1. Performance of the WaveBurst algorithm on LIGO S2 playground data
S.Klimenko (UF), I.Yakushin (LLO),
G.Mitselmakher (UF), M.Rakhmanov(UF)
for LIGO collaboration
Introduction
Trigger production
Triple coincidence
Simulation
sine-Gaussian
BH-BH mergers
Summary
S.Klimenko, December 2003, GWDAW 1

2. excess power detection method in wavelet domain
Introduction
WaveBurst (see S.Klimenko’s talk for details)
excess power detection method in wavelet domain
flexible tiling of the TF-plane by using wavelet packets
variety of basis waveforms for burst approximation
local in time & frequency, low spectral leakage
use rank statistics  non-parametric
use local T-F coincidence rules for multiple IFOs
coincidence applied before triggers are produced
works better for 2 and more interferometers (but can do analysis with one interferometer as well)
Symlet 58
Symlet 58 packet (4,7)
S.Klimenko, December 2003, GWDAW 2

3. Wavelet time-scale(frequency) spectrogram
H2:LSC-AS_Q
LIGO data
WaveBurst allows different tiling schemes including
linear and dyadic wavelet scale resolution.
currently linear scale resolution is used (Df=const)
S.Klimenko, December 2003, GWDAW 2

4. WaveBurst pipeline coincidence band 64-4096 Hz bp bp bp
wavelet transform,
data conditioning,
rank statistics
channel 1
IFO1 event
generation bp
wavelet transform,
data conditioning
rank statistics
channel 2,…
IFO2 event
generation bp
coincidence
TF1
TF2
“coincidence”
band Hz
selection cuts: coincidence likelihood>1.5, cluster likelihood>4 bp
 selection of black pixels (10% loudest)
S.Klimenko, December 2003, GWDAW 2

5. Raw Coincidence Rates off-time samples are produced during
ifo pair
L1-H1
H1-H2
H2-L1
triggers
29346
22469
36956
lock,sec
94652
98517
93699
rate, Hz
0.31
0.23
0.39
double coincidence samples (S2 playground)
off-time samples
are produced during
the production stage
independent on GW
samples
raw triple coincidence rates
triple coincidence:
time window: 20 ms
frequency gap: 0 Hz
 ± 0.04 mHz
expect reduce background down to <10 mHz using final selection cuts: r-statistics, event confidence, veto, …
S.Klimenko, December 2003, GWDAW 2

6. “BH-BH merger” band off-time triple coincidence sample
raw triple coincidence rates
off-time triple coincidence sample
expect BH-BH mergers
(masses >10 Mo)
in frequency band
< 1 kHz
(BH-BH band)
S2 playground
background of
0.15 ± 0.02 mHz
expect < 1 mHz
after final cuts
S.Klimenko, December 2003, GWDAW 2

7. Simulation hardware injections
software injection into all three interferometers:
waveform name
GPS time of injection
{q, j,Y}          -  source location and polarization angle
T {L1,H1,H2}  -  LLO-LHO delays
F+{L1,H1,H2}  -  + polarization beam pattern vector
Fx {L1,H1,H2}   -  x polarization beam pattern vector
use exactly the same pipeline for processing of GW and simulation triggers.
sine-Gaussian injections
16 waveforms: 8-Q9 and 8-Q3
F+ {1,1,1} , Fx {0,0,0}
BH-BH mergers ( Mo)
10 pairs of Lazarus waveforms {h+,hx}
all sky uniform distribution with calculation {F+,Fx} for LLO,LHO
t –duration
f0-central frequency
S.Klimenko, December 2003, GWDAW 2

8. hardware injections H1H2 pair
SG injections [ 100Hz, 153Hz , 235Hz, 361Hz, 554Hz, 850Hz, 1304Hz 2000Hz ]
good agreement between injected and reconstructed hrss
good time and frequency resolution
H1H2 pair
S.Klimenko, December 2003, GWDAW 2

9. detection efficiency vs hrss
@235 Hz
robust
with respect
to waveform Q
fo, Hz
100
153
235
361
554
850
1034
2000
h50%, Q9
40.
20.
4.8
7.5
7.2 -
16.
h50% , Q3
36.
14.
6.0
6.6
8.6
10.
17.
30.
x10-21
S.Klimenko, December 2003, GWDAW 2

10. S2 playground simulation sample
timing resolution
S2 playground simulation sample
sT=4ms
1% loss
12% loss
time window >= 20 ms  negligible loss of simulated events (< 1%)
S.Klimenko, December 2003, GWDAW 2

11. Signal reconstruction
Use orthogonal wavelet (energy conserved) and calibration.
reconstructed log10(hrss)
mean amplitude
frequency
S.Klimenko, December 2003, GWDAW 2

12. BH-BH merger injections
BH-BH mergers (Flanagan, Hughes: gr-qc/ v2 1997)
duration :
start frequency :
bandwidth:
Lazarus waveforms
(J.Baker et al, astro-ph/ v1)
(J.Baker et al, astro-ph/ v1)
all sky simulation using
two polarizations and
L & H beam pattern functions
S.Klimenko, December 2003, GWDAW 2

13. Lazarus waveforms: efficiency
all sky search:
hrss(50%)
mass, Mo 10 20 30 40 50 60 70 80
100
hrss(50%) x 10-20
4.5
2.4
2.0
1.8
1.5
1.7
2.2
3.4
7.1
S.Klimenko, December 2003, GWDAW 2

14. Lazarus waveforms: frequency vs mass
expected BH-BH frequency band – Hz
S.Klimenko, December 2003, GWDAW 2

15. Summary
analysis pipeline is fully operational (production, post-production, simulation).
robust detection of SG waveforms with different Q
pipeline sensitivity (no data conditioning yet)
(5-20) optimal detection (SG waveforms).
~ all sky BBH merger search (Lazarus waveforms)
 plan efficiency study using EOB & ABFH merger waveforms
background: raw triple coincidence rates
full band (4kHz): ~1 mHz
“BH-BH band” (<1kHz): ~0.15 mHz
 after all selection cuts expect <1 mHz background rate
for full S2 data set
S.Klimenko, December 2003, GWDAW 2