L. Giordano

First joint gravitational wave search by the AURIGA-EXPLORER-NAUTILUS-Virgo Collaboration

We present a methodology of network data analysis applied to the search for coincident burst excitations over a 24 h long data set collected by AURIGA, EXPLORER, NAUTILUS and Virgo detectors during September 2005. The search of candidate triggers was performed independently on each of the data sets from single detectors. We looked for two-fold time coincidences between these candidates using an algorithm optimized for a given population of sources and we calculated the efficiency of detection through injections of templated signal waveforms into the streams of data. To this end we have considered the case of signals shaped as damped sinusoids coming from the galactic center direction. Our method targets an optimal balance between high efficiency and low false alarm rate, aiming at setting confidence intervals as stringent as possible in terms of the rate of the selected source models.

Virgo Data analysis for C6 and C7 engineering runs

F. Acernese , P. Amico, M. Alshourbagy , F. Antonucci , S. Aoudia, P. Astone , S. Avino, D. Babusci , G. Ballardin, F. Barone, L. Barsotti, M. Barsuglia , F. Beauville, S. Bigotta , S. Birindelli, M.A. Bizouard, C. Boccara, F. Bondu, L. Bosi, C. Bradaschia , S. Braccini,A. Brillet, V. Brisson, L. Brocco , D. Buskulic, E. Calloni, E. Campagna , F. Carbognani, F. Cavalier, R. Cavalieri, G. Cella, E. Cesarini, E. Chassande-Mottin , N. Christensen, C. Corda, A. Corsi, F. Cottone , A.-C. Clapson, F. Cleva, J.-P. Coulon, E. Cuoco , A. Dari, V. Dattilo, M. Davier, M. del Prete, R. De Rosa, L. Di Fiore, A. Di Virgilio, B. Dujardin, A. Eleuteri, I. Ferrante , F. Fidecaro , I. Fiori, R. Flaminio, 2, J.-D. Fournier, O.Francois, S. Frasca , F. Frasconi, 11, L. Gammaitoni , F. Garufi, E. Genin , A. Gennai , A. Giazotto , G. Giordano, L. Giordano , R. Gouaty , D. Grosjean, G. Guidi, S. Hebri, H. Heitmann , P. Hello, S. Karkar, S. Kreckelbergh, P. La Penna, M. Laval, N. Leroy , N. Letendre , B. Lopez , Lorenzini, V. Loriette , G. Losurdo, J.-M. Mackowski, E. Majorana, C. N. Man, M. Mantovani , F. Marchesoni , F. Marion, J. Marque, F. Martelli, A. Masserot, M. Mazzoni, L. Milano, F. Menzinger, C. Moins, J. Moreau, N. Morgado, B. Mours, F. Nocera, A. Pai, C. Palomba, F. Paoletti, 11, S. Pardi, A. Pasqualetti , R. Passaquieti , D. Passuello , B. Perniola, F. Piergiovanni, L. Pinard, R. Poggiani , M. Punturo , P. Puppo , K. Qipiani, P. Rapagnani , V. Reita, A. Remillieux, F. Ricci, I. Ricciardi, P. Ruggi , G. Russo, S. Solimeno, A. Spallicci, R. Stanga , T. Marco , M. Tonelli, A. Toncelli , E. Tournefier, F. Travasso , C. Tremola, G. Vajente , D. Verkindt, F. Vetrano , A. Viceré, J.-Y. Vinet, H. Vocca and M. Yvert Laboratoire d’Annecy-le-Vieux de Physique des Particules (LAPP), IN2P3/CNRS, Université de Savoie, Annecy-le-Vieux, France;

Adaptive Filters for Detection of Gravitational Waves from Coalescing Binaries

In this work we propose a new strategy for gravitational waves detection from coalescing binaries, using Adaptive Line Enhancer filters. An analysis of the filters performance is shown in terms of the tracking capability and determination of filter parameters. Furthermore, receiver operating characteristics are derived, by extensive Monte Carlo simulation studies. Some tests have been performed on simulated Virgo noise, demonstrating that adaptive filters are promising both for the small computational power needed (with respect to the matched filter) and for the statistical robustness of the algorithms used.

IIR adaptive filters for detection of gravitational waves from coalescing binaries

In this paper we propose a new strategy for gravitational waves detection from coalescing binaries, using IIR Adaptive Line Enhancer (ALE) filters. This strategy is a classical hierarchical strategy in which the ALE filters have the role of triggers, used to select data chunks which may contain gravitational events, to be further analyzed with more refined optimal techniques, like the the classical Matched Filter Technique. After a direct comparison of the performances of ALE filters with the Wiener-Komolgoroff optimum filters (matched filters), necessary to discuss their performance and to evaluate the statistical limitation in their use as triggers, we performed a series of tests, demonstrating that these filters are quite promising both for the relatively small computational power needed and for the robustness of the algorithms used. The performed tests have shown a weak point of ALE filters, that we fixed by introducing a further strategy, based on a dynamic bank of ALE filters, running simultaneously, but started after fixed delay times. The results of this global trigger strategy seems to be very promising, and can be already used in the present interferometers, since it has the great advantage of requiring a quite small computational power and can easily run in real-time, in parallel with other data analysis algorithms.