Enhancing the CDF's B physics program with a faster data acquisition system.

Abstract

The physics program of Run II at the Tevatron includes precision electroweak measurements such as the determination of the top quark and W boson masses; bottom and charm physics including the determination of the B{sub s} and D{sup 0} mixing parameters; studies of the strong interaction; and searches for the Higgs particle, supersymmetric particles, hidden space-time dimensions and quark substructure. All of these measurements benefit from a high-resolution tracking detector. Most of them rely heavily on the efficient identification of heavy flavored B hadrons by detection of displaced secondary vertices, and are enhanced by the capability to trigger on tracks not coming from the primary vertex. This is uniquely provided by CDF's finely-segmented silicon detectors surrounding the interaction region. Thus CDF experiment's physics potential critically depends on the performance of its silicon detectors. The CDF silicon detectors were designed to operate up to 2-3 fb{sup -1} of accumulated pji collisions, with an upgrade planned thereafter. However, the upgrade project was canceled in 2003 and Run II has been extended through 2011, with an expected total delivered integrated luminosity of 12 fb{sup -1} or more. Several preventive measures were taken to keep the original detector operational and maintain its performance. Themore » most important of these are the decrease in the operating temperature of the detector, which reduces the impact of radiation exposure, and measures to minimize damage due to integrated radiation dose, thermal cycles, and wire bond resonance conditions. Despite these measures the detectors operating conditions continue to change with issues arising from radiation damage to the sensors, aging infrastructure and electronics. These, together with the basic challenges posed by the inaccessibility of the detector volume and large number (about 750 thousand) of readout channels, make the silicon detector operations the single most complex and high priority job in the CDF experiment.« less