Speaker
Description
The ALICE 3 apparatus is proposed as a major ALICE upgrade for the CERN LHC Run 5 (starting in 2036). The ALICE 3 Inner Tracker includes an ultra-light MAPS-based Vertex Detector located within retractable secondary-vacuum cases with the LHC beam pipe. By closing to an innermost radius of 5 mm after beam stabilization, the Vertex Detector provides unprecedented track pointing resolution, especially at low transverse momentum pT: it reaches, for example, 10 μm in both the transverse and longitudinal directions at pT = 200 MeV/c. Such precision enables, among others, novel studies of the quark-gluon plasma with (multi)heavy-flavour hadrons and with low-mass dielectrons. Reaching such performance requires a next-generation Vertex Detector with enhanced spatial resolution, radiation hardness, and material budget optimization.
The present contribution focuses on the studies for selecting and optimizing the components to be used in the secondary vacuum cases under at pressures as low as 10-9 mbar.
An ultra-high vacuum (UHV) facility has been developed for the outgassing studies of the components of the vertex detector. To avoid contaminating the expected UHV conditions, all the detector components must meet the strict outgassing properties. For example, the ultralight reticulated vitreous carbon (RVC) foam, characterized by considerable radiation length, has been proven to be a good material for the mechanical support of silicon sensors. However, its high surface area and porous nature lead to significant H2O adsorption.
Together with RVC foam, there are many other components of this ITS3 vertex detector, such as optical fiber, electrical connector for powering & communication, MAPS sensors, wire bonding, gluing, and other types of foam to be investigated to ensure that they are vacuum compatible for the LHC beam pipe vacuum line. Moreover, the idea is to investigate the temperature-dependent outgassing behavior under UHV conditions, characterize its desorption kinetics, and propose mitigation strategies to minimize contamination in the LHC environment.
This contribution will show an overview of the Vertex Detector, along with the dedicated studies in the vacuum described above.
| Position | Postdoctoral Researcher |
|---|---|
| Affiliation | Politecnico di Bari & INFN Bari, Bari-Italy |
| Country | Italy |