Electronic Tracker Research Articles

The OPERA experiment and the first events from the CNGS neutrino beam

The aim of the OPERA experiment is to provide unambiguous evidence for the νμ↔ντ oscillation by looking at the appearance of ντ in a pure νμ beam. The detector is located on the high-energy, long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. The apparatus consists of a target made of lead/emulsion-films bricks complemented by electronic detectors. The neutrino interaction inside the bricks is tagged using the electronic trackers. In August 2006, a short CNGS run was successfully performed and a first sample of neutrino events was collected. Experiment description and results from the first CNGS run are reported in details.

Detecting the (quasi-) two-body decays of [formula omitted] leptons in short-baseline neutrino oscillation experiments

Novel detector schemes are proposed for the short-baseline neutrino experiments of next generation, aimed at exploring the large- Δm 2 domain of ν μ →ν τ oscillations in the appearance mode. These schemes emphasize good spectrometry for charged particles and for electromagnetic showers and efficient reconstruction of π 0→ γγ decays. The basic elements are a sequence of relatively thin emulsion targets, immersed in magnetic field and interspersed with electronic trackers, and a fine-grained electromagnetic calorimeter built of lead glass. These elements act as an integral whole in reconstructing the electromagnetic showers. This conceptual scheme shows good performance in identifying the τ (quasi-) two-body decays by their characteristic kinematics and in selecting the electronic decays of the τ .

Results of a first beam test of hadron blind trackers

We describe the experimental results of a new type of electron tracker, called Hadron Blind Detector or HBD. An HBD prototype was tested with gas mixtures of CF 4 with He or Ne and a parallel plate avalanche chamber having a CsI photocathode of eight pads. Beam tests confirm the large Cherenkov light bandwidth in the EUV region that can be obtained with such gas mixtures. It results in a large quality factor of about 500 cm −1 which allows HBD operation with a much shorter radiator thickness than conventional Cherenkov counters. Full electron efficiency was obtained, while pions were rejected up to momenta of 9 GeV/ c. HBD is unique in measuring electron trajectories near the vertex, vetoing Dalitz pairs, and providing trigger on electrons among heavy hadron background. We discuss the use of such detectors for lepton identification and detection in high energy physics experiments and especially in heavy ion colliders.

Stability Criterion for a Hybrid Phase-Locked Loop Range Tracker

A currently tested high-performance electronic range tracker operating in a linear region and tracking a nearly stationary target can be modeled as a hybrid or gated phase-locked loop. A relationship for stability in this system is developed. The relationship is applicable to both Type I and Type II second-order hybrid phase-locked loop trackers.

An adaptive analogue tracker for automatic measurement of lung parameters

This paper describes the design and results obtained using simple electronic circuits specially designed for implementing a simple lung-parameter tracking algorithm for identification of the mechanical properties of the lung. Unlike the commonly used loop-flattening technique, the adaptive electronic tracker is able to monitor continuously the mechanical properties of the respiratory sysem. It is capable of tracking the rapid changes in lung parameters as the frequency of breathing changes. The design of the adaptive tracker is based on equation-error formulation and the global asymptotic stability of the adaptive tracking equations is guaranteed. The cheapness and simplicity of the tracker makes it suitable for clinical applications.