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Bailey & Basu (2014) show analysis of density and mass-to-flux ratio maps forsimulations with either an ionisation profile which takes into accountphotoionisation (step-like profile) or a cosmic ray only ionisation profile. Weextend this study to analyse the effect of these ionisation profiles onvelocity structures, kinematics, and synthetic spectra. Clump regions are foundto occur at the convergence of two flows with a low velocity region andvelocity direction transition occurring at the junction. Models with evidentsubstructure show that core formation occurs on the periphery of these velocityvalleys. Analysis of synthetic spectra reveals the presence of largenon-thermal components within low-density gas, especially for models with thestep-like ionisation profile. All cores show small, sub-thermal relativemotions compared to background gas. Large deviations within this analysis aredue to the line of sight intersecting low- and high-density regions across thevelocity switch transition. Positive deviations correspond to a foreground coremoving away from the observer while negative deviations correspond to abackground core moving toward the observer. Comparison of velocities resultingfrom different ionisation profiles suggest that high ionisation fractions yieldsupersonic velocities, up to two times the sound speed, while regions with lowionisation fractions tend to be subsonic or mildly supersonic. This suggeststhat the transition to coherence within cores could be a transition betweenhigh and low ionisation fractions within the gas.

Kinematics in Partially Ionised Molecular Clouds: Implications for the Transition to Coherence