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Silicon tracking detectors operated at high luminosity collider experiments pose a challenge for current and future readout systems regarding bandwidth, radiation, space and power constraints. With the latest developments in wireless communications, wireless readout systems might be an attractive alternative to commonly used wired optical and copper based readout architectures. The WADAPT group (Wireless Allowing Data and Power Transmission) has been formed to study the feasibility of wireless data transmission for future tracking detectors. These proceedings cover current developments focused on communication in the 60 GHz band. This frequency band offers a high bandwidth, a small form factor and an already mature technology. Motivation for wireless data transmission for high energy physics application and the developments towards a demonstrator prototype are summarized. Feasibility studies concerning the construction and operation of a wireless transceiver system have been performed. Data transmission tests with a transceiver prototype operating at even higher frequencies in the 240 GHz band are described. Data transmission at rates up to 10 Gb/s have been obtained successfully using binary phase shift keying.

Linear systems theory is used for the numerical assessment of the detective quantum efficiency (DQE) of the hybrid semiconductor pixel detector DIXI. The Monte Carlo based code GEANT is used to simulate the photon transport in the sensor, charge transport modeling is treated analytically and the readout chip is simulated using PSPICE. The DQE for two differently shaped X-ray spectra of the same quality and for different operational conditions of the readout chip regarding the discrimination level are computed in order to validate the model. The model described in this paper can be adopted for optimizing the detector. Index Terms--Cascaded linear system, detective quantum efficiency (DQE), hybrid pixel detector, X-ray imaging.

Presents information on a programmable fast trigger system for the wide angle shower apparatus (WASA) experiment at the Svedberg Laboratory in Uppsala, Sweden. Levels of the hardware architecture for minimum signal delay times; Description of the WASA detector; Background of the three-level trigger system.

In continuous systems simulation a model is built as a system of differential equations. An implicit assump tion is that the number of items is so large that the changes can then be regarded as continuous. How ever, many systems can be modeled by differential equations when the numbers involved are moderately large. Such systems show stochastic variations that can be described in terms of events per time unit. If the events happen one at a time, and if the number of events during the interval is independent of both the number of past events and the times these events oc curred, we have a Poisson process. The system's variations can be modeled by replacing the flow to or from a state during the integration step with a Pois son probability. This not only adds variations to the model, but can also reveal system properties not cov ered by continuous system simulation. Furthermore, the "intensity parameter" controlling the flow may vary over time without further problems. [ABSTRACT FROM PUBLISHER]

Background: Cytologic screening and follow-up can reduce the incidence of cervical cancer by detection and removal of precursor lesions. It is unknown, however, whether differences in histopathologic criteria for these precursor lesions affect the benefit of screening. These criteria may be difficult to study, but they are likely to be reflected in reported incidence of in situ cancer in small areas of Sweden.Purpose: Our purpose was to test the hypothesis that the benefit of screening can be predicted by histopathologic criteria as reflected in the reported incidence of cancer in situ.Methods: Incidence data were from the Swedish National Cancer Registry. Regression models showing the relationship between in situ and invasive cancer were formulated and estimated. Each county (total, 24) was a unit of measurement, and adjustment was made for the incidence of invasive cancer before screening.Results: During population-based screening in Sweden, the incidence of cancer in situ varied about fourfold among the 24 counties, which indicates that the criteria used to diagnose cancer in situ differed markedly. No statistically significant (P < .05) associations were found between the incidence of cancer in situ in 1965, 1970, or 1975 and the reduction in invasive cancer 5, 10, or 15 years later. According to the best-fitting model, detection of 100 extra cases of cancer in situ per 100,000 women per year in 1975 resulted in a reduction of 1.0 (95% confidence interval [CI] = -1.6-3.7) cases of invasive cancer 10 years later. The corresponding best model estimate implied a reduction of 4.6 cases (95% CI = 1.5-7.7) in a model restricted to cancer in situ in patients aged 20-50 years (when organized screening took place), invasive cancer in patients aged 30-60 years, and cancer in situ measured in 1970.Conclusions: The absent, or at most weak, association between detection of cancer in situ and subsequent reduction in invasive cancer indicates that relaxed histopathologic criteria for cancer in situ may result in extensive, unnecessary treatment of lesions that would regress spontaneously.Implication: Further studies are urgently needed to enable identification of neoplasms likely to progress to invasive, fatal disease. [ABSTRACT FROM AUTHOR]