WG5 will be dedicated to the R&D of segmented detectors based either on scintillating fibres or on pixelated semiconductor detectors for high precision tracking, eventually exploiting the transition radiation for particle identification. The activities of this WG will be connected with those of WG1 (photon detectors).

WG5 - A: Scintillating Fibres
WG5.A focuses on the improvement of the performance SciFi trackers in high rate and high radiation environments. The topics listed below focus on improving the radiation hardness, granularity, light yield, and other performance characteristics of the scintillating fibre trackers. This working group is interested in the following topics:

• Studying the performance of scintillating fibres under ionising irradiation
• Development of novel fast, more radiation-hard scintillating fibres
• Studying the ageing of the base polymer over time, and its effect on fibre performance
• Development of SciFi detectors with photon timing information
• Development of beam instrumentation at future accelerators with fibres
• Development of higher granularity trackers beyond 0.25 mm for higher rate experiments
• Simulation and Development of novel fibre claddings
• Development of improved optical connections techniques with SiPMs and other photodetectors, e.g. microlenses
• Development of fibre ribbon and detector plane production techniques.
• Development of scintillating fibre trackers compatible with cryogenically cooled SiPMs
 

WG5 - B: Transition Radiation Detectors
WG4.5.B aims to develop a new type of device combining precise tracking and PID. Transition Radiation Detectors (TRDs) exploit the transition radiation (TR) emitted in the X-ray region by fast charged particles for PID. Traditional TRDs based on gaseous detectors are typically applied for electron/hadron separation exploiting the threshold Lorentz factor for TR emission. Here we propose to develop a novel TRD based on highly segmented pixel semiconductor detectors, which will be able to measure both the energies and the emission angles of TR X-rays. The simultaneous measurement of energies and emission angles will improve the PID performance with respect to TRDs based on gaseous detectors, where only the X-ray energies can be eventually measured. Such a TRD will be able not only to perform electron/hadron identification, but also to separate different species of hadrons in the TeV region, where other PID techniques cannot be applied. In addition, it will also provide precise tracking of charged particles.

An R&D activity on solid state TRDs has already been in progress for a few years. Several beam test campaigns have been carried out and, in parallel, dedicated Monte Carlo (MC) simulations of the TR process and of the detectors have been implemented. The working group is interested in the following activities:

• analysis of existing data;
• development of MC simulations;
• development and optimization of new radiators;
• development of highly pixelated detectors based on Si, GaAs and CdTe;
• development of readout chips associated to the detectors;
• beam test studies.