The CDF vertex time projection chamber system

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 268; no. 1; pp. 75 - 91
• Main Authors: Snider, F., Binkley, M., Huth, J., Kephart, R., Newman-Holmes, C., Palanque, S., Patrick, J., Yarema, R., Yeh, G.P., Zimmerman, T., Schub, M., Abe, F., Kondo, K., Mimashi, T., Sekiguchi, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 10.05.1988
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/0168-9002(88)90594-3

The vertex time projection chamber (VTPC) system is one of the major components of the charged particle tracking system for the Collider Detector at Fermilab (CDF). The chambers cover about seven units of pseudorapidity (η) and must be capable of handling substantially more than the 30–35 charged particle tracks produced by typical p p collisions at center-of-mass energies o TeV. The chambers are optimized to provide the good pattern recognition in the r- z view required to locate the event vertex, measure the overall event topology, and to complement the r- φ tracking in the large axial wire drift chamber that surrounds them. The chambers provide r- z information using TDC data from sense wire signals. Information on the φ of tracks is obtained from cathode pad signals on a subset of chambers read out by a FADC system. A similar system measures d E/d x of tracks in the forward cones surrounding the exiting beams. Because of the large number of photons that pass through the detector during each collision, novel techniques are required to reduce the amount of material in the chamber. These techniques include a custom surface mount integrated circuit preamplifier, epoxy-graphite and Kapton covered foam structural members, and miniature coaxial signal cables. The mechanical construction of the chamber, radiation length vs angle, and details of the electronics are described. The event reconstruction, corrections, and preliminary performance results for 1.8 TeV p p collisions are also discussed.