Speaker
Description
The ALICE Forward Calorimeter (FoCal) detector upgrade is designed to probe hadronic matter, its gluon density and the parton distribution functions at Bjørken-$x$ in the order of and smaller than 10⁻⁶. Located 7$\,\mathrm{m}$ away from the LHC interaction point, it will cover a pseudo-rapidity range of 3.2 < η < 5.8. The calorimeter will be composed of a 20-layer Si-W sampling electromagnetic calorimeter and a copper-scintillating fibre hadronic calorimeter in "spaghetti" design with SiPM readout. Datataking is planned for LHC Run 4, starting from 2030.
One of the central and novel features of the FoCal detector are the two high-granularity pixel layers in the electromagnetic calorimeter. These layers, located at layer 5 and 10, are used to identify two photon showers with narrow opening angle from decays of neutral mesons, and thus to enhance the signal of isolated photons. In order to achieve this, two electromagnetic showers need to be resolved on the mm-scale. Nearly 2000 ALPIDE MAPS chips with a pixel size of ~29 x 27 µm² will be installed per layer, organized in aluminum carriers which house so-called strings with 15 chips in a row (i.e. transversal length of 45cm). These strings will be produced with flexible printed-circuit boards, to which the ALPIDEs will be assembled and connected with Single-Point TAB bonding technology.
This poster will give a comprehensive overview of the FoCal pixel layer project. We will present the expected performance for the two-shower discrimination power, its contribution to the detector's physics performance and put prototype results from testbeams into context. Furthermore the readout scheme and the trigger concept, the expected data rates and (in-)efficiencies will be subject to this contribution. Lastly, we will report on the plan for production readiness as well as the current status of prototyping.
| Category | Experiment |
|---|---|
| Collaboration (if applicable) | ALICE |
