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The PUMA experiment was accepted at CERN in 2021. PUMA is in its construction phase. This document summarises the work performed in 2022 and focuses mainly on the design, construction and installation of the experiment.

Antiprotons as a probe to study short-lived isotopes remain unexploited despite past pioneering works with stable nuclei. In particular, low-energy antiprotons offer a very unique sensitivity to the neutron and proton densities at the annihilation site, i.e. in the tail of the nuclear density. Such studies with short-lived nuclei and low-energy antiprotons are the first motivation of the proposed antiProton Unstable Matter Annihilation (PUMA) experiment. Today, no facility provides a collider of low-energy radioactive ions and low-energy antiprotons: PUMA aims at transporting one billion antiprotons from CERN/ELENA to CERN/ISOLDE to perform the capture of low-energy antiprotons by short-lived nuclei, and probe in this way the so-far unexplored isospin composition of the nuclear-radial-density tail of radioactive nuclei.

Electron cloud (EC) has already been observed during normal operation of the PS, therefore it is necessary to study its in fluence on any beam instability for the future LHC Injector Upgrade (LIU). Two new electron cloud detectors have been discussed, developed and installed during the Long Shutdown (LS1) in one of the PS main magnets. The first measurement method is based on current measurement by using a shielded button-type pick-up. Due to the geometry and space limitation in the PS magnet, the button-type pick-up made of a 96%Al2O3 block coated with a thin layer of solvent-based Ag painting, placed 30 degrees to the bottom part of the vacuum chamber was installed in the horizontal direction where the only opening of the magnet coil is. The other newly developed measurement method is based on detection of photons emitted by the electrons from the electron cloud impinging on the vacuum chamber walls. The emitted photons are reected to a quartz window. A MCP-PMT (Micro-Channel Plate Photomultiplier Tube) with high magnetic field/radiation resistance and fast response is attached outside the quartz window behind two UV lenses and one UV mirror and then counts the photons during the beam operation.