Speaker
Description
ALADDIN (An LHC Apparatus for Direct Dipole moments INvestigation, https://aladdin.web.cern.ch/) is a proposed compact fixed-target experiment at the LHC, designed to enable precise measurements of charm baryon electromagnetic dipole moments. The experiment leverages an innovative storage-ring layout that redirects protons from the beam halo onto a solid target, coupled with a bent crystal. This setup produces forward-boosted charm baryons, which are then channeled through the crystal. By exploiting spin precession induced by the channelling effect in the bent crystal, ALADDIN aims to measure both the magnetic and electric dipole moments through an analysis of the polarization of decaying charm baryons. The experimental apparatus consists of a 4.4 m-long spectrometer and a 20 m-long RICH detector for particle identification. It is designed for installation in the LHC Insertion Region 3 during Long Shutdown 3 (and onwards), requiring no civil engineering and having minimal impact on LHC operations, with data-taking planned for Run 4+5. A proof-of-principle test at the LHC, TWOCRYST (https://twocryst.web.cern.ch/), has concluded several successful dedicated machine development runs in 2025 and 2026 ,before LS3. TWOCRYST demonstrated the feasibility of the concept and detailed data analysis is ongoing. The experiment’s Letter of Intent has been submitted to the LHCC (https://cds.cern.ch/record/2905467), which has approved the collaboration to proceed with a technical proposal in 2026-2027.