Author/Authors :
Middelkamp، نويسنده , , Peter and Antinori، نويسنده , , F. and Barberis، نويسنده , , D. and Becks، نويسنده , , K.H. and Beker، نويسنده , , H. and Beusch، نويسنده , , W. and Burger، نويسنده , , P. and Campbell، نويسنده , , M. and Cantatore، نويسنده , , E. and Catanesi، نويسنده , , M.G. and Chesi، نويسنده , , E. and Darbo، نويسنده , , G. and Auria، نويسنده , , S.D. and Davia، نويسنده , , C. and Di Bari، نويسنده , , D. and Di Liberto، نويسنده ,
Abstract :
Four silicon pixel detector planes are combined to form a tracking telescope in the lead ion experiment WA97 at CERN with 290 304 sensitive elements each of 75 μm by 500 μm area. An electronic pulse processing circuit is associated with each individual sensing element and the response for ionizing particles is binary with an adjustable threshold. The noise rate for a threshold of 6000e− has been measured to be less than 10−10. The inefficient area due to malfunctioning pixels is 2.8% of the 120 cm2. Detector overlaps within one plane have been used to determine the alignment of the components of the plane itself, without need for track reconstruction using external detectors. It is the first time that such a big surface covered with active pixels has been used in a physics experiment. Some aspects concerning inclined particle tracks and time walk have been measured separately in a beam test at the CERN SPS H6 beam.
