First, software and design updates in COMET’s software suite, ICEDUST, are evaluated holistically, implementing a comparative analysis system to observe the relative differences in particle distributions following large-scale changes. Geant4.10.6 was validated against previous productions. The latest official large-scale Monte-Carlo production, MC6 was found to produce 8.16\% more muons persisting through the transport solenoid, but 16.87\% fewer stopped muons in the Muon Stopping Target; an overall decrease in expected muon stopping efficiency.

Next, ICEDUST’s ability to replicate the NA61/SHINE T2K replica target data was evaluated for $\pi^{\pm}$, $K^{\pm}$, and proton distributions. While normalised distributions of simulations seem to fit experimental results well, unormalised data presents consistent factors of difference between experiment and simulation across the distributions for most data bins. Although some of the quoted parameters in simulation are contested in this study, within reason the ICEDUST distributions work well in replicating experimental data, improving on discrepancies noted in the original study. However, P$<1$ GeV/c momenta exhibit the largest differences, necessitating further study in the consideration of the COMET experiment’s sub-GeV focus.

Finally, the COMET curved transport solenoid was commissioned in Phase-$\alpha$, analysing simulated and experimental positive pion data.
Pion transport was confirmed via the investigation of $\pi^{+} \rightarrow \mu^{+} \rightarrow e^{+}$ decay chains, with $\tau_{\pi^{+}} = 23.4 \pm 2.3$ns for candidate $\pi^{+}$ and $\tau_{\mu^{+}} = 2780 \pm 250$ns for candidate $\mu^{+}$, within expectations of pion and muon lifetimes.
The estimated decay chain rate was $14.8^{+2.3}_{-4.1} \times 10^{13}$ per Proton on Target (PoT), within the expectation of $15.8 \pm 0.5 \times 10^{13}$ per PoT from simulation, confirming appropriate estimation of low-energy physics. An exploratory study is also performed on the dependence of pion trajectories on the position and angle of pions exiting the transport solenoid, with a novel Beam Masking system collimating incident pions.