The CDFII Time-Of-Flight Detector and Impact on Beauty Flavor Tagging
The new CDFII detector incorporates a Time-of-Flight detector (TOF), em-ploying plastic scintillator bars and ﬁne-mesh photomultipliers. Since August 2001 the TOF system has been fully instrumented and integrated into the CDFII data acquisition system. With a design goal of 100 ps resolution the TOF system will pro-vide at least two standard deviations separation between K ± and π ± for momenta p < 1 . 6 GeV/c , complementing low momentum particle identiﬁcation by means of the speciﬁc ionization energy loss measured in the drift chamber. We describe the design of the TOF detector and discuss the current status of its calibration and initial performances. Finally we review the expected impact of the TOF detector in the ﬂavor tagging of neutral B S meson.
Front end electronics for the CDF-II Time-of-Flight system
A Time-of-Flight detector (TOF) has been added to the CDF-II experiment to provide charged kaon identification primarily for neutral B meson flavor determination. The TOF front end electronics system has 432 channels and is designed to run at the 7.58 MHz bunch crossing rate in CDF. The electronics contributes less than 25 ps to the anticipated TOF timing resolution of 100 ps, which is dominated by photon statistics. This paper describes the design and implementation of the electronics as well as the initial in situ performance.
Science fairs as learning tool for teaching excellence
Science fairs are usually considered to be a pedagogical and cultural activity that involves the students actively. Gifted students need challenges to further develop their skills while maintaining the motivation level. Science fairs may provide the informal environment that will request and allow these students of excellence to challenge themselves by developing a scientific research project. Despite being well known in different countries, in Portugal first steps are being made on the use and implementation of science fairs as effective pedagogical tool. In this work, we will present a 4 years study that was developed on a Portuguese school with the main goal of evaluating the advantages of this informal way of teaching. The study includes an analysis of the evolution of the students’ knowledge that have participated, or visited, the different science fairs. Some advices for the implementation of these projects will be given. The motivation of the students was monitored as well as the knowledge and skills effectively improved by this activity.