Tracking with the MINOS Time Projection Chamber

Abstract

We report on the performance of the MINOS Time Projection Chamber developed as a vertex tracker to study exotic nuclei produced from hydrogen-induced knockout via in-beam γ-ray and invariant-mass spectroscopy. In-beam measurements with 4He and 20Ne beams at 200 and 350 MeV/nucleon, respectively, were performed at the HIMAC facility. The tracking algorithm for protons after quasi-free scattering is described. Realistic simulations and physics experiments are compared and show a good agreement. The vertex position resolution reaches 5 mm FWHM, mostly from re-scattering with the target and the Aluminum reaction chamber. The overall efficiency of vertex reconstruction is also benchmarked with the first experimental campaign data performed at the RIBF, confirming an overall efficiency better than 90% for physics experiments.