A novel liquid argon (LAr) purity monitor was developed with a sensitivity to elec-tronegative impurities of the order of ppb (O 2 equivalent). Such a high purity is e.g. needed in a LAr drift chamber. The principle is to measure the lifetime of quasifree electrons in LAr, since this is the important parameter for the operation of a drift chamber. Free electrons are produced by ionizing the LAr...

The BABAR detector at PEP-II will operate in a highluminosity e+e collider environment near the (4S) resonance with the primary goal of studying CP violation in the B meson system. In this environment, typical physics events of interest involve multiple charged particles. These events are identified by counting these tracks in a fast first level (Level 1) trigger system, by reconstructing the t...

years from now. The understanding of intrinsic limits on the spatial accuracy of drift chambers, and the development of new methods for calibrating them, are therefore still relevant. The present talk attempts to review the state of the art. In order to see what are the main questions to be asked, I have summarized in Table 1 the main characteristics of the drift-chamber detectors proposed for ...

Homogeneous nucleation of a vapor in the presence of the loss of clusters by diffusion and thermophoretic drift is investigated. Analytical results are obtained for the cluster size distribution and the rate of nucleation by solving the modified kinetic equation for nucleation. The implications of cluster loss by diffusion and phoretic drift on the onset of the homogeneous nucleation of silicon...

Revised 2003 (see the various sections for authors). In this section we give various parameters for common detector components. The quoted numbers are usually based on typical devices, and should be regarded only as rough approximations for new designs. More detailed discussions of detectors and their underlying physics can be found in books by Ferbel [1], Grupen [2], Kleinknecht [3], Knoll [4]...

The first portion of the BABAR experiment Level 1 Drift Chamber Trigger pipeline is the Track Segment Finder (TSF). Using a novel method incorporating both occupancy and drift-time information, the TSF system continually searches for segments in the supercells of the full 7104-wire Drift Chamber hit image at 3.7 MHz. The TSF was constructed to operate in a potentially high beam-background envir...

The amplifier described in this note is intended to interface an existing preamplifier chip under development by D. Dorfan and N. Spencer at UCSC with a conventional ADC module. The preamp chip provides differential-voltage-mode outputs capable of driving 50-Ω loads. However, the differential channels are made up of emitter-followers with approximately 4Vbe of voltage difference under zero sign...