeping < 1 background event for S2. l Coincidence & Cross-Correlation: »Exchange triggers, look for coincidences in all IFOs operating »Use r-statistic cross-correlation test among LIGO triggers (H1-H2-L1 or H1- H2) to reduce false alarm rate »Time-lag analysis gives false rate. l Efficiencies: »Measure using coordinated signal injections (MDC frames) l Detections/Upper Limits: »Rate of detectable events, rate versus event strength. Analysis Procedure

8. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/058 Playground analysis (10% subset of data): 1.Compute false rate of each ETG & IFO as a function of threshold. 2.Use simulations to tune coincidence parameters (LIGO 3X and LIGO-TAMA) and estimate efficiencies as a function of threshold. 3.Perform coincidence and compute “practice” upper limit. –Modify tuning/thresholds if necessary. Freeze tuning and repeat coincidence, upper limit analysis for full data set. Current Status we are here »Goal: complete by end September

9. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/059 Playground Analysis l Available triggers: »TAMA: Complete sets for raw data with high threshold (SNR>10), complete SG13 simulations (sine-Gaussians) at low threshold. »TFClusters: complete H1-H2 and H1-H2-L1 raw triggers, complete SG13 triggers. »WaveBurst: complete H1-H2-L1 and SG13 triggers. »Power, BlockNormal: Triggers in production. l Since have complete trigger sets for TAMA and TFClusters, use these in playground analysis. »Need to perform full playground analysis with all ETGs before performing coincidence over full data set.

10. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0510 Efficiency vs False Rate From coordinated simulation runs (SG13) Test waveforms: Q=9 sine-Gaussians in [700-2000]Hz (averaged over band). Tune for similar efficiencies. TFClusters-TAMA operating points TAMA TFClusters (3X) WaveBurst (3X)

11. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0511 Measured Network Efficiency Different network combinations have similar efficiency (factor ~2 in 50% point). Will get better statistics from full data set simulations. Preliminary

12. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0512 Upper Limits NetworkNT (s) N bck R 90% ( 1/day )h 50% ( Hz -1/2 ) H1-H2-L1-T10 65963 0.002 3.22.5x10 -19 H1-H2-  L1-T1 0 97806<0.024 2.12.3x10 -19 H1-H2-L1-  T1 0 7971<0.02526.21.2x10 -19 Playground (measured) 0171740<0.051 1.2*2.4x10 -19 Full Data Set (expected) 01.7x10 6 <0.50.12*2.4x10 -19 Including the R-Statistic: * Treating all 3 data sets as one experiment (naïve).

13. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0513 Upper Limits Including the R-Statistic: * Treating all 3 data sets as one experiment (naïve). NetworkNT (s) N bck R 90% ( 1/day )h 50% ( Hz -1/2 ) H1-H2-L1-T10 65963 0.002 3.22.5x10 -19 H1-H2-  L1-T1 0 97806<0.024 2.12.3x10 -19 H1-H2-L1-  T1 0 7971<0.02526.21.2x10 -19 Playground (measured) 0171740<0.051 1.2*2.4x10 -19 Full Data Set (expected) 01.7x10 6 <0.50.12*2.4x10 -19 best efficiency lowest false rate largest livetime

14. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0514 Upper Limits Preliminary

15. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0515 Next Steps l Repeat playground analysis including other LIGO ETGs. »Fix ETG and R-Statistic thresholds. »Limit each ETG to same false rate. l Full data set coincidence, final upper limits. l Other: »May want simulations with more waveforms - only sine-Gaussians so far (processing MDC frames very laborious for TAMA). »Technical point: Feldman-Cousins procedure not trivially extendible to multiple independent experiments with different backgrounds (eg: H1-H2-L1-T1, H1-H2- T1, etc). Need to think carefully about algorithm for computing final upper limits.

16. LIGO-G040319-01-ZSutton LSC Mtg 2004/06/0516 Summary l TAMA-LIGO joint search for GWBs in S2 is in late stages. »High-frequency search complementary to LIGO-only search at low frequencies. l Two parts of search: »4X: very low false rate »3X: lots of additional observation time l Expect rate upper limit ~1/2 that attainable with LIGO-only search. l Current status: »Rapid progress over last two months. »Currently performing playground analysis. »Goal: Complete full analysis by end September, present paper at Nov LSC meeting. l S3?