Population synthesis defaults

[maxbriel]

Based on recent works using POSYDON, for example Xing et al. (2025) and Chattaraj et al. (2026), there are parameter choices in the population synthesis that make sense to change.

For example, the default kick option is still the Hobbs (2005) kick. We should adapt this based on those works.

Additionally, there are other sources of updated information. For example, Sana et al. (2025) shows a preference for a flatter initial period distribution than that suggested by Sana et al. (2012), which impacts the formed populations.