Applications
Contacts: F. Garcia, P. Gasik, D. Gonzalez Diaz, G. Aielli, G. Pugliese, R. Farinelli
WG2 Indico category: https://indico.cern.ch/category/16508/
Contact email: DRD1-WG2-convenors@cern.ch
MUON SYSTEMS
Muon systems are often associated with gaseous detectors, representing one of the most successful technologies and combining the typical requirements for this application: the ability to easily instrument very large surfaces, good space-time resolution, high efficiency and lightweight. In the future, muon systems, which in a collider environment are usually surrounding the experiment calorimeters, could be in some design partially or totally merged with them, sharing similar challenges. Moreover, such systems play a key role in tracking and tagging par- ticles from rare-event decays of Dark Matter and long-lived particles over large detection volumes.
INNER AND CENTRAL TRACKING WITH PARTICLE IDENTIFICATION CAPABILITY (DRIFT CHAMBERS, STRAW CHAMBERS AND TIME PROJECTION CHAMBERS)
Drift Chambers
Large-volume drift chambers have been proposed as tracking and particle identification devices for the next generation of lepton colliders both at FCC-ee (CERN) and at CEPC (IHEP China) Analogous proposals exist for the next gen- eration of flavor factories SCTF (Russia, China) and could easily be adapted for Electron-Ion Colliders. Drift chambers provide high-precision tracking and ex- cellent particle identification.
Straw Chambers
Straw chambers can cover a broad range of applications by choosing the ap- propriate specifications, such as straw tube diameter, tube wall thickness, length of the straw, gas mixture or the straw signal information registered by the elec- tronic readout. The WG1 section ( 3.1) lists examples and applications for straw detector systems currently in development or planned for the future. For applications at new accelerators with higher intensities, the general R&D goals for straw detectors are i) high particle-flux capability of about 100 kHz/cm2 and ii) extended longevity up to charge loads as high as 10 C/cm, both being within a factor of ten above the current standards.
Time Projection Chambers
Future collider facilities (such as the ILC, FCC-ee or CEPC) will have in- creased needs for the next generation of Time Projection Chambers (TPCs), which should accommodate requirements such as: • good dE/dx resolution, partly driven by a good gain uniformity; • very low gain × Ion Back Flow figure to drastically reduce space charge distortions; • high readout granularity to cope with the particle multiplicity; • electronics with low power dissipation to meet the increased density of read- out channels. • large area coverage at reduced low cost, relying on lightweight mechanical structures based on composite materials
CALORIMETRY
In future high-energy lepton colliders (ILC, CLIC, muon collider, etc) precision energy measurements and triggering will be challenging. Particle flow is a new approach to calorimetry which promises to achieve a jet energy resolution that is more than a factor of two better than traditional calorimetric approaches. It is predicated on the ability to reconstruct the energies of the individual particles in a jet. In particle-flow calorimetry, the energy deposits from charged particles, photons and neutral hadrons are separated. The charged-particle energies are well measured from the associated track momentum and the calorimeters are mainly used for the (neutral) electromagnetic and hadronic components. Particle-flow calorimetry requires highly segmented calorimeters and sophis- ticated reconstruction algorithms for tracking individual particles within a shower.
PHOTO-DETECTORS (PID)
The main advantages of employing a gaseous medium for photon detection are the low material budget, negligible sensitivity to magnetic fields, and cost-effectiveness, especially for large-area systems. The main R&D challenges for this application include: • preserving the photocathode efficiency by suppressing ion backflow and de- veloping more robust photoconverters; • development of very low noise, large dynamic range front-end electronics (FEE); • improvement of the detector performance in terms of spatial and time reso- lution, along with a fast charge collection to maximize the rate capability; • in addition, for TRD systems, a better separation between the transition ra- diation and the ionization process is desired.
TIMING DETECTORS
Two main technologies are currently under use in this area: tRPCs based on the multi-gap technology and MPGD detectors such as those resorting to Cherenkov light (PICOSEC). Depending on the use case, developments focus on timing ca- pabilities of 20-50 ps and rate capabilities of 30-150 kHz/cm2, where different technologies can be used to fulfill the most challenging requirements:
RE-TPCS (RARE EVENTS, NEUTRINO PHYSICS, ACTIVE TARGETS)
TPCs employed in the field of rare event searches (historically referring -largely- to research where natural radioactivity can limit experiment performance), and by extension, those employed in neutrino physics or as active targets for nuclear- reaction studies, share many methodological and technological characteristics. This makes them markedly distinct from large-volume tracking technologies dis- cussed in WP2-4.
BEYOND HEP
Gaseous-detection technologies are widely used. The main applications related to HEP have been listed above, and the main goals and necessary developments are described in the tables corresponding to the eight work packages identified. From a broad point of view these developments can be seen, ultimately, as focused in achieving: i) low-cost and mass production capabilities through collaboration with industries, ii) high space-time resolution for detecting photons or charged parti- cles, iii) outstanding imaging capabilities and energy reconstruction, iv) enhanced sensitivity to low-energy deposits.