Virgo Data Analysis for C6 and C7 Engineering Runs

The interferometric gravitational wave detector Virgo is completing the commissioning phase, and it is close to commencing with scientific data taking. In 2005, before a temporary shutdown of the interferometer, two commissioning runs were performed: the C6 run from July 29th to August 12th, and the C7 run from September 14th to 19th. The sensitivity of the detector during these commissioning runs was not yet at an interesting level for scientific observations. However, the bandwidth and stability of the detector is already sufficient to perform important studies in preparation for the acquisition and analysis of astrophysically important data. The data have therefore been analyzed by the Virgo physics groups, with the goal of testing the analysis pipelines and developing veto strategies. The results also allowed a better understanding of the noise sources, thus providing useful feedback to the commissioning team.