PERFORMANCE STUDIES AND DETECTOR OPTIMIZATION
The best detector and analysis techniques for the future of particle physics with colliders
Future electron-positron colliders require detector concepts designed and optimised to exploit Particle Flow reconstruction algorithms (PFA), allowing the reconstruction and separation of individual particles produced in the collisions while maximising the information provided by the tracking systems.
The International Large Detector (ILD) is a mature detector concept developed for high-precision physics at future electron-positron colliders. Its technologies, reconstruction strategies and optimisation studies provide an important framework for detector developments relevant to future facilities such as FCC-ee and the Linear Collider Facility (LCF).
To accomplish the desired physics goals using PFA, both the detector design and the event reconstruction tools have to be carefully optimised. The AITANA group is very active in this area, combining detector optimisation, reconstruction software and physics-performance studies.
The ILD detector concept is designed to exploit the full capabilities of Particle Flow reconstruction. This requires a large detector radius and a strong magnetic field to provide excellent separation of charged and neutral particles and to optimise the matching between reconstructed tracks and calorimetric energy deposits.
Precise tracking systems with a very low material budget are essential to maximise primary and secondary vertex reconstruction, momentum resolution and heavy-flavour tagging performance. The innermost layers of the tracking system are located very close to the interaction point, providing the precision required for demanding flavour and Higgs physics measurements.
Particle Flow reconstruction also requires highly granular calorimetric systems, providing efficient separation of nearby particles and precise association between calorimeter clusters and tracks reconstructed in the inner detector. Excellent angular coverage and detector hermeticity are similarly required to meet the precision goals of future electron-positron collider experiments.
The ILD layout can be divided into four main groups: the inner vertexing and tracking systems, the calorimetric systems, the magnetic coil and the muon detection system. Several technological solutions continue to be studied and optimised for these subsystems.
Originally developed in the context of linear collider studies, ILD now provides a mature technological and reconstruction framework that can be exploited and adapted for detector studies at future facilities, including FCC-ee and LCF.
The physics analyses carried out by members of AITANA, involving heavy leptons (top-quarks, taus), heavy flavours and Higgs bosons in the final state, require highly performant reconstruction algorithms and optimised detector designs.
AITANA has contributed to the development of reconstruction tools specifically designed for future electron-positron colliders, including the VLC jet-clustering algorithm, and has played a leading role in the design and optimisation of forward tracking systems.
The group also contributes actively to the optimisation of particle-identification algorithms, including methods based on time-projection-chamber information and new approaches exploiting precise timing measurements. These developments are directly relevant to the demanding detector-performance requirements of future facilities such as FCC-ee and LCF.
All these activities exploit the strong synergies between physics analysis, detector R&D, reconstruction software and detector simulation, allowing detector technologies and reconstruction strategies to be evaluated directly in terms of their impact on the physics potential of future collider experiments.
A Irles is the chair of the Collaboration Board of ILD.
