for the Collaboration GWDAW 2005 Status of inspiral search in C6 and C7 Virgo data Frédérique MARION

GWDAW C6 & C7 runs C6  14 days  86% duty cycle (in science mode)  Factor 2 variation in the horizon over the course of the run C7  5 days  65% duty cycle  Detector sensitivity also not stationary Optimally oriented [1.4,1.4] M  (SNR=8)

GWDAW Inspiral online analysis Both pipelines, Merlino and MBTA, ran online during C6 and C7, getting data from online h-reconstruction  Monitoring information provided »Lists of loudest events »Plots for monitoring web pages MBTA Hardware injections

GWDAW C6 hardware injections 56 inspiral hardware injections  4 different periods, [1.4,1.4] M , SNR ranging from ~15 to 25 All detected  Check timing and mass estimation accuracy  Check SNR recovery ~ 10% loss might be due to sensitivity non-stationarity MBTA

GWDAW C7 hardware injections 2 periods of inspiral injections  [1.32, 1.36] M , SNR ~ 20 Detected with good accuracy  Issue with some injections having a bad  2 »under investigation Merlino

GWDAW Smaller variations still present Non-stationarities: C6 Evolution in time of the frequency at which half of the SNR is integrated  Change in the shape of the PSD ± 10% variations on short time scales (~15 min)

GWDAW Non-stationarities: C7 l Variations of the PSD on short time scales not obvious to follow with adaptive mechanisms Same kind of variations observed in C7

GWDAW C6 analysis: quality cuts (I) C6 first six days  Horizon very unstable  “Bump” going up and down in Hz region of sensitivity curve (stray beam)  Leave this first part of the run aside Focus on remaining 8 days Dark fringe spectrum

GWDAW C6 analysis: quality cuts (II) Skip first five minutes after relock Use auxiliary channels to identify obvious sources of high SNR triggers, e.g.  Saturations in frequency stabilization loop  Glitches on actuator coil drivers

GWDAW C6 analysis: SNR distribution [ ] M  analysis  ~ 170 hours of data Very loud events eliminated by basic quality cuts Tail of distribution still extends to high values  Even strong, the hardware injections (in red) do not dominate the noise MBTA Inspiral injections Burst injections

GWDAW MBTA C7 analysis [ ] M  analysis  ~ 80 hours of data C7 SNR distribution slightly better than C6 Merlino A relatively quiet 10 hours long period

GWDAW C7 software injections Systematic studies (efficiency,  2 test) with Merlino on software injections performed during C7 quiet period  see poster by L.Bosi

GWDAW hardware injection noise event C6: a posteriori vetoes SNR distribution between low and high frequency bands   2 2 bands noise event Shawhan-Ochsner veto  Look at output of matched filter in time domain

GWDAW  2 2 bands < 100 Samples above threshold < 30  2 2 bands < 100 C6: SNR with vetoes Bulk of distribution unchanged High SNR tail definitely improved  Hardware injections almost stand out

GWDAW C7: vetoes Behavior similar to C6

GWDAW C7: SNR with vetoes Loudest surviving event has SNR < 20  2 2 bands < 40 Samples above threshold < 30  2 2 bands < 40

GWDAW Conclusion C6 and C7 data have extra-galactic sensitivity to neutron star inspirals Not science quality data  Detector behavior glitchy and not stationary Preliminary analysis  Two pipelines operational for online and offline analysis  Hardware injections, quality cuts, a posteriori vetoes Pursue investigations  Learn as much as we can from those data in order to get prepared for the science data to come next year